Grid-Connected Energy Storage Systems: State-of-the-Art and Emerging Technologies

G id-Connec ed Ene gy S o age Sys ems: S a e-o - he-A and Eme ging Technologies This a icle discusses p os and cons o a ailable ene gy s o age, desc ibes applica ions whe e ene gy s o age sys ems a e needed and he g id se ices hey can p o ide, and demons a es di e en powe elec onic solu ions. By GLEN G. FARIVAR ,Senio Membe IEEE,WILLIAM MANALASTAS,JR., HOSSEIN DEHGHANI TAFTI ,Senio Membe IEEE,SALVADOR CEBALLOS , ALAIN SANCHEZ-RUIZ ,Senio Membe IEEE,EMMA C. LOVELL, GEORGIOS KONSTANTINOU ,Senio Membe IEEE, CHRISTOPHER D. TOWNSEND ,Membe IEEE,MADHAVI SRINIVASAN, AND JOSEP POU ,Fellow IEEE ABSTRACT |High pene a ion o enewable ene gy esou ces in he powe sys em esul s in a ious new challenges o powe sys em ope a o s. One o he p omising solu ions o sus ain he quali y and eliabili y o he powe sys em is he in eg a ion o ene gy s o age sys ems (ESSs). This a icle in es iga es he cu en and eme ging ends and echnologies Manusc ip ecei ed 1 No embe 2021; e ised 5 Ma ch 2022; accep ed 3 June 2022. Da e o publica ion 28 June 2022; da e o cu en e sion 5 Ap il 2023. This wo k was suppo ed in pa by he O ice o Na al Resea ch Global unde G an N62909-19-1-2081, in pa by he Na ional Resea ch Founda ion o Singapo e In es iga o ship unde Awa d NRFI2017-08, and in pa by he I2001E0069 Indus ial Alignmen Funding. (Co esponding au ho : Josep Pou.) Glen G. Fa i a is wi h he Ene gy Resea ch Ins i u e, Nanyang Technological Uni e si y, Singapo e 639798 (e-mail: [email p o ec ed].sg). William Manalas as,J ., and Madha i S ini asan a e wi h he School o Ma e ials Science and Enginee ing, Nanyang Technological Uni e si y, Singapo e 639798 (e-mail: wmanalas [email p o ec ed].sg; madha i@n u.edu.sg). Hossein Dehghani Ta i and Ch is ophe D. Townsend a e wi h he Depa men o Elec ical, Elec onic, and Compu e Enginee ing, The Uni e si y o Wes e n Aus alia, C awley, WA 6009, Aus alia (e-mail: [email protected] u.edu.sg; [email protected] g). Sal ado Ceballos is wi h Tecnalia, Basque Resea ch and Technology Alliance (BRTA), 48160 De io, Spain (e-mail: sal ado .ceballos@ ecnalia.com). Alain Sanchez-Ruiz is wi h Inge eam R&D Eu ope, 48170 Zamudio, Spain, and also wi h he Depa men o Elec onic Technology, Uni e si y o he Basque Coun y (UPV/EHU), 01006 Vi o ia-Gas eiz, Spain (e-mail: alain.sanchez@ ehu.eus). Emma C. Lo ell is wi h he School o Chemical Enginee ing, Uni e si y o New Sou h Wales, Sydney, NSW 2052, Aus alia (e-mail: e.lo [email protected]). Geo gios Kons an inou is wi h he School o Elec ical Enginee ing and Telecommunica ions, Uni e si y o New Sou h Wales, Sydney, NSW 2052, Aus alia (e-mail: g.kons an [email protected]). Josep Pou is wi h he School o Elec ical and Elec onic Enginee ing, Nanyang Technological Uni e si y, Singapo e 639798 (e-mail: [email protected] g). Digi al Objec Iden i ie 10.1109/JPROC.2022.3183289 o g id-connec ed ESSs. Di e en echnologies o ESSs ca e- go ized as mechanical, elec ical, elec ochemical, chemical, and he mal a e b ie ly explained. Especially, a de ailed e iew o ba e y ESSs (BESSs) is p o ided as hey a e a ac ing much a en ion owing, in pa , o he ongoing elec i ica- ion o anspo a ion. Then, he se ices ha g id-connec ed ESSs p o ide o he g id a e discussed. G id connec ion o he BESSs equi es powe elec onic con e e s. The e o e, a su ey o popula powe con e e opologies, including ans o me -based, ans o me less wi h dis ibu ed o com- mon dc-link, and hyb id sys ems, along wi h some discussions o implemen ing ad anced g id suppo unc ionali ies in he BESS con ol, is p esen ed. Fu he mo e, he equi emen s o new s anda ds and g id codes o g id-connec ed BESSs a e e iewed o se e al coun ies a ound he globe. Finally, eme ging echnologies, including lexible powe con ol o pho- o ol aic sys ems, hyd ogen, and second-li e ba e ies om elec ic ehicles, a e discussed in his a icle. KEYWORDS |Ba e y ene gy s o age sys em (BESS); ene gy s o age sys em (ESS); g id codes; hyd ogen; powe elec onic con e e ; enewable ene gy. I. INTRODUCTION E e y ene gy s o age sys em (ESS) uns h ough a cycle o cha ge and discha ge wi h a long- e m ene gy balance equi ed be ween cha ge and discha ge o he s able and sus ainable ope a ion o he sys em. Ene gy s o ed in he This wo k is licensed unde a C ea i e Commons A ibu ion 4.0 License. Fo mo e in o ma ion, see h ps://c ea i ecommons.o g/licenses/by/4.0/ Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 397 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies ea h as ossil uels o e he cou se o millions o yea s is no excep ion o his. The issue wi h he cu en a e o u iliza ion is no jus he ine i able deple ion o his aluable esou ce (wi h cu en p oduc ion a es based on 2020 known esou ces, oil and gas a e es ima ed o las 50 and 49 yea s, espec i ely, while coal will un ou a e 139 yea s [1]) bu also i s side e ec o emi ing g eenhouse gases. In ac , conside ing he la e , i is es ima ed ha , by 2050, nea ly 60% o oil and me hane gas and 90% o coal mus emain unex ac ed o ha e a 50% p obabili y o limi ing global wa ming o 1.5 ◦C[2]. Acco dingly, he e is a need o u gen ly modi y he way socie y uses his na u al ESS by d as ically educing he discha ge a e (bu n ewe ossil uels) and inc easing he cha ging a e (plan mo e ees) o es o e he na u al balance. Achie ing his o cou se elies on u ilizing o he ene gy sou ces. Ine i ably, in he nea u u e, almos all o ou ene gy consump ion will be gene a ed om sus ainable sou ces. Cu en ly, wind, sola , and hyd o a e he p edominan enewable sou ces ha ha e eached echnological ma u- i y and wi h he cu en p ojec ion o deploymen a es; p esumably, hey will be he backbone o ou elec ic powe gene a ion o he o eseeable u u e [3]. O cou se, any b eak h ough in p omising dis up i e ech- nologies, such as nuclea usion eac o s, can al e his p esump ion [4]–[6]. Elec ic powe g ids ope a e on a delica ely main ained balance be ween gene a ion and consump ion. Con en- ionally, gene a ion was lexible o ollow he load demand. Howe e , gi en he in e mi en and uncon olled na u e o enewable powe gene a ion, powe g ids will ha e o inc easingly ely on ESSs o p ese e balanced ope a ion. This is why, as seen in Fig. 1, in line wi h an inc easing amoun o in e mi en wind and sola gene a ion capac- i y [1], ins alled ESS capaci y has o inc ease as well [7]. ESSs’ ole as an enable o ha ing a sus ainable g id based on enewables is demons a ed based on Aus alia’s expe ience in [8]. Ha ing o in es in o en-expensi e ESSs is indeed an undesi able consequence o eplacing dispa chable con- en ional powe plan s wi h in e mi en wind and sola plan s. Howe e , he e a e p omising eme ging echnolo- gies ha add lexibili y o bo h gene a o s and loads o e ec i ely educe eliance on ESSs [9], [10]. Such lexible asse s essen ially y o educe he misma ch be ween gene a ion and consump ion and, as a esul , educe ESS cha ge and discha ge. This a icle aims o p o ide an o e iew o g id- connec ed ESS echnologies and he ole hey play in enabling elec ici y powe g ids o he u u e when dom- ina ed by in e mi en enewable sou ces. Special a en- ion is gi en o elec ochemical ESS echnologies ha a e also used in elec ic ehicles (EVs), and as a esul , hey a e expe iencing apid g ow h and de elopmen ac i i ies, which is e iden om an e e -inc easing yea ly ins alled capaci y, as shown in Fig. 2 [11]. Powe elec- Fig. 1. (a) Wind and sola gene a ion capaci y (da a sou ced om [1]). (b) Cumula i e ESS powe capaci y (da a sou ced om [7]). (c) Wo ldwide dis ibu ion o he agg ega e ope a ional ESS powe capaci y (da a sou ced om [7]). onics con e e s a e he enable s o g id in eg a ion o such ESS echnologies. A comp ehensi e e iew o powe con e e s o g id and EV applica ions is p o ided in [12] and [13]. Compa ed o hese e e ences, his a icle expands he e iew by including he ollowing echnology ad ancemen s: 1) con ol and eme ging egula ions o g id suppo unc ionali ies; 2) ad ancemen s in solid-s a e- ans o me (SST) echnology; 398 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Fig. 2. Yea ly ins alled ba e y ene gy s o age capaci y (da a sou ced om [11]). 3) powe dispa i y limi s and s able ope a ing ange o modula powe con e e s. The o ganiza ion o his a icle is gi en as ollows. Fo he sake o comple eness, in Sec ion II, p ominen ESS echnologies a e e iewed. Sec ion III is de o ed o u he expanding he e iew on selec ed ESS echnolo- gies ha a e empowe ing he elec i ica ion o anspo a- ion. In Sec ion IV, he signi icance and ole o ESS in mode n elec ic powe g ids a e es ablished. Powe elec- onic in e ace opologies o g id connec ion o ba e y ESSs (BESSs) and g id codes and s anda ds ela ed o g id connec ion o in e e s a e e iewed in Sec ion V. Sec ion VI looks a ad ancemen s in con olling BESSs o enable addi ional g id suppo unc ionali ies. Sec ion VII discusses some upwa d ending ela ed echnologies and p ospec s. Finally, some concluding ema ks a e p o ided in Sec ion VIII. II. ENERGY STORAGE TECHNOLOGIES A comp ehensi e e iew o a ailable ene gy s o age ech- nologies is epo ed in [14]–[17]. Fig. 3 shows an o e iew o he ene gy s o age echnologies [18] and hei sha e o cu en ope a ional ESS capaci y based on he da a om he U.S. Depa men o Ene gy, Global Ene gy S o age Da abase [7]. Some ea u es o each ca ego y a e discussed in he ollowing. Mechanical: In his ca ego y, pumped hyd o s o age (PHS) is one o he oldes , mos popula , and mos ma u e o ms o s o ing ene gy da ing back o he 1920s and cu en ly accoun s o o e 90% o g id ene gy s o age capaci y [19]. Pumped s o age is no mally associa ed wi h es ablished hyd oelec ic dams on i e s, whe e wa e is pumped back o an ele a ed s o age dam. Howe e , i is also possible o use la ge unde g ound ca e ns o PHS pu poses [20]. Such geological ca e ns o old mines a e sui able o use in comp essed ai ene gy s o age (CAES) as well [21]. CAES ope a es on a simila p inciple o PHS, i.e., d i ing a u bine h ough s o ed po en ial ene gy. The mal: A no able example o he mal s o age o p oducing elec ici y is he concen a ed sola powe plan (CSP). CSP ope a es in a simila way o a con en ional s eam u bine powe plan ; howe e , he hea sou ce is o en mol en sal p oduced by concen a ing sola adia- ion [22]. Elec ical: Supe capaci o s and supe conduc ing mag- ne ic ene gy s o age a e he wo p ominen elec ical ene gy s o age echnologies. Bo h ea u e low ene gy den- si y and high powe densi y. While he o me has ound many applica ions equi ing as and equen cha ge and discha ge [23], he cos -e ec i eness o he la e in p ac- ice is s ill deba able as i equi es main aining ex emely low empe a u es [24]. Elec ochemical: Ba e ies a e one o he mos di e se and apidly g owing o ms o ene gy s o age echnology. Thei signi icance is no jus ele an o g id-connec ed sys ems bu also o he au omo i e indus y [25]. Mo e dis- cussion abou his echnology is p o ided in Sec ions III, V, and VI. Chemical: Chemical s o age compa ed o he p e iously discussed echnologies is unique in he sense ha i can be anspo ed and, owing o i s high-ene gy capaci y, can p o ide a seasonal ene gy s o age op ion o he powe Fig. 3. (a) Ca ego y o ESS echnologies (de ails a ailable in [18]). (b) S o age capaci y dis ibu ion among he ESS echnologies (da a sou ced om [7]). Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 399 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Table 1 Key Pe o mance Indica o s o ESS Technologies (Da a Sou ced F om [18]) g id [26]. In pa icula , hyd ogen is eme ging as a a ge in chemical ene gy s o age echnology. The e e se p ocess o gene a ing elec ici y occu s ei he indi ec ly h ough con en ional gas u bine powe plan s o di ec ly h ough uel cells [27]. Gi en he signi icance o his echnology o eaching 100% ene gy sus ainabili y, i is comp ehensi ely e iewed in Sec ion VII-C. In o de o compa e he main ea u es o some selec ed ESS echnologies, Table 1 summa izes hei key pe o - mance indica o s. F om he p o ided da a, i is no ha d o see why PHS is he dominan and p e e ed ESS op ion. Howe e , i can only be applied whe e a sui able geo- g aphical se ing is a ailable nea by. Some examples o he ecen ESS deploymen p ojec s a e p o ided in he Appendix. Among he ESS echnologies, capaci o s, ba e ies, and uel cells a e closely ela ed as hey di ec ly p oduce a dc ol age (wi hou he need o any elec omechanical gene a o ), and in addi ion, o powe g id applica ions, hey a e applied o powe EVs. A mo e comp ehensi e e iew o hese echnologies is p o ided in Sec ion III. III. ELECTROCHEMICAL ENERGY STORAGE Elec ochemical powe packs ha e os e ed human com- o s o po able connec i i y, mechanical au oma ion, and an elec i ied li ing en i onmen . Such de ices a e capable o ul ahigh e iciencies. They do no su e om he 51% Ca no e iciency h esholds o combus ion engines. They can be used in a e sa ile ange o o m ac o s, anging om hin ilms o ca idges o block modules. They sim- pli y echa ging logis ics by aking ad an age o a la ge p eexis ing powe g id a chi ec u e. In addi ion, hey can be eadily in eg a ed as pe elec ic a ing equi emen s ia cell s acking. The echnological p inciple is ul ima ely based on he Ne ns equa ion: ΔG=nF E. He e, he eleased chemical ene gy (ΔG)is he p oduc o he di ec ed mig a ion o elec ical cha ge (n), Fa aday’s cons an (F),and heelec- ochemical po en ial (E)be ween wo subs ance masses. The genius o he ea ly elec ochemis s was he ealiza ion ha elec on anspo and ion anspo occu ing in mundane combus ion, o ins ance, could heo e ically be decoupled, hus e ec i ely d i ing elec omagne ic mo o s. No only ha , by limi ing he anspo o ei he elec ons o ions, one could e ec i ely swi ch OFF he elease o s o ed ene gy. This has, hus, c ea ed a b idge be ween space and ime o supplying elec ic ene gy when and whe e i is needed a e y low penal ies o en opic ene gy loss. This is in s a k con as o mechanical engines based on p essu e– empe a u e di e en ials, whe ein gas exhaus s s ill ca y subs an ial unha nessed ene gy. The e minological ca ego y o elec ochemical powe packs is elec ochemical-ene gy s o age (EES) de ices. They exploi he chemical po en ial di e ences exis ing be ween seg ega ed ac i e ma e ials, which ep esen s s o ed ene gy. Ac i e ma e ials when b ough oge he in di ec in ima e con ac may esul in an explosi e bu s o hea ene gy om elec on-ion di usion in e mixing. Wha EES de ices do is decouple he ion anspo using an in e nal elec oly e, om he elec on anspo , which is edi ec ed h ough an ex e nal load o pe o m use ul wo k. EES de ices can be classi ied in o uel cells, ba e ies, and capaci o s, as shown in Fig. 4. Rema k: In his sec ion and he ea e in his a icle, o ease o e e ence and o unde sco e he close associa ion o hese echnologies, he de ini ion o EES is expanded o include capaci o s (elec ical) and uel cells (chemical) ESS echnologies. A. Fuel Cells Fuel cells oxidize “ uels” (e.g., H2, ace ylene, me hanol, e hanol, NH3,H 2O2, and na u al gas) using p ecious-me al ca alys s, and hei o al ene gy ou pu is only limi ed by how much uel can be supplied [28]–[30]. This uel de i es mos ly om he pe ochemical indus y, pho ochemical ca alys s (∼17% gene a ion e iciency), o dual-elec ode elec olysis/ he mal ca alysis (65%–85% gene a ion e i- ciency). Gene a ed uels pose logis ical challenges, and in pa icula , H2, al hough ligh weigh , pe mea es h ough s ainless s eel and mos plas ic piping, and is explosi e (mo e discussions a e p o ided in Sec ion VIII). Fuel cells ypically ope a e be ween 20 ◦C and 1100 ◦C depending 400 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Fig. 4. Gene al diag am o EES wo king p inciples: ba e ies, capaci o s, and uel cells. Ba e ies depend on shu le-like chemical edox eac ions. Capaci o s a e based on ield-induced cha ge sepa a ion. Fuel cells p o ide powe by oxidizing ex e nal uels h ough hei ca alys elec odes. on he memb ane echnology, whe e ele a ed empe a- u es a e usually equi ed o achie e accep able cu en a es h ough he elec oly e despi e lowe powe e i- ciencies (due o he need o hea ing) [31], [32]. The li e ime o a uel-cell s ack can u he be se iously lim- i ed by poisoning/coking/phase seg ega ion issues o he ca alys co e in an uncon olled se ing. P ope ly se up, howe e , uel cells a e ex emely aluable o ene gy- o acious ins alla ions equi ing unin e up ed powe sup- ply o p olonged pe iods wi h i ually ze o in e mi en down ime. The la ges comme cial supplie s o hea y- du y s acks as o he yea 2020 include Bloom Ene gy, Kyoce a, SOLIDpowe , and FuelCell Ene gy wi h uni demons a ions exhibi ing 45%–75% elec ical e icien- cies and cell s ack deg ada ion a es o 0.4%–0.9% pe 1000 h (3.5%–7.9% pe yea ) [33]. Ce es Powe s ands ou o compac , modula uni s (5 kW) equi ing minimal high- empe a u e insula ion, exhibi ing <0.2% deg ada- ion/1000 h (∼1.7% pe yea ), gua an eeing a sa is ac- o y se ice li e ime o a leas en yea s, ope a ing a ∼0.9 V/cell and >250 mA/cm2nea 600 ◦C [34]–[37], which is a ea echoed by as - ising p oduce s in China as well [38]. On he lab scale, nanoenginee ed ca hodes ha e been able o sus ainably achie e 20x he ma ke cu en a es (4.7 A/cm2a 0.7 V, 650 ◦C), a mos p omising ea o mo e e ec i e u iliza ion o p ecious me al ca a- lys s [39]. B. Ba e ies Whe eas uel cells ely on an ex e nal ma e ial exchange, ba e ies ope a e on a ixed-dimension he me ic o ma , which s o es in e nally all he ac i e ma e ials. The de ice allows o bo h consump ion and egene a ion o he “ uel” in an encapsula ed de ice, simply by using ex e - nal connec o s wi h applied ol age/cu en limi s. He ein, he ac i e ma e ials a e o en in a solid o liquid phase, which acili a es ma e ial compa men aliza ion, bu his is no pe ec . A key poin is ha he oxida ion s a es in he elec odes a y h ough cycling, and compensa o y mass ans e mus occu o p e en a esis i e pola iza ion buildup. Hys e esis in he mass ans e is o en he cul- p i o ba e y deg ada ion. Fu he mo e, ba e ies mus ine i ably go h ough a cha ging s ep when all he s o ed ene gy is spen , unlike uel cells. Ba e y chemis ies a e widely di e se and can make use o mos elemen s ac oss he pe iodic able [40], [41]. O hese, ad anced li hium-ion ba e ies lead wi h 304-Wh/kg (700-Wh/L) speci ic ene gies based on s a e-o - he-a NMC/Si-C cells, which a e qui e close o he pe o mance guidelines se by he U.S. Ad anced Ba e y Conso ium (350 Wh/kg and 750 Wh/L) and also he physicochemical limi s (400 Wh/kg and 800 Wh/L) o Li-ion ba e y echnology [42]–[44]. Ba e y- ela ed behemo hs oday include he Ame ican Tesla, he Chinese CATL/BYD/SVOLT/Guoxuan High- Tech, he Ko ean Samsung SDI/LG Chem/SK Inno a ion, he Japanese Panasonic, he Swedish No h ol , and a conso ium o o he eme ging Eu opean playe s, who ha e commi ed in es men s on NCA (o NMC o LFP)/liquid elec oly e/g aphi e (o Si) cell echnologies mos ly. O he han hese, he now-de unc Aquion is specialized in a o dable g id-deployed aqueous-elec oly e sodium ba e ies bu was e en ually o e aken by Li-ion ba e y ad ances h ough economies-o -scale p icing and shee policy suppo . Mo ing away om Na-S, Ni-Cd, lead-acid, and edox- low ba e ies [45], he de eloping ends ocus on de eloping Co- ee elec odes h ough luo ina ion, o ganically de i ed elec odes, Li- ich composi ions, liquid-elec oly e Li-me al ba e ies, solid-elec oly e Li-me al ba e ies, anionic shu le ba e ies, and mul i alen -ion aqueous ba e ies, he bes o which p omises g ea e han 500-Wh/kg and 1000-Wh/L s o age me ics [42]. Doping and g ain mo phology con ols a e common hema ic s a egies o imp o ing ma e ial pe o mances, o ins ance, in he case o LiCoO2 ma e ials, which, al hough possessing a heo e ical capaci y o 274 mAh/g, adi ionally, a ained only 165 mAh/g in comme cial samples due o signi ican s uc u al ins abili y when cha ging abo e 4.35 V ( e sus Li+) bu o which 190-mAh/g le els ha e, inally, been unlocked ia Al/La doping s abiliza ion o enable cha ging un il 4.50 V ( e sus Li+) [46]. Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 401 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies C. Capaci o s Capaci o s ope a e simila o ba e ies, excep o he absence o edox eac ions. He e, ene gy is s o ed as concen a ed elec on/ion cha ge on opposi e elec odes o a dielec ic medium. Because capaci o s ely on su ace s o age, hei elaxa ion ime is e y as , and hei powe densi yisconsequen ly e yhigh.Howe e , heyloseou on ene gy densi y o ba e ies, which can u ilize bo h he su ace ma e ial and he subsu ace bulk. Recen ends in 2-D-ma e ial ac i e ma e ials (one-a om- hick shee s o ew-laye shee s) blu he ba ie be ween ba e ies and capaci o s (supe capaci o s, ul acapaci o s, and hyb id capaci o s), achie ing a a o able balance o speci ic ene gy and speci ic powe pe o mances [47], [48]. How- e e , one mus be lucid in in e p e ing claims in epo ed s o ed ene gies, as e y ligh , lu y, and poo ly packing ma e ials may ac ually necessi a e a highe amoun o hea y casing ma e ial [49]. None heless, capaci o s a e c i ical o bu e ing ene gy s o age/ elease e en s on ul a as imescales (<1 min) and possess excep ionally e y high ope a ion li e imes (>10 yea s), as ac i ely exempli ied in Eu opean ams and Chinese sho -dis ance buses. D. Gene al Pe spec i e The chie conside a ion in choosing uel cells, ba e - ies, o capaci o s o g id s o age elies p ima ily on one conside a ion: cos pe kWh. Ma e ial mining, p ocessing, p oduc ion, shipping, handling, and assembly all ep e- sen hea y economic o e heads, whe ein >60% o he de ice cos de i es om he physical ma e ial compo- nen s [50], [51]. Needing only a ew g ams (li e s) ins ead o a ew kilog ams (gallons) o ma e ial ep esen s sig- ni ican supply-chain sa ings. The e o e, he e is always an ad an age o e icien ma e ial usage e en hough he o al weigh and space oo p in s a e nonissues wi h g id EES as hey a e immobile modula ins alla ions and can be buil e ically in limi ed pa ches o land. Fu he mo e, echnology-choice pa ame e s o highe ene gy densi y, highe powe densi y, be e ound ip e iciencies, longe calenda li e imes, ope a ional sa e y, en i onmen al ben- e i s, and ecyclabili y in a closed-loop economy ha e hid- den cos sa ings no mally unaccoun ed o in appa en cos calcula ions. These echnical pa ame e s a e summa ized in Fig. 5 and Table 2 [52], [53]. On an addi ional no e, wi h bu geoning popula ion g ow h and ene gy needs h oughou he globe, he e is no sho age o a pe ennial economic d i e o imp o ed EES echnologies. Coupled wi h economies-o -scale, he c i ical p ice poin o massi e adop ion o EES echnologies is expec ed o be a he 100 $/kWh poin o ba e ies (op i- mis ically se ing wi hin his decade, 2020–2030), which is s ill much mo e expensi e han he 16 $/kWh p omised by uel cells (assuming a en-yea s ack li e ime). This added p ice p emium o ba e ies o e uel cells is s ill ole able Fig. 5. (a) Typical ol age p o iles o EES de ices wi h espec o ime (gal anos a ic condi ions: when holding elec ic cu en cons an ). (b) Ragone plo o a ious EES echnologies (adap ed om [32] and [42]–[44]). gi en he logis ical ad an ages and educed eliance on p ecious me als [54]–[56]. IV. POWER GRID ENERGY STORAGE REQUIREMENTS ESSs add lexibili y o he en i e powe g id by being able o unc ion as he gene a ion, consump ion, and/o eac i e powe compensa ion asse s. They deli e a wide ange o se ices ha co e all he segmen s o he ene gy alue s eam anging om con en ional and enewable gene a ion, ansmission, and dis ibu ion up o he inal cus ome [16], [57]–[59]. Fig. 6 shows a classi ica ion o he main ene gy s o - age applica ions and how hey a e dis ibu ed pe seg- men [57], [58]. Each applica ion is b ie ly discussed in he ollowing, and some p ac ical examples a e gi en in he Appendix. A. Con en ional/Bulk Gene a ion Se ices ESSs p o ide se ices ha con ibu e o op imize he ope a ion o con en ional synch onous gene a ion in e ms o lexibili y, e iciency, and economic e u n. The main ESS se ices associa ed wi h con en ional gene a ion a e gi en as ollows. 402 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Table 2 Key Ad an ages/Disad an ages o Va ious ESS Technologies Ene gy A bi age: The p ac ice o using ESSs o s o e he ene gy when he p ice is low and o sell i a peak imes when he p ice is high. I con ibu es o op imize economically he use o gene a ion asse s [60]–[62]. Peak Sha ing: The p ac ice o using ESSs o s o e ene gy when he demand is low and discha ge i o emo e he peaks o he load. The p inciple o peak sha ing is simila o ha o ene gy a bi age, bu peak sha ing does no ollow any economic a ge [63], [64]. Load Le eling: Load le eling makes use o ESSs o s o e ene gy when he demand is low and o injec i back in o he g id when he elec ical load is high. The main di e ence be ween load le eling and peak sha ing elies on ha he o me ocuses on la ening he load a he han jus emo ing he peaks [65], [66]. Gene a o B idging: I is he p ac ice o using ESSs o supply he load while ansi ioning be ween gene a- o s [57], [58], [67]. Gene a o Ramping and Load Following: Usually, ESSs o e mo e apid esponse imes o load changes com- pa ed o gene a o uni s. This se ice makes use o ESSs o p o ide suppo in ollowing load changes and ake o e as load a ia ions allowing he gene a o s o amp up/down hei powe acco ding o hei echnical ecom- menda ions. I con ibu es o enhance he li e cycle o he gene a o s and he powe quali y [68], [69]. Black-S a : I is he p ac ice o using ESSs o es o e a pa o he powe g id a e a black ou . When e e ing o isola ed g ids, i is he p ac ice o ene gizing he g id p o iding he equi ed powe and ol age be o e he gen- e a ing uni s come in o ope a ion [70]–[72]. B. Renewable Gene a ion Se ices ESSs a e equi ed o p o ide he powe g id wi h he equi ed lexibili y o cope wi h he inhe en a iabili y o enewable ene gy sys ems. They con ibu e o balancing a iable gene a ion wi h he load, hus dec easing he need o dispa chable synch onous gene a ion capaci y and he a es o powe cu ailmen . The main ESS se ices associ- a ed wi h enewable ene gy sys ems a e gi en as ollows. Cu ailmen Minimiza ion: The p ac ice o using ESSs o abso b he ene gy ha canno be injec ed in o he g id Fig. 6. ESS applica ions. Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 403 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies du ing pe iods o ime wi h excess enewable gene a ion, due o he a ailabili y o p ima y esou ces, and low demand. S o age ene gy is deli e ed o he g id when needed [73], [74]. Capaci y Fi ming: The p ac ice o using ESSs o smoo h he powe injec ed in o he elec ical g id by enewable ene gy sys ems du ing a gi en pe iod. This se ice makes use o ESSs o s o e ene gy du ing hou s o peak p oduc- ion ega dless o he load. The s o ed ene gy is injec ed back in o he g id o supplemen he a iable ene gy gen- e a ion when he gene a ion dec eases. Capaci y i ming is also used o smoo h sho - ime ene gy luc ua ions due o as changes in he p ima y esou ce [75], [76]. Ancilla y Se ices Suppo : The use o ESSs o help a iable enewable gene a ion sys ems o con ibu e o he p o ision o ancilla y se ices by keeping an ex a ene gy ese e. In his way, enewable gene a ion sys ems combined wi h ESSs can con ibu e o he p o ision o new ancilla y se ices, such as ine ia emula ion, as equency esponse, p ima y equency con ol, o dynamic eac i e con ol, among o he s [77]–[79]. C. T ansmission Se ices ESSs a e capable o pe o ming as ansmission asse s as well. The main se ices ha ESSs p o ide o he ansmis- sion sys em a e gi en as ollows. P ima y/Seconda y/Te ia y F equency Con ol: ESSs can con ibu e o co ec equency de ia ions by means o [80]–[82] he ollowing: 1) main aining a balance be ween gene a ion and demand wi hin a synch onous a ea a e a dis u - bance (p ima y equency con ol); 2) adjus ing he ac i e powe gene a ion o es o e he nominal equency ollowing a dis u bance (sec- onda y con ol); 3) es o ing he p ima y and seconda y equency con- ol ese es ( e ia y con ol). Angula S abili y: I e e s o he p ac ice o using ESSs o con ibu e o he educ ion o load-angle a ia ions ollowing a dis u bance by means o p ocessing high powe le els in sho pe iods. This con ibu es o imp o e he angula s abili y o he g id [82], [83]. Vol age Suppo : ESSs can also be used as dis ibu ed eac i e powe sou ces o sinks, hus con ibu ing o eg- ula e ol age le els h ough he nodes o he ansmission and dis ibu ion ne wo ks [82], [83]. T ansmission In es men De e al: I e e s o he use o ESSs o sol e conges ion issues wi hin he ansmission g id, he eby de e ing he need o implemen ansmission sys em upg ades [84], [85]. T ansmission Suppo : I e e s o he abili y o ESSs o imp o e he ope a ion o he ansmission sys em du ing dis u bances, such as ol age sags, local and in e a ea sub- synch onous oscilla ions, o ol age ins abili ies, among o he s [86], [87]. D. Dis ibu ion Se ices The dis ibu ion g id also bene i s om he use o ESSs mainly due o he ollowing se ices. Capaci y Suppo and In es men De e al: Capaci y sup- po e e s o he p ac ice o using ESSs o shi load om peak o base pe iod, hus con ibu ing o inc ease he u iliza ion ac o o in as uc u e and educe he con- ges ion h ough he dis ibu ion ne wo k. Consequen ly, he need o implemen dis ibu ion g id upg ades is de e ed [84], [85]. Con ingency G id Suppo : I e e s o he p ac ice o using ESSs o ake o e pa o he elec ici y gene a ion, hus edis ibu ing he ene gy luxes, ollowing he loss o a majo componen o he g id. I con ibu es o educe he impac o he loss o a componen in he dis ibu ion g id [88], [89]. Vol age Con ol: The p ac ice o using ESSs o egula e he ol age p o ile wi hin admissible limi s h ough he dis ibu ion ne wo k, hus imp o ing he quali y o supply. Due o he na u e o dis ibu ion g ids, he ol age p o ile can be egula ed by con olling bo h he eac i e and ac i e powe injec ions [90], [91]. Reac i e Powe Compensa ion: I e e s o he use o ESSs o con ibu e o he eac i e powe balance o he g id [92]. E. Cus ome Se ices ESSs a e also used in ene gy managemen applica ions mainly in ended o imp o e he quali y and eliabili y o he powe supplied o he cus ome and educe cus ome cos s. The main cus ome se ices ha ESSs p o ide a e gi en as ollows. End-Use Peak Sha ing: I e e s o he p ac ice o using ESSs by cus ome s o smoo h hei own peak demand, hus con ibu ing o educe he pa o he cos ha is ixed acco ding o he highes powe demand [93]. Time-o -Use Ene gy Cos Managemen :Thep ac iceo using ESSs o educe he elec ici y bill by s o ing ene gy when elec ici y a es a e low and discha ging i a peak imes [94]. Powe Quali y: Fluc ua ions o he gene a ed powe , mainly a ibu ed o he a iabili y o enewable p i- ma y esou ces, cause powe quali y issues mainly lead- ing o ol age a ia ions and ha monics. ESSs can be used o a enua e hese powe luc ua ions, hus con ibu ing o imp o e powe quali y and mi iga e dis u bances o cus ome loads [95]. Con inui y o Ene gy Supply (Ene gy Backup): I e e s o he use o ESSs o eplace he unc ion o he elec ici y ne wo k a e an in e up ion, he e o e p e en ing c i ical loads om being a ec ed by blackou s [96], [97]. Reac i e Powe Compensa ion: I e e s o he capaci y o ESSs connec ed o he g id by means o powe elec onics o p o ide eac i e powe o compensa e o cus ome loads, hus con ibu ing o imp o e e iciency and egula e ol age le els [98]. 404 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Table 3 ESS Cha ac e is ics o P o ide Di e en Se ices o he G id Table 3 shows he main cha ac e is ics o he ESSs o supply hese se ices [16], [59]. The alues indica ed in he able should be unde s ood as app oxima e since hey depend on he speci ic cha ac e is ics o he applica ions. Since he ocus o his a icle is on elec ochemical ESSs, he sui abili y o ba e ies o p o ide hese se ices is indica ed. Fo long- e m se ices o which ba e ies a e no o en u ilized, i is equi ed o use o he ene gy s o age echnologies, such as mechanical, elec ical, he mal, o chemical. V. POWER ELECTRONICS FOR BESS GRID INTEGRATION As discussed in Sec ion III, he EES echnologies di ec ly p oduce dc ol age. Powe elec onic con e e s a e hen used o in e acing his low dc ol age wi h he high ac ol age o he powe g id. In his sec ion, some o he popula con e e echnologies, as shown in Fig. 7, a e discussed. A. Low-F equency T ans o me -Based In e ace The con en ional app oach o g id in eg a ion o BESS is shown in Fig. 8 [12], [13], [99]. He e, he ba e y uni is composed o ba e y cells, modules, and packs. A se ies and pa allel combina ion o cells makes up a module, and a se ies and pa allel combina ion o modules makes up a pack. In his app oach, he ba e y is ea ed as one agg ega ed uni . Howe e , such se ies and pa allel connec ion o many ba e y subuni s is he oo cause o many p oblems in BESS applica ions. This is p edomi- nan ly due o he powe o each se ies s ing being limi ed by he weakes subuni in he s ing [100]. The e o e, Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 405 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Fig. 20. P inciple o FPPT in PV sys ems and i s equali y o ene gy s o age sys ems. 3) he equi ed le el o echnical s udies and modeling equi ed o each new ins alla ion; and 4) upda ed o new g id connec ion s anda ds a e wai ing o be add essed. VII. EMERGING TECHNOLOGIES AND PROSPECTS A. Powe Rese e and Flexible Powe Con ol o PV Sys ems Ins alla ion o PV sys ems is g owing apidly wo ldwide because o go e nmen suppo , high elec ici y cos s, imp o ing echnology, and a dec ease in he PV panel cos . To sus ain powe g id eliabili y and powe quali y in powe g ids wi h high pene a ion o PV sys ems, lexible powe poin acking (FPPT) algo i hms a e implemen ed in hese sys ems [9], [149]. P inciples o FPPT ope a ion in PV a e illus a ed in Fig. 20. Unde his ope a ion mode, he PV powe is egula ed in such a way ha a p ede ined amoun o powe ese e p es is kep in he PV sys em du ing he s eady-s a e ope a ion. This amoun o powe ese e can be u ilized o suppo he g id unde equency o ol age dis u bances. Fo example, i he g id equency dec eases, he PV ou pu powe can inc ease om p pp o pmpp. Following he discussions in Sec ion VII, his ope a ion mode is simila o he beha io o BESSs. Acco dingly, his powe ese e in PV sys ems ope a es simila o a ba e y. The dec eased cos o PV panels and low main enance equi emen s o PV sys ems make hem p omising al e na i es o BESSs in suppo ing he g id. Such unc ionali ies o PV sys ems a e demons a ed in [150]–[153]. Powe ese e con ol wi h FPPT ope a ion has also been implemen ed in mic og id applica ions [154], [155]. In s and-alone dc mic og ids wi h a PV sys em, a BESS is con en ionally used o egula ing he dc-link ol - age and dealing wi h he powe misma ch be ween he supply and he demand, causing a con inuous ba e y ope a ion. Con en ionally, he load and he PV maximum powe dic a e he ba e y cu en . Though ope a ing he PV sys em a i s maximum powe poin yields minimum ba e y discha ge cu en , he opposi e is ue o ba e y cha ging cu en . The e o e, educing he ba e y cha ging cu en based on i s SoC and he amoun o a ailable PV su plus powe (which can be ea ed as i ual s o ed ene gy) is an oppo uni y ha is pu sued in [155] o imp o ing he ba e y li e. The simula ion case s udy shows how he FPPT-based con ol elimina es pa ial cycles, educes he ba e y empe a u e luc ua ions, and, hus, ex ends he Li-ion ba e y li e ime by 29.93% and he lead- acid ba e y li e ime by 42.93% compa ed o a con en- ional MPPT-based con ol [155]. B. Elec ic Vehicles: Oppo uni ies and Challenges Elec i ica ion o anspo a ion has some p o ound implica ions on elec ici y powe g id ene gy s o age. Undoub edly, EVs a e helping o as - ack de elopmen and imp o emen s in sha ed ene gy s o age echnologies, such as supe capaci o s, uel cells, and, mos impo an ly, ba e ies. Nowadays, la ge ca manu ac u e s a e unning an in ense campaign o esea ch and de elopmen ac i - i ies o p oduce sa e, longe las ing, cheape , and highe powe and ene gy densi y ba e ies. These echnologies a e o en di ec ly applicable in g id-connec ed BESSs. On he o he hand, EVs a e also compe ing wi h he g id o ba e y supply. Due o he la ge demand o EVs, he downwa d end o he li hium-ion ba e y cos , as shown in Fig. 21, has almos la ened and is now a he isk o e e sing cou se unless he supply o key me als can keep up wi h demand [156]. A la ge, om he pe spec i e o ene gy s o age equi e- men s, EVs p esen oppo uni ies o he powe g id. Fi s , being a con olled load, hey can pa icipa e in demand- side managemen and educe he need o ESSs. E en mo e in e es ingly, wi h e e se powe low mechanisms, EVs can play he ole o ESSs in he powe g id [ ehicle- o-g id echnology (V2G)] [157], [158]. Second, he e is he oppo uni y o build mass g id-connec ed BESSs by eusing cheap second-li e ba e ies om EVs [159], [160]. None heless, in a nea u u e, ecycling echnologies o exhaus ed Li-ion ba e ies should be implemen ed o limi he en i onmen al impac . The es o his subsec ion is de o ed o u he discuss V2G and Li-ion ba e y ecycling echnologies. V2G Technology:Thisisoneo hehea ilydeba ed opics ha a e expec ed o ha e a majo posi i e impac on he ope a ion and s abili y o he u u e g id. Recen Fig. 21. Pe sis en decline o li hium-ion ba e y p ices o e he pas decade (da a sou ced om [156]). 412 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies ad ancemen s and upda ed s a us o his echnology a e p o ided in [161]. Conside ing ha , on a e age, ehicles in he Uni ed S a es, as an example, a e only used 5% o he day, he easibili y and po en ial o implemen ing he V2G sys em a e undeniable [162]. Howe e , so a , i s po en ial emains un apped mainly due o he ollowing hu dles. 1) EV ba e y deg ada ion is a guably he main d aw- back o V2G echnology. EVs’ ba e y pe o mance is a key ac o o conside when hey a e compa ed o con en ional ehicles. In addi ion o he high cos o eplacing wo n-ou ba e ies, educed use sa is ac- ion due o he educ ion in ange and pe o mance o EVs is ano he downside o implemen ing he V2G sys em. This can change in he nea u u e wi h imp o emen s in ba e y quali y. 2) In as uc u e o implemen ing V2G and he associ- a ed cos o i , o now, emain ano he hu dle. V2G equi es bidi ec ional cha ging s a ions and secu e communica ion channels. Due o he associa ed cos s, as o 2021, only a hand ul o EV b ands suppo V2G (Nissan e-NV200, Nissan LEAF, Mi subishi Ou lande PHEV, and Mi subishi Eclipse C oss PHEV [163]). Li-Ion Ba e y Recycling: Roughly, 85% o cu en ba - e y manu ac u ing elies on i gin ma e ials [164]. Wi h he ise o giga ac o ies and elec i ica ion o na ional economies, his p esen s daun ing ma e ial managemen challenges. This is a signi ican p oblem wi h a an alizing economic ewa d and one ha necessi a es di ec pa - ne ships be ween manu ac u e s and ecycling companies. Fo ins ance, a 400-kg ca ba e y wi h a capaci y o 50 kWh con ains oughly 100-kg g aphi e, 32-kg nickel, 11-kg cobal , 10-kg manganese, and 6-kg li hium, apa om aluminum, s eel, and plas ic componen s [165]. The p e alen iew o ba e y e-was e managemen is a ladde -u iliza ion sys em, whe ein expi ed high- pe o mance ba e ies a e e u bished o no -so- demanding second- and hi d-li e applica ions, be o e inally going o he ecycling pipeline o ex ac he key elemen s o making new ba e ies [166], [167]. In his ega d, TES/G een Li-ion (Singapo e), B unp/GEM (China), SMCC Recycling (Sou h Ko ea), Ame ican Ba e y Technology/ReCell Cen e /Re ie /Redwood Ma e ials (USA), Li-cycle (Canada), P imobius (Aus alia), and Recu- pyl/Akkuse /Duesen eld/Sol ay/No h ol /BASF/Veolia/ Enel G oup/S ena Recycling/ReLIB/Reneos/Elemen al Holding/Powe aul /Umico e (Eu ope) a e leade s in he ield [168], [169]. Singapo e, in pa icula , is eyeing i sel as an e-was e ecycling hub using benign hyd ome allu gical p ocesses o achie e his pu pose (SCARCE) [170], [171]. C. Hyd ogen–Me hane–NH3:Beyond he 100% Renewables As ou lined in Fig. 3, chemical ESSs a e a s ong can- dida e o long- e m, and anspo able, ene gy s o age. Fig. 22. Diag am ou lining a g id-connec ed PV-elec olyze - uel-cell sys em [174]. Fo chemical ESS, elec ici y is used o d i e chemical eac ions in o de o p oduce a ange o chemicals, o en e e ed o as Powe - o-X (P2X). “X” can be conside ed as inclusi e o a ange o chemicals, such as hyd ogen, ammo- nia, and syn he ic na u al gas (me hane). The syn hesized chemicals can hen be s o ed and/o anspo ed and hen ei he combus ed o eac ed o elease he ene gy s o ed wi hin he chemical bonds. Depending on he chemical being p oduced (X), he app oaches o elec ici y con- e sion, s o age, dis ibu ion, and ene gy gene a ion a y conside ably. Hyd ogen is apidly eme ging as one o he key ec o s in chemical ESSs. A hyd ogen-based ESS ypically consis s o elec olyze s, hyd ogen s o age, and uel cells (see Fig. 22). The hyd ogen s o ed, hen, can be u ilized as an indus ial eeds ock, con e ed in o o he “X”s, dis ibu ed as an ene gy ec o , o di ec ly con e ed back o elec ici y using uel cells ( e e o Sec ion III-A). The p oduc ion o hyd ogen ia elec olysis equi es a pu i ied wa e sou ce wi h e e se-osmosis (RO)- ea ed seawa e being also conside ed as a pa hway o mi iga e he equi emen s o use o esh wa e , which can be a sca ce esou ce [172]. To da e, he e a e h ee key elec olyze echnologies being conside ed, polyme elec- oly e memb anes (PEMs), alkaline elec olyze s (AEs)m, and solid oxide elec olyze s (SOEs). SOEs ope a e a high empe a u es (500 ◦C–850 ◦C), which esul s in high e iciencies, and no need o expensi e ca alys s; howe e , his high empe a u e hinde s long- e m du abili y [173]. Hence, o da e, PEM and AE app oaches a e he mos com- mon comme cially. Elec olyze -d i en hyd ogen p oduc- ion can be g id-connec ed, connec ed di ec ly o dedica ed enewables (behind he me e /o -g id), o powe ed by cu ailed enewables [174]. The use o hyd ogen as an ESS echnology has he key bene i o being bo h a long- e m and ans- po able/expo able s o age ec o o enewable powe . Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 413 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Table 4 Examples o Deployed ESS Technologies Typically, hyd ogen can be s o ed h ough ou app oaches: 1) comp ession; 2) lique ac ion; 3) ans o ma ion; and 4) solid-s a e s o age [175]. Hyd ogen can also be ed o gas g id up o 15%–20% wi hou any sa e y conce ns (al hough his numbe is subjec o con en ion) [176]. The s o age o hyd ogen ia comp ession o lique ac ion (1, 2) is no wi hou i s di icul ies. Sa e y conce ns, along wi h hyd ogen’s low densi y and di usibili y, esul in signi ican challenges. Emb i lemen , caused by hyd ogen di usion, limi s he use o high-s eng h s eels o hyd o- gen s o age and anspo a ion ia pipeline [177]. The ans o ma ion o hyd ogen (3) co e s i s con e sion o o he ene gy ec o s, such as me hane (syn he ic na u al gas) and ammonia. The p oduc ion o ammonia ( h ough g een hyd ogen ed Habe Bosch, N2+3H2→2NH3), is gaining inc easing in e es as ammonia has a highe olume ic s o age den- si y compa ed o liquid hyd ogen (108 g/L e sus 71 g/L, espec i ely) [178]. Ammonia can hen be s o ed, used as a e ilize , in uel cells o exploi ed as a hyd ogen ec o o anspo . The ene gy inpu s associa ed wi h he con e sion o ammonia and he egene a ion o hyd ogen om ammonia along wi h i s ela i e oxici y p esen some hind ances. The p oduc ion o me hane ( ia he Saba ie Reac ion, CO2+4H2→CH4+2H2O), o en e e ed o as powe - o-gas (P2G), allows excess ene gy o be s o ed and dis ibu ed in he o m o me hane. This allows in e- g a ion wi h he gas g id, u ilizing exis ing in as uc u e, 414 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies howe e , esul s in he dis ibu ed emission o CO2upon use [179]. In Fig. 22, i is impo an o no e he ole o powe elec onic con e e s in enabling his enewable hyd ogen- based ESS. As can be seen, he e a e wo ypes o powe con e e s in his con igu a ion, he dc–ac g id-connec ing one, and he dc–dc s age o op imizing PV powe . Mos o he powe con e e s o g id in eg a ion (discussed in Sec ion V) a e conside ed ma u e and es ablished indus- ial solu ions, whe eas he dc–dc pa o such appli- ca ions is s ill e ol ing [180]. A comp ehensi e e iew o p ominen dc–dc powe con e e opologies is p o- ided in [180]. In sho , a high-powe equi emen o he g een hyd ogen elec olyze applica ions will demand echnology imp o emen o powe elec onic compo- nen s [181], [182]. VIII. CONCLUSION As long as ou bes -laid plan o achie e ene gy sus ain- abili y es s wi h in e mi en enewable gene a ion, ESS echnologies emain an ine i able componen o enable he ansi ion. Though he con en ional well-es ablished PHS echnology is likely o main ain he lion’s sha e o ins alled ESS capaci y o he o eseeable u u e, he use o g id- connec ed BESSs is accele a ing and is expec ed o play a bolde ole in u u e g ids. The p e alen iew in he ba e y ma e ials communi y is ha an a senal o ESS ech- nologies, and no jus one echnology bu a mul ip onged app oach, is iewed as he mos p ac ical app oach o he global sus ainabili y d i e. Each coun y will ha e endemic special condi ions, which may a o one echnol- ogy o e ano he (geog aphy, na u al esou ces, clima e, and so on). Economies o scale will push p ices down, acili a ing wide adop ion. Fu u e ene gy s o age ech- nologies based on ad anced Li-ion, Na-ion, mul i alen - ion (Zn, Al), hyb id supe capaci o s, hyd ogen, uel cells, and edox- low chemis ies a e gaining o e whelming ac- ion as g id ene gy s o age solu ions. BESS echnology, in pa owing o i s applica ion in EVs, is g owing apidly as e idenced by declining p ices, while quali y imp o es, and he o eseeable ubiqui y o dumped EV ba e ies is seeing a massi e d i e in he ise o second-li e ba e y u ili ies o eco e ini ial ba e y ma e ial cos s. Along wi h imp o emen s in ba e y chemis y, powe elec onic con e e s ha a e used o in e acing BESSs o he g id a e expe iencing a majo u n in hei e olu ion hanks o ad ancemen s in bo h high-powe wide bandgap semi- conduc o s and modula powe elec onic a chi ec u es, u he imp o ing he compe i i eness o BESSs. Reaching 100% sus ainabili y will equi e s o ing a massi e amoun o ene gy o ca e o seasonal enewable gene a ion and demand, o which hyd ogen will play a majo ole. Finally, using echnologies ha add lexibili y o a y gene a ion and consump ion o some ex en can be a cos -e ec i e way o educing eliance on ESSs. APPENDIX Table 4 shows some examples o deployed ESSs a ound he globe ca ego ized based on he echnology and se ices ha hey p o ide [183]. The p ojec s a e selec ed o include examples om all ESS echnology ca ego ies and di e se geog aphic loca- ions. Fu he mo e, he in ended pu poses o each ins alla- ion and hei echnology p o ide s a e included in Table 4. REFERENCES [1] S a is ical Re iew o Wo ld Ene gy,BP,London, U.K., 2021. [2] D.Welsby,J.P ice,S.Pye,andP.Ekins, “Unex ac able ossil uels in a 1.5◦Cwo ld,” Na u e, ol. 597, pp. 230–234, 2021. [3] Renewable Powe , IEA, Pa is, F ance, 2020. [4] Wo ld Nuclea Associa ion. Accessed: 2021. [Online]. A ailable: h ps://www.wo ld- nuclea .o g/in o ma ion-lib a y/cu en -and- u u e-gene a ion/nuclea - usion-powe .aspx [5] J. Ongena and Y. Ogawa, “Nuclea usion: S a us epo and u u e p ospec s,” Ene gy Policy, ol. 96, pp. 770–778, Sep. 2016. [6] Nuclea Fusion S a us and P ospec s, Max-Planck-Ins i u e, Ga ching, Ge many, 2019. [7] DOE Global Ene gy S o age Da abase. Accessed: Feb. 27, 2022. [Online]. A ailable: h ps://sandia.go /ess-ssl/gesdb/public/ s a is ics.h ml [8] F. A año-Va gas, Z. Shen, S. Jiang, J. Fle che , and G. Kons an inou, “Challenges and mi iga ion measu es in powe sys ems wi h high sha e o enewables—The Aus alian expe ience,” Ene gies, ol. 15, no. 2, p. 429, Jan. 2022. [9] H. D. Ta i e al., “Ex ended unc ionali ies o pho o ol aic sys ems wi h lexible powe poin acking: Recen ad ances,” IEEE T ans. Powe Elec on., ol. 35, no. 9, pp. 9342–9356, Sep. 2020. [10] M.Wang,Y.He,X.Xu,Z.Dong,andY.Lei, “A e iew o AC and DC elec ic sp ings,” IEEE Access, ol. 9, pp. 14398–14408, 2021. [11] IEA, Pa is, F ance. (2021). Ene gy S o age. Accessed: Feb. 27, 2022. [Online]. A ailable: h ps://www.iea.o g/ epo s/ene gy-s o age [12] G. Wang e al., “A e iew o powe elec onics o g id connec ion o u ili y-scale ba e y ene gy s o age sys ems,” IEEE T ans. Sus ain. Ene gy, ol. 7, no. 4, pp. 1778–1790, Jul. 2016. [13] S. Vazquez, S. M. Lukic, E. Gal an, L. G. F anquelo, and J. M. Ca asco, “Ene gy s o age sys ems o anspo and g id applica ions,” IEEE T ans. Ind. Elec on., ol. 57, no. 12, pp. 3881–3895, Dec. 2010. [14] F.Nadeem,S.S.Hussain,P.K.Tiwa i, A. K. Goswami, and T. S. Us un, “Compa a i e e iew o ene gy s o age sys ems, hei oles, and impac s on u u e powe sys ems,” IEEE Access, ol. 7, pp. 4555–4585, 2019. [15] M.Faisal,M.A.Hannan,P.J.Ke ,A.Hussain, M. B. Manso , and F. Blaabje g, “Re iew o ene gy s o age sys em echnologies in mic og id applica ions: Issues and challenges,” IEEE Access, ol. 6, pp. 35143–35164, 2018. [16] O. Palizban and K. Kauhaniemi, “Ene gy s o age sys ems in mode n g ids—Ma ix o echnologies and applica ions,” J. Ene gy S o age, ol.6, pp. 248–259, May 2016. [17] W.He,M.King,X.Luo,M.Doone ,D.Li,and J. Wang, “Technologies and economics o elec ic ene gy s o ages in powe sys ems: Re iew and pe spec i e,” Ad . Appl. Ene gy, ol.4, pp. 2666–7924, No . 2021. [18] Eu opean Associa ion o S o age o Ene gy. Accessed: Feb. 27, 2022. [Online]. A ailable: h ps://ease-s o age.eu/ene gy-s o age/ echnologies/ [19] Wo ld Nuclea Associa ion. Accessed: Feb. 27, 2022. [Online]. A ailable: h ps://wo ld-nuclea .o g/in o ma ion- lib a y/cu en -and- u u e-gene a ion/elec ici y- and-ene gy-s o age.aspx [20] W. F. Picka d, “The his o y, p esen s a e, and u u e p ospec s o unde g ound pumped hyd o o massi e ene gy s o age,” P oc. IEEE, ol. 100, no. 2, pp. 473–483, Feb. 2012. [21] B. Clea y, A. Du y, A. Oconno , M. Conlon, and V. F henakis, “Assessing he economic bene i s o comp essed ai ene gy s o age o mi iga ing wind cu ailmen ,” IEEE T ans. Sus ain. Ene gy, ol.6, no. 3, pp. 1021–1028, Jul. 2015. [22] L. F. Cabeza, C. Sole, A. Cas ell, E. O o, and A. Gil, “Re iew o sola he mal s o age echniques and associa ed hea ans e echnologies,” P oc. IEEE, ol. 100, no. 2, pp. 525–538, Feb. 2012. [23] A. Be ue a, A. U súa, I. S. Ma ín, A. E ekha i, and P. Sanchis, “Supe capaci o s: Elec ical cha ac e is ics, modeling, applica ions, and u u e ends,” IEEE Access, ol. 7, pp. 50869–50896, 2019. [24] R. Soman e al., “P elimina y in es iga ion on economic aspec s o supe conduc ing magne ic ene gy s o age (SMES) sys ems and high- empe a u e supe conduc ing (HTS) ans o me s,” IEEE T ans. Appl. Supe cond., ol. 28, no. 4, pp. 1–5, Jun. 2018. [25] E. Chemali, M. P eindl, P. Malysz, and A. Emadi, “Elec ochemical and elec os a ic ene gy s o age and managemen sys ems o elec ic d i e ehicles: S a e-o - he-a e iew and u u e ends,” IEEE J. Eme g. Sel. Topics Powe Elec on., ol. 4, no. 3, pp. 1117–1134, Sep. 2016. Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 415 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies [26] A. O. Con e se, “Seasonal ene gy s o age in a enewable ene gy sys em,” P oc. IEEE, ol. 100, no. 2, pp. 401–409, Feb. 2012. [27] M. Fa ooque and H. C. Ma u, “Fuel cells—The clean and e icien powe gene a o s,” P oc. IEEE, ol. 89, no. 12, pp. 1819–1829, 2001. [28] D. R. Dekel, “Re iew o cell pe o mance in anion exchange memb ane uel cells,” J. Powe Sou ces, ol. 375, pp. 158–169, Jan. 2018. [29] M. Ande sson and B. Sund˙en, “Technology e iew—Solid oxide uel cell,” Swedish Elec omobili y Cen e, Go henbu g, Sweden, Tech. Rep. 2017:359, 2017. [30] Manu ac u ing Cos Analysis o 100 and 250 kW Fuel Cell Sys ems o P ima y Powe and Combined Hea and Powe Applica ions, Ba elle Memo ial Ins ., Columbus, OH, USA, 2016. [31] S. K. Su apa ajua, S. K. Na a ajan, and P. Ka hikeyan, “A succinc e iew on uel cells,” in P oc. IOP Con ., Ea h En i on. Sci., 2019, A . no. 012012. [32] E. D. Wachsman and K. T. Lee, “Lowe ing he empe a u e o solid oxide uel cells,” Science, ol. 334, no. 6058, pp. 935–939, No . 2011. [33] M. C. Williams, S. D. Vo a, and G. Jesionowski, “Wo ldwide s a us o solid oxide uel cell echnology,” ECS T ans., ol. 96, no. 1, pp. 1–10, Jan. 2020. [34] A. Balla d e al.,“De elopmen o he5kWe S eelCell echnology pla o m o s a iona y powe and anspo applica ions,” ECS T ans., ol. 91, no. 1, pp. 117–122, Jul. 2019. [35] A. Mahgoub e al., “Li e ime p edic ion o S eelCell? S acks using ad anced mul iphysics modelling,” in P oc.Eu .SOFCSOEFo um, Luce ne, Swi ze land, 2020, pp. 1–10. [36] D. Udomsilp e al., “Me al-suppo ed solid oxide uel cells wi h excep ionally high powe densi y o ange ex ende sys ems,” Cell Rep. Phys. Sci., ol. 1, no. 6, Jun. 2020, A . no. 100072. [37] C. Vesely, P. Ba na d, and B. Dosanjh, “Me al-suppo ed ce ia elec oly e-based SOFC s ack o scalable, low-cos , high-e iciency and obus s a iona y powe sys ems,” Uni ed S a es Dep .Ene gy,Washing on,DC,USA, Tech. Rep., 2021, doi: 10.2172/1772925. [38] M. Hu, “The cu en s a us o hyd ogen and uel cell de elopmen in China,” J. Elec ochemical Ene gy Con e s. S o age, ol. 17, no. 3, Aug. 2020, A . no. 034001. [39] K. De elos-Baga inao, T. Ishiyama, H. Kishimo o, H. Shimada, and K. Yamaji, “Nanoenginee ing o ca hode laye s o solid oxide uel cells o achie e supe io powe densi ies,” Na u e Commun., ol. 12, no. 1, p. 3979, Dec. 2021. [40] P. Vanýsek and V. No ák, “His o ic and supp essed echnologies o ene ge ics,” J. Ene gy S o age, ol. 27, Feb. 2020, A . no. 101105. [41] R. Demi -Cakan, M. R. Palacin, and L. C oguennec, “Recha geable aqueous elec oly e ba e ies: F om uni alen o mul i alen ca ion chemis y,” J. Ma e . Chem. A, ol.7,no.36, pp. 20519–20539, 2019. [42] High-Ene gy Ba e y Technologies,TheFa aday Ins ., Camb idge, U.K., 2020. [43] EnPowe . Accessed: Jul. 10, 2021. [Online]. A ailable: h ps://www.enpowe inc.com/ [44] J. Janek and W. G. Zeie , “A solid u u e o ba e y de elopmen ,” Na u e Ene gy, ol.1,no.9, Sep. 2016, A . no. 16141. [45] B. Dunn, H. Kama h, and J.-M. Ta ascon, “Elec ical ene gy s o age o he g id: A ba e y o choices,” Science, ol. 334, no. 6058, pp. 928–935, No . 2011. [46] Q. Liu e al., “App oaching he capaci y limi o li hium cobal oxide in li hium ion ba e ies ia lan hanum and aluminium doping,” Na u e Ene gy, ol. 3, no. 11, pp. 936–943, No . 2018. [47] P. Simon, Y. Gogo si, and B. Dunn, “Whe e do ba e ies end and supe capaci o s begin?” Science, ol. 343, no. 6176, pp. 1210–1211, Ma . 2014. [48] M. Keppele and M. S ini asan, “In e acial phenomena/capaci ies beyond con e sion eac ion occu ing in nano-sized ansi ion-me al-oxide-based nega i e elec odes in li hium-ion ba e ies: A e iew,” ChemElec oChem, ol. 4, no. 11, pp. 2727–2754, No . 2017. [49] Y. Gogo si and P. Simon, “T ue pe o mance me ics in elec ochemical ene gy s o age,” Science, ol. 334, no. 6058, pp. 917–918, No . 2011. [50] A.Sak i,J.J.Michalek,E.R.H.Fuchs,and J. F. Whi ac e, “A echno-economic analysis and op imiza ion o li-ion ba e ies o ligh -du y passenge ehicle elec i ica ion,” J. Powe Sou ces, ol. 273, pp. 966–980, Jan. 2015. [51] N. Ki ne , O. Schmid , I. S a ell, and D. M. Kammen, “G id-scale ene gy s o age,” in Technological Lea ning in he T ansi ion o a Low-Ca bon Ene gy Sys em.NewYo k,NY,USA: Academic, 2020, pp. 119–143, ch. 8. [52] T. Bowen, I. Che nyakho skiy, K. Xu, S. Gadzanku, and K. Coney, “USAID g id-scale ene gy s o age echnologies p ime ,” Na . Renew. Ene gy Lab., Golden, CO, USA, Tech. Rep. NREL/TP-6A20-76097, 2021. [53] A. Webe , “Fuel lexibili y o solid oxide uel cells,” Fuel Cells, ol. 21, no. 5, pp. 440–452, Aug. 2021. [54] W. Cole and A. W. F azie , “Cos p ojec ions o u ili y-scale ba e y s o age,” NREL, Golden, CO, USA, Tech. Rep. NREL/TP-6A20-73222, 2019. [55] B. Nyk is , F. Sp ei, and M. Nilsson, “Assessing he p og ess owa d lowe p iced long ange ba e y elec ic ehicles,” Ene gy Policy, ol. 124, pp. 144–155, Jan. 2019. [56] S. Sa yapal, “Hyd ogen and uel cells o e iew,” p esen ed a he DLA Wo ldwide Ene gy Con ., Na ional Ha bo , MD, USA, Ap . 12, 2017. Accessed: Feb. 27, 2022. [Online]. A ailable: h ps://ene gy.go /si es/p od/ iles/2017/06/ 34/ c oh2- c-o e iew-dla-wo ldwide-ene gy- con -2017-sa yapal.pd [57] Eu opean Associa ion o S o age o Ene gy (EASE)—Ac i i y Repo 2014,EASE, San F ancisco, CA, USA, 2014. [58] Eu opean Ene gy S o age Technology De elopmen Roadmap-2017 Upda e, EASE, San F ancisco, CA, USA, 2017. [59] X.Luo,J.Wang,M.Doone ,andJ.Cla ke, “O e iew o cu en de elopmen in elec ical ene gy s o age echnologies and he applica ion po en ial in powe sys em ope a ion,” Appl. Ene gy, ol. 137, pp. 511–536, Jan. 2015. [60] K.B adbu y,L.P a son,andD.Pa i¯no-Eche e i, “Economic iabili y o ene gy s o age sys ems based on p ice a bi age po en ial in eal- ime U.S. Elec ici y ma ke s,” Appl. Ene gy, ol. 114, pp. 512–519, Feb. 2014. [61] M. Salles, J. Huang, M. Aziz, and W. Hogan, “Po en ial a bi age e enue o ene gy s o age sys ems in PJM,” Ene gies, ol. 10, no. 8, p. 1100, Jul. 2017. [62] X. Wu, J. Zhao, and A. Conejo, “Op imal ba e y sizing o equency egula ion and ene gy a bi age,” IEEE T ans. Powe Del., ol.37,no.3, pp. 2016–2023, Jun. 2021. [63] Z. Wang and S. Wang, “G id powe peak sha ing and alley illing using ehicle- o-g id sys ems,” IEEE T ans. Powe Del., ol. 28, no. 3, pp. 1822–1829, Jul. 2013. [64] Z.Hong,Z.Wei,J.Li,andX.Han,“Ano el capaci y demand analysis me hod o ene gy s o age sys em o peak sha ing based on da a-d i en,” J. Ene gy S o age, ol. 39, Jul. 2021, A . no. 102617. [65] H. Ib ahim, A. Ilinca, and J. Pe on, “Ene gy s o age sys ems—Cha ac e is ics and compa isons,” Renew. Sus ain. Ene gy Re ., ol.12, no. 5, pp. 1221–1250, Jun. 2008. [66] P.Iliadis,S.N omalis,K.A sonios,A.Nesiadis, N. Nikolopoulos, and P. G ammelis, “Ene gy managemen and echno-economic assessmen o a p edic i e ba e y s o age sys em applying a load le elling ope a ional s a egy in island sys ems,” In . J. Ene gy Res., ol.45,no.2, pp. 2709–2727, Feb. 2021. [67] P.Denholm,E.Ela,B.Ki by,andM.Milligan, “Role o ene gy s o age wi h enewable elec ici y gene a ion,” Na . Renew. Ene gy Lab, Golden, CO, USA, Tech. Rep. NREL/TP-6A2-47187, 2010. [68] A. Ka ga ian, G. Hug, and J. Mohammadi, “A mul i- ime scale co-op imiza ion me hod o sizing o ene gy s o age and as - amping gene a ion,” IEEE T ans. Sus ain. Ene gy, ol.7, no. 4, pp. 1351–1361, Oc . 2016. [69] N. S. Go e i, E. Hi inge , B. Se gi, and I. L. Aze edo, “How does new ene gy s o age a ec he ope a ion and e enue o exis ing gene a ion?” Appl. Ene gy, ol. 285, Ma . 2021, A . no. 116383. [70] C. Li e al., “Me hod o he ene gy s o age con igu a ion o wind powe plan s wi h ene gy s o age sys ems used o black-s a ,” Ene gies, ol. 11, no. 12, p. 3394, Dec. 2018. [71] J.Li,H.You,J.Qi,M.Kong,S.Zhang,and H. Zhang, “S a i ied op imiza ion s a egy used o es o a ion wi h pho o ol aic-ba e y ene gy s o age sys ems as black-s a esou ces,” IEEE Access, ol. 7, pp. 127339–127352, 2019. [72] W. Liu and Y. Liu, “Hie a chical model p edic i e con ol o wind a m wi h ene gy s o age sys em o equency egula ion du ing black-s a ,” In . J. Elec . Powe Ene gy Sys ., ol. 119, Jul. 2020, A . no. 105893. [73] A. Cas illo and D. F. Gayme, “G id-scale ene gy s o age applica ions in enewable ene gy in eg a ion: A su ey,” Ene gy Con e s. Manage., ol. 87, pp. 885–894, No . 2014. [74] F. Mohamad, J. Teh, and C.-M. Lai, “Op imum alloca ion o ba e y ene gy s o age sys ems o powe g id enhanced wi h sola ene gy,” Ene gy, ol. 223, May 2021, A . no. 120105. [75] S. A. Abdel azek and S. Kamalasadan, “In eg a ed PV capaci y i ming and ene gy ime shi ba e y ene gy s o age managemen using ene gy-o ien ed op imiza ion,” IEEE T ans. Ind. Appl., ol. 52, no. 3, pp. 2607–2617, May 2016. [76] H. Bel an, J. Ca do-Mio a, J. Sega a-Tama i , and E. Pé ez, “Ba e y size de e mina ion o pho o ol aic capaci y i ming using deep lea ning i adiance o ecas s,” J. Ene gy S o age, ol.33, Jan. 2021, A . no. 102036. [77] L. Meng e al., “Fas equency esponse om ene gy s o age sys ems—A e iew o g id s anda ds, p ojec s and echnical issues,” IEEE T ans. Sma G id, ol. 11, no. 2, pp. 1566–1581, Ma . 2019. [78] M. Zubiaga, A. Sanchez-Ruiz, E. Olea, E. Unamuno, A. Bilbao, and J. A za, “Powe capabili y bounda ies o an in e e p o iding mul iple g id suppo se ices,” Ene gies, ol. 13, no. 17, p. 4314, Aug. 2020. [79] A. Peña Asensio, F. Gonzalez-Longa , S. A nal es, and J. L. Rod íguez-Amenedo, “Analysis o he con e e synch onizing me hod o he con ibu ion o ba e y ene gy s o age sys ems o ine ia emula ion,” Ene gies, ol. 13, no. 6, p. 1478, Ma . 2020. [80] A. Oudalo , D. Cha ouni, and C. Ohle , “Op imizing a ba e y ene gy s o age sys em o p ima y equency con ol,” IEEE T ans. Powe Sys ., ol. 22, no. 3, pp. 1259–1266, Aug. 2007. [81] M. Yoon e al., “U iliza ion o ene gy s o age sys em o equency egula ion in la ge-scale ansmission sys em,” Ene gies, ol. 12, no. 20, p. 3898, Oc . 2019. [82] F. Cale o, C. A. Caniza es, and K. Bha acha ya, “Dynamic modeling o ba e y ene gy s o age and applica ions in ansmission sys ems,” IEEE T ans. Sma G id, ol. 12, no. 1, pp. 589–598, Jan. 2020. [83] FLEXITRANSTORE: Eu opean Union’s Ho izon 2020 P ojec . Accessed: Jun. 18, 2022. [Online]. A ailable: h p://www. lexi ans o e.eu/ [84] J. M. Eye , “Elec ic u ili y ansmission and dis ibu ion upg ade de e al bene i s om modula elec ici y s o age: A s udy o he DOE ene gy s o age sys ems p og am,” Sandia Na . Labo a o ies, Albuque que, NM, USA, Tech. Rep. SAND2009-4070, 2009. [85] M.M.Rahman,A.O.Oni,E.Gemechu,and A. Kuma , “The de elopmen o echno-economic models o he assessmen o u ili y-scale 416 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies elec o-chemical ba e y s o age sys ems,” Appl. Ene gy, ol. 283, Feb. 2021, A . no. 116343. [86] M.I.Cheha deh,H.Lesani,M.K.Zadeh,and E. M. Sia ashi, “An op imal con ol s a egy o alle ia e sub-synch onous esonance in VSC-HVDC sys ems,” in P oc. 2nd In . Con . Powe Elec on. In ell. T ansp. Sys . (PEITS), Dec. 2009, pp. 250–255. [87] B.Fang,Y.Jiao,L.Dong,W.Zhou,andH.Nian, “Using i ual synch onous gene a o con ol based ene gy s o age o enhance he s abili y o sending e minal in LCC-HVDC sys em,” in P oc. 4 h In . Con . HVDC (HVDC), No . 2020, pp. 304–309. [88] B. P. Robe s and C. Sandbe g, “The ole o ene gy s o age in de elopmen o sma g ids,” P oc. IEEE, ol. 99, no. 6, pp. 1139–1144, Jun. 2011. [89] E. Gal an, P. Mandal, and Y. Sang, “Ne wo ked mic og ids wi h oo - op sola PV and ba e y ene gy s o age o imp o e dis ibu ion g ids esilience o na u al disas e s,” In . J. Elec . Powe Ene gy Sys ., ol. 123, Dec. 2020, A . no. 106239. [90] Y.Wang,K.T.Tan,X.Y.Peng,andP.L.So, “Coo dina ed con ol o dis ibu ed ene gy-s o age sys ems o ol age egula ion in dis ibu ion ne wo ks,” IEEE T ans. Powe Del., ol. 31, no. 3, pp. 1132–1141, Jun. 2015. [91] M.S ecca,L.R.Elizondo,T.B.Soei o,P.Baue , and P. Palensky, “A comp ehensi e e iew o he in eg a ion o ba e y ene gy s o age sys ems in o dis ibu ion ne wo ks,” IEEE Open J. Ind. Elec on. Soc., ol. 1, pp. 46–65, 2020. [92] R. Tapia-Sánchez, A. Medina-Rios, N. M. Salgado-He e a, D. G anados-Liebe man, J. R. Rod íguez-Rod íguez, and J. L. Guillén-Agui e, “Reac i e powe compensa ion in dis ibu ion sys ems h ough he DSTATCOM in eg a ion based on he bond g aph domain,” A abianJ.Sci.Eng., ol. 45, no. 3, pp. 1435–1446, Ma . 2020. [93] M. U. Hashmi, L. Pe ei a, and A. Busic, “Ene gy s o age in madei a, po ugal: Co-op imizing o a bi age, sel -su iciency, peak sha ing and ene gy backup,” in P oc. IEEE Milan Powe Tech, Jun. 2019, pp. 1–6. [94] Y. Yoon and Y.-H. Kim, “Cha ge scheduling o an ene gy s o age sys em unde ime-o -use p icing and a demand cha ge,” Sci. Wo ld J., ol. 2014, Oc . 2014, A . no. 937329. [95] J. Mundackal, A. C. Va ghese, P. S eekala, and V. Reshmi, “G id powe quali y imp o emen and ba e y ene gy s o age in wind ene gy sys ems,” in P oc. Annu. In . Con . Eme g. Res. A eas In . Con . Mic oelec on., Commun. Renew. Ene gy, Jun. 2013, pp. 1–6. [96] M.Nazemi,M.Moeini-Agh aie, M. Fo uhi-Fi uzabad, and P. Dehghanian, “Ene gy s o age planning o enhanced esilience o powe dis ibu ion ne wo ks agains ea hquakes,” IEEE T ans. Sus ain. Ene gy, ol. 11, no. 2, pp. 795–806, Ap . 2019. [97] M. Fe a o, G. B unaccini, F. Se gi, D. Aloisio, N. Randazzo, and V. An onucci, “F om unin e up ible powe supply o esilien sma mic o g id: The case o a ba e y s o age a elecommunica ion s a ion,” J. Ene gy S o age, ol. 28, Ap . 2020, A . no. 101207. [98] S. K. Chaudha y, A. F. Cupe ino, R. Teodo escu, and J. R. S ensson, “Benchma king o modula mul ile el con e e opologies o ES-STATCOM ealiza ion,” Ene gies, ol. 13, no. 13, p. 3384, Jul. 2020. [99] H. S. K ishnamoo hy, D. Rana, and P.N.Enje i, “A new wind u bine gene a o /ba e y ene gy s o age u ili y in e ace con e e opology wi h medium- equency ans o me ,” in P oc. 28 h Annu. IEEE Appl. Powe Elec on. Con . Expo. (APEC), Ma . 2013, pp. 2218–2224. [100] C.-S. Moo, K. S. Ng, and Y.-C. Hsieh, “Pa allel ope a ion o ba e y powe modules,” IEEE T ans. Ene gy Con e s., ol. 23, no. 2, pp. 701–707, Jun. 2008. [101] H. Chen, L. Zhang, and Y. Han, “Sys em- heo e ic analysis o a class o ba e y equaliza ion sys ems: Ma hema ical modeling and pe o mance e alua ion,” IEEE T ans. Veh. Technol., ol. 64, no. 4, pp. 1445–1457, Ap . 2015. [102] S. D. G. Jayasinghe, D. M. Vila hgamuwa, and U. K. Madawala, “A ba e y ene gy s o age in e ace o wind powe sys ems wi h he use o g id side in e e ,” in P oc. IEEE Ene gy Con e s. Cong . Expo., Sep. 2010, pp. 3786–3791. [103] S. Bu us e a, J. Pou, S. Ceballos, I. Ma ino, J. Á. Alzola, and V. G. Agelidis, “Capaci o ol age balancing in a h ee-le el-con e e -based ene gy s o age sys em,” EPE J., ol. 23, no. 4, pp. 14–22, Dec. 2013. [104] L. M. G zesiak and J. G. Tomasik, “Au onomous powe gene a ing sys em wi h mul i-le el con e e s,” in P oc. 32nd Annu. Con . IEEE Ind. Elec on., No . 2006, pp. 2815–2820. [105] Y. Cheng, C. Qian, M. L. C ow, S. Peka ek, and S. A ci y, “A compa ison o diode-clamped and cascaded mul ile el con e e s o a STATCOM wi h ene gy s o age,” IEEE T ans. Ind. Elec on., ol. 53, no. 5, pp. 1512–1521, Oc . 2006. [106] Y. Cheng and M. L. C ow, “A diode-clamped mul i-le el in e e o he S a Com/BESS,” in P oc. IEEE Powe Eng. Soc. Win e Mee ing. Con ., Jan. 2002, pp. 470–475. [107] J. Pou, R. Pindado, D. Bo oye ich, and P. Rod iguez, “E alua ion o he low- equency neu al-poin ol age oscilla ions in he h ee-le el in e e ,” IEEE T ans. Ind. Elec on., ol. 52, no. 6, pp. 1582–1588, Dec. 2005. [108] P. Ba bosa, P.S eime ,J.S einke, M. Winkelnkempe , and N. Celano ic, “Ac i e-neu al-poin -clamped (ANPC) mul ile el con e e echnology,” in P oc. Eu . Con . Powe Elec on. Appl., 2005, pp. 1–10. [109] A.E xebe ia,I.Vechiu,S.Baudoin,H.Camblong, and J.-M. Vinassa, “Con ol o a hyb id ene gy s o age sys em using a h ee le el neu al poin clamped con e e ,” in P oc. 38 h Annu. Con . IEEE Ind. Elec on. Soc., Oc . 2012, pp. 3400–3405. [110] G. Liang e al., “Analy ical de i a ion o in e submodule ac i e powe dispa i y limi s in modula mul ile el con e e -based ba e y ene gy s o age sys ems,” IEEE T ans. Powe Elec on., ol. 36, no. 3, pp. 2864–2874, Ma . 2021. [111] S. Thomas, M. S ieneke , and R. W. D. Doncke , “De elopmen o a modula high-powe con e e sys em o ba e y ene gy s o age sys ems,” in P oc. IEEE Eu . Con . Powe Elec on. Appl., Ma . 2011, pp. 1–10. [112] M. S ieneke , S. P.Engel,H.S agge,and R. W. De Doncke , “Op imiza ion o he pulse-wid h-modula ion s a egy o edundan and non- edundan mul i-le el cascaded-cell con e e s,” in P oc. IEEE Ene gy Con e s. Cong . Expo., Sep. 2013, pp. 101–108. [113] L. Maha jan, T. Yamagishi, and H. Akagi, “Ac i e-powe con ol o indi idual con e e cells o a ba e y ene gy s o age sys em based on a mul ile el cascade PWM con e e ,” IEEE T ans. Powe Elec on., ol. 27, no. 3, pp. 1099–1107, Ma . 2012. [114] N. Kawakami e al., “De elopmen o a 500-kW modula mul ile el cascade con e e o ba e y ene gy s o age sys ems,” IEEE T ans. Ind. Appl., ol. 50, no. 6, pp. 3902–3910, No ./Dec. 2014. [115] T. Soong and P. W. Lehn, “E alua ion o eme ging modula mul ile el con e e s o BESS applica ions,” IEEE T ans. Powe Del., ol. 29, no. 5, pp. 2086–2094, Oc . 2014. [116] M.Vasiladio is,N.Che ix,andA.Ru e ,“Impac o g id asymme ies on he ope a ion and capaci i e ene gy s o age design o modula mul ile el con e e s,” IEEE T ans. Ind. Elec on., ol. 62, no. 11, pp. 6697–6707, No . 2015. [117] G. Liang e al., “E ec o capaci o ol age ipples on submodule ac i e powe con ol limi s o cascaded mul ile el con e e s,” IEEE T ans. Ind. Elec on., ol. 69, no. 6, pp. 5952–5961, Jun. 2022. [118] M. A. Pe ez, S. Be ne , J. Rod iguez, S. Kou o, and R. Lizana, “Ci cui opologies, modeling, con ol schemes, and applica ions o modula mul ile el con e e s,” IEEE T ans. Powe Elec on., ol.30, no. 1, pp. 4–17, Jan. 2014. [119] T. Jimichi, H. Fuji a, and H. Akagi, “Design and expe imen a ion o a dynamic ol age es o e capable o signi ican ly educing an ene gy-s o age elemen ,” IEEE T ans. Ind. Appl., ol. 44, no. 3, pp. 817–825, Jun. 2008. [120] S. P. Engel, M. S ieneke , N. Sol au, S. Rabiee, H. S agge, and R. W. De Doncke , “Compa ison o he modula mul ile el DC con e e and he dual-ac i e b idge con e e o powe con e sion in HVDC and MVDC g ids,” IEEE T ans. Powe Elec on., ol. 30, no. 1, pp. 124–137, Jan. 2015. [121] J. E. Hube and J. W. Kola , “Applicabili y o solid-s a e ans o me s in oday’s and u u e dis ibu ion g ids,” IEEE T ans. Sma G id, ol. 10, no. 1, pp. 317–326, Jan. 2019. [122] S. A. M. Saleh e al., “Solid-s a e ans o me s o dis ibu ion sys ems—Pa I: Technology and cons uc ion,” IEEE T ans. Ind. Appl., ol.55, no. 5, pp. 4524–4535, Sep. 2019. [123] X. She, A. Q. Huang, and R. Bu gos, “Re iew o solid-s a e ans o me echnologies and hei applica ion in powe dis ibu ion sys ems,” IEEE J. Eme g. Sel. Topics Powe Elec on., ol. 1, no. 3, pp. 186–198, Sep. 2013. [124] F.B iz,M.Lopez,A.Rod iguez,andM.A ias, “Modula powe elec onic ans o me s: Modula mul ile el con e e e sus cascaded H-b idge solu ions,” IEEE Ind. Elec on. Mag., ol.10,no.4, pp. 6–19, Dec. 2016. [125] C. Kuma , R. Zhu, G. Bu icchi, and M. Lise e, “Sizing and SOC managemen o a sma - ans o me -based ene gy s o age sys em,” IEEE T ans. Ind. Elec on., ol.65,no.8, pp. 6709–6718, Aug. 2018. [126] B.Zhao,S.Qiang,W.Liu,andY.Sun,“O e iew o dual-ac i e-b idge isola ed bidi ec ional DC-DC con e e o high- equency-link powe -con e sion sys em,” IEEE T ans. Powe Elec on., ol. 29, no. 8, pp. 4091–4106, Aug. 2014. [127] A. Q. Huang, Q. Zhu, L. Wang, and L. Zhang, “15 kV SiC MOSFET: An enabling echnology o medium ol age solid s a e ans o me s,” CPSS T ans. Powe Elec on. Appl., ol. 2, no. 2, pp. 118–130, Jun. 2017. [128] H. Akagi, S. I. Kinouchi, and Y. Miyazaki, “Bidi ec ional isola ed dual-ac i e-b idge (DAB) DC-DC con e e s using 1.2-kV 400-A SiC-MOSFET dual modules,” CPSS T ans. Powe Elec on. Appl., ol. 1, no. 1, pp. 33–40, Dec. 2016. [129] L. Zhang, Y. Tang, S. Yang, and F. Gao, “Decoupled powe con ol o a modula -mul ile el-con e e -based hyb id AC–DC g id in eg a ed wi h hyb id ene gy s o age,” IEEE T ans. Ind. Elec on., ol.66,no.4, pp. 2926–2934, Ap . 2019. [130] H. Baya and A. Yazdani, “A hyb id MMC-based pho o ol aic and ba e y ene gy s o age sys em,” IEEE Powe Ene gy Technol. Sys . J., ol.6,no.1, pp. 32–40, Ma . 2019. [131] G id Connec ion o Ene gy Sys ems Via In e e s, S anda d AS/NZS 4777.2:2015, 2015. [132] Technische und O ganisa o ische Regeln Fu Be eibe und Benu ze Vonne zen, TOR-Haup abschni D4, Vienna, Aus ia, 2016. [133] IEEE S anda d o In e connec ion and In e ope abili y o Dis ibu ed Ene gy Resou ces Wi h Associa ed Elec ic Powe Sys ems In e aces, IEEE S anda d 1547-2018 (Re ision o IEEE S d 1547-2003), 2018. [134] Gene a o s Connec ed o he Low-Vol age Dis ibu ion Ne wo k—Technical Requi emen s o he Connec ion o and Pa allel Ope a ion Wi h Low-Vol age Dis ibu ion Ne wo ks,S anda dVDE Re . VDE-AR-N 4105, 2018. [135] Re e ence Technical Rules o he Connec ion o Ac i e and Passi e Use s o he LV Elec ical U ili ies, documen CEI 0-21, 2019. [136] Technical Regula ion 3.2.2 o Powe Plan s Abo e 11 kW, documen Technical egula ion 3.2.2, 2016. [137] L. Meng e al., “Fas equency esponse om Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 417 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies ene gy s o age sys ems—A e iew o g id s anda ds, p ojec s and echnical issues,” IEEE T ans. Sma G id, ol. 11, no. 2, pp. 1566–1581, Ma . 2020. [138] G. Li, Y. Chen, A. Luo, and H. Wang, “The se o g id-suppo ing unc ionali ies ha a BESS can p o ide is expansi e, conside ing app op ia e in e e sizing, con ol unc ions implemen a ion and de ailed in eg a ion s udies. BESS can enhance sys em s eng h, bo h in e ms o ol age managem,” IEEE T ans. Ind. In o ma ., ol. 16, no. 9, pp. 5835–5845, Jan. 2020. [139] J. Glassmi e, H. Bi a a , S. Che e a skiy, and D. Cicio, “Using ene gy s o age o s abilise g ids and inc ease e enues,” CIRED-Open Access P oc. J., ol. 2020, no. 1, pp. 484–486, Jan. 2020. [140] M. R. Rapizza and S. M. Cane ese, “Fas equency egula ion and syn he ic ine ia in a powe sys em wi h high pene a ion o enewable ene gy sou ces: Op imal design o he equi ed quan i ies,” Sus ain. Ene gy, G ids Ne w., ol.24, Dec. 2020, A . no. 100407. [141] R.Rosso,X.Wang,M.Lise e,X.Lu,and S. Engelken, “G id- o ming con e e s: Con ol app oaches, g id-synch oniza ion, and u u e ends—A e iew,” IEEE Open J. Ind. Appl., ol.2, pp. 93–109, 2021. [142] J. Fang, H. Li, Y. Tang, and F. Blaabje g, “On he ine ia o u u e mo e-elec onics powe sys ems,” IEEE J. Eme g. Sel. Topics Powe Elec on., ol.7, no. 4, pp. 2130–2146, Dec. 2019. [143] M. Cespedes and J. Sun, “Impedance modeling and analysis o g id-connec ed ol age-sou ce con e e s,” IEEE T ans. Powe Elec on., ol.29, no. 3, pp. 1254–1261, Ma . 2014. [144] J. Alipoo , Y. Miu a, and T. Ise, “Powe sys em s abiliza ion using i ual synch onous gene a o wi h al e na ing momen o ine ia,” IEEE J. Eme g. Sel. Topics Powe Elec on., ol. 3, no. 2, pp. 451–458, Jun. 2015. [145] ARENA Insigh s Webina . Aus alian Renewable Ene gy Agency. Accessed: Oc . 30, 2021. [Online]. A ailable: h ps://a ena.go . au/asse s/2021/06/a ena-insigh s-webina - ad anced-in e e s-p esen a ions.pd [146] X. Liang, C. Andalib-Bin-Ka im, W. Li, M. Mi olo, andM.N.S.K.Shabbi ,“Adap i e i ual impedance-based eac i e powe sha ing in i ual synch onous gene a o con olled mic og ids,” IEEE T ans. Ind. Appl., ol. 57, no. 1, pp. 46–60, Jan. 2021. [147] J.He,Y.W.Li,D.Bosnjak,andB.Ha is, “In es iga ion and ac i e damping o mul iple esonances in a pa allel-in e e -based mic og id,” IEEE T ans. Powe Elec on., ol. 28, no. 1, pp. 234–246, Jan. 2013. [148] Dal ymple ESCRI-SA Ba e y P ojec .Elec ane . Accessed: Oc . 30, 2021. [Online]. A ailable: h ps://www.elec ane .com.au/elec ane s- ba e y-s o age-p ojec / [149] A. Kuma esan, H. D. Ta i, N. K. Kandasamy, G. G. Fa i a , J. Pou, and T. Subbaiyan, “Flexible powe poin acking o sola pho o ol aic sys ems using secan me hod,” IEEE T ans. Powe Elec on., ol. 36, no. 8, pp. 9419–9429, Aug. 2021. [150] B.-I. C aciun, T. Ke ekes, D. Se a, and R. Teodo escu, “F equency suppo unc ions in la ge PV powe plan s wi h ac i e powe ese es,” IEEE J. Eme g. Sel. Topics Powe Elec on., ol. 2, no. 4, pp. 849–858, Dec. 2014. [151] A.F.Hoke,M.Shi azi,S.Chak abo y,E.Muljadi, and D. Maksimo ic, “Rapid ac i e powe con ol o pho o ol aic sys ems o g id equency suppo ,” IEEE J. Eme g. Sel. Topics Powe Elec on., ol. 5, no. 3, pp. 1154–1163, Sep. 2017. [152] E.I.Ba zelis,S.A.Papa hanassiou,andB.C.Pal, “PV sys em con ol o p o ide ac i e powe ese es unde pa ial shading condi ions,” IEEE T ans. Powe Elec on., ol. 33, no. 11, pp. 9163–9175, No . 2018. [153] A. Sangwongwanich, Y. Yang, and F. Blaabje g, “A senso less powe ese e con ol s a egy o wo-s age g id-connec ed PV sys ems,” IEEE T ans. Powe Elec on., ol. 32, no. 11, pp. 8559–8569, No . 2017. [154] H.W.Yan,A.Na ang,H.D.Ta i,G.G.Fa i a , S. Ceballos, and J. Pou, “Minimizing ene gy s o age u iliza ion in a s and-alone DC mic og id using pho o ol aic lexible powe con ol,” IEEE T ans. Sma G id, ol. 12, no. 5, pp. 3755–3764, Sep. 2021. [155] H.W.Yan,A.Na ang,H.D.Ta i,G.G.Fa i a , and J. Pou, “Reduced ba e y usage in a hyb id ba e y and pho o ol aic s and-alone DC mic og id wi h lexible powe poin acking,” in P oc. IEEE ECCE, Oc . 2020, pp. 3894–3899. [156] J. F i h. (Sep. 14, 2021). Bloombe g. Accessed: Oc . 13, 2021. [Online]. A ailable: h ps://www.bloombe g.com/news/newsle e s/ 2021-09-14/e -ba e y-p ices- isk- e e sing- downwa d- end-as-me als-su ge [157] S.Alshah ani,M.Khalid,andM.Almuhaini, “Elec ic ehicles beyond ene gy s o age and mode n powe ne wo ks: Challenges and applica ions,” IEEE Access, ol.7, pp. 99031–99064, 2019. [158] S. Naza i, F. Bo elli, and A. S e anopoulou, “Elec ic ehicles o sma buildings: A su ey on applica ions, ene gy managemen me hods, and ba e y deg ada ion,” P oc. IEEE, ol. 109, no. 6, pp. 1128–1144, Dec. 2021. [159] E. Hossain, D. Mu augh, J. Mody, H. M. R. Fa uque, M. S. H. Sunny, and N. Mohammad, “A comp ehensi e e iew on second-li e ba e ies: Cu en s a e, manu ac u ing conside a ions, applica ions, impac s, ba ie s & po en ial solu ions, business s a egies, and policies,” IEEE Access, ol. 7, pp. 73215–73252, 2019. [160] D. P oc o . (2018). EV Ba e ies Repu posed o Ene gy S o age. Accessed: Oc . 13, 2021. [Online]. A ailable: h ps://www.powe mag.com/e - ba e ies- epu posed- o -ene gy-s o age/ [161] B. Bibaka and H. Tekine -Mo˘gulkoç, “A comp ehensi e analysis o ehicle o g id (V2G) sys ems and schola ly li e a u e on he applica ion o such sys ems,” Renew. Ene gy Focus, ol.36, pp. 1–10, Ma . 2021. [162] B. K. So acool and R. F. Hi sh, “Beyond ba e ies: An examina ion o he bene i s and ba ie s o plug-in hyb id elec ic ehicles (PHEVs) and a ehicle- o-g id (V2G) ansi ion,” Ene gy Policy, ol. 37, no. 3, pp. 1095–1103, Ma . 2009. [163] A. B. B i o and K. K annich. Elek obi . Accessed: Ma . 2, 2022. [Online]. A ailable: h ps://www.elek obi .com/ ends/ ehicle- o- g id- echnology/ [164] G eenpeace. Accessed: Ma . 2, 2022. [Online]. A ailable: h ps://www.g eenpeace. o g/eas asia/p ess/6175/g eenpeace- epo - oubleshoo s-chinas-elec ic- ehicles-boom- highligh s-c i ical-supply- isks- o -li hium-ion- ba e ies/ [165] S. Amelang and B. Weh mann. (May 4, 2021). G een Resou ces, Reuse and Recycling a e Key o Cleane E-Ca Ba e ies. Accessed: Ma . 2, 2022. [Online]. A ailable: h ps://www.cleanene gywi e.o g/ ac shee s/ g een- esou ces- euse-and- ecycling-a e-key- cleane -e-ca -ba e ies [166] C. Hampel. (Jan. 29, 2022). Elec i e. Accessed: Ma . 2, 2022. [Online]. A ailable: h ps://www.elec i e.com/2022/01/29/ba e y- euse- ecycling-expands- o-scale-in-china/ [167] E. Fan e al., “Sus ainable ecycling echnology o li-ion ba e ies and beyond: Challenges and u u e p ospec s,” Chem. Re ., ol. 120, no. 14, pp. 7020–7063, Jul. 2020. [168] J. Kumagai, “Momen um builds o li hium-ion ba e y ecycling: The goal is o p e en housands o ons o spen ba e ies om going o was e,” IEEE Spec ., ol. 58, no. 1, pp. 52–53, Jan. 2021. [169] G. Ha pe e al., “Recycling li hium-ion ba e ies om elec ic ehicles,” Na u e, ol. 575, no. 7781, pp. 75–86, 2019. [170] J. J. Roy e al., “G een ecycling me hods o ea li hium-ion ba e ies E-was e: A ci cula app oach o sus ainabili y,” Ad . Ma e ., p. 2103346. [Online]. A ailable: h ps://onlinelib a y. wiley.com/doi/abs/10.1002/adma.202103346, doi: 10.1002/adma.202103346. [171] M. P. Do, J. J. Roy, B. Cao, and M. S ini asan, “G een closed-loop ca hode egene a ion om spen NMC-based li hium-ion ba e ies h ough bioleaching,” ACS Sus ain. Chem. Eng., ol.10, no. 8, pp. 2634–2644, Feb. 2022. [172] M. A. Khan e al., “Seawa e elec olysis o hyd ogen p oduc ion: A solu ion looking o a p oblem?” Ene gy En i on. Sci., ol.14,no.9, pp. 4831–4839, 2021. [173] A. A. AlZah ani and I. Dince , “Modeling and pe o mance op imiza ion o a solid oxide elec olysis sys em o hyd ogen p oduc ion,” Appl. Ene gy, ol. 225, pp. 471–485, Sep. 2018. [174] I. Abadlia, M. Adjabi, and H. Bouze ia, “Sliding mode based powe con ol o g id-connec ed pho o ol aic-hyd ogen hyb id sys em,” In . J. Hyd ogen Ene gy, ol. 42, no. 47, pp. 28171–28182, No . 2017. [175] S. B uce e al., “Na ional hyd ogen oadmap,” CSIRO, Canbe a, ACT, Aus alia, Tech. Rep. EP184600, 2018. [176] C. J. Qua on and S. Samsa li, “Powe - o-gas o injec ion in o he gas g id: Wha can we lea n om eal-li e p ojec s, economic assessmen s and sys ems modelling?” Renew. Sus ain. Ene gy Re ., ol. 98, pp. 302–316, Dec. 2018. [177] H. Ba hélémy, “E ec s o p essu e and pu i y on he hyd ogen emb i lemen o s eels,” In . J. Hyd ogen Ene gy, ol. 36, no. 3, pp. 2750–2758, Feb. 2011. [178] A.Kle ke,C.H.Ch is ensen,J.K.Nø sko ,and T. Vegge, “Ammonia o hyd ogen s o age: Challenges and oppo uni ies,” J. Ma e . Chem., ol. 18, no. 20, pp. 2304–2310, 2008. [179] A.Mazza,E.Bompa d,andG.Chicco, “Applica ions o powe o gas echnologies in eme ging elec ical sys ems,” Renew. Sus ain. Ene gy Re ., ol. 92, pp. 794–806, Sep. 2018. [180] H. Renaudineau, A. M. Llo , R. Co es, C. A. Rojas, C. Res epo, and S. Kou o, “Pho o ol aic g een hyd ogen challenges and oppo uni ies: A powe elec onics pe spec i e,” IEEE Ind. Elec on. Mag., ol. 16, no. 1, pp. 31–41, Ma . 2022. [181] M. Wang, G. Wang, Z. Sun, Y. Zhang, and D. Xu, “Re iew o enewable ene gy-based hyd ogen p oduc ion p ocesses o sus ainable ene gy inno a ion,” Global Ene gy In e connec ion, ol.2, no. 5, pp. 436–443, Oc . 2019. [182] J. Gong, “A commen a y o g een hyd ogen in MIT echnology e iew 2021,” Fundam. Res., ol.1, no. 6, pp. 848–850, No . 2021. [183] DOE Global Ene gy S o age Da abase. Accessed: Feb. 25, 2022. [Online]. A ailable: h ps://sandia.go /ess- ssl/gesdb/public/p ojec s.h ml 418 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies ABOUT THE AUTHORS Glen G. Fa i a (Senio Membe , IEEE) ecei ed he B.Sc. deg ee in elec ical engi- nee ing om he Noshi ani Ins i u e o Technology, Babol, I an, in 2008, he M.Sc. deg ee in powe elec onics om he Uni e - si y o Teh an, Teh an, I an, in 2011, and he Ph.D. deg ee in elec ical enginee ing om he Uni e si y o New Sou h Wales, Sydney, NSW, Aus alia, in 2016. He is cu en ly a Senio Resea ch Fellow wi h he Ene gy Resea ch Ins i u e, Nanyang Technological Uni e si y (ERI@N), Singapo e. He is also a Co-Di ec o o he Powe Elec onics and Applica ions Resea ch Labo a o y, ERI@N, and a Co-Founde o SciLeap, Pe h, WA, Aus alia, which aims o p omo e esea ch in eg i y, acces- sibili y, and openness. His esea ch in e es s include enewable ene gy sys ems, high-powe con e e s, ene gy s o age, lexible ac ansmission sys ems (FACTS), and elec ic ehicles. William Manalas as, J ., was men o ed by he ALISTORE Eu opean Elec ochemis y Ne wo k, D . F ede ic Aguesse a CIC ene gi- GUNE,Ála a,Spain,andP o .JohnKilne a Impe ial College London, London, U.K. He is a ba e y scien is /enginee ac i e in he a eas o ad anced li hium-ion/li hium-me al ba e ies and aqueous mul i alen -ion ba - e ies. He is cu en ly a Resea ch Fellow wi h he Ene gy S o age Labo a o y, Nanyang Technological Uni e si y, Singapo e, in he g oup o P o . Madha i S ini asan. D . Manalas as, J ., was a ecipien o a JASSO G an , an E asmus Mundus Schola ship, and a CIC Ene gigune PhD Fellowship. Hossein Dehghani Ta i (Senio Membe , IEEE) ecei ed he B.Sc. and M.Sc. deg ees in elec ical enginee ing and powe sys em enginee ing om he Ami kabi Uni e si y o Technology, Teh an, I an, in 2009 and 2011, espec i ely, and he Ph.D. deg ee in elec i- cal enginee ing om Nanyang Technological Uni e si y, Singapo e, in 2018. F om Janua y 2018 o Ap il 2020, he was a Resea ch Fellow wi h Nanyang Technological Uni e si y, whe e he was wo king on he con ol o pho o ol aic sys ems o g id suppo . F om May 2020 o May 2021, he was a Senio Resea ch Associa e wi h he Uni e si y o New Sou h Wales, Sydney, NSW, Aus alia, whe e he wo ked on modeling and es ing comme cial pho o ol aic in e e s. He is cu en ly a Resea ch Fellow wi h he Depa men o Elec ical, Elec onic and Compu e Enginee ing, The Uni e si y o Wes e n Aus alia, Pe h, WA, Aus alia. His esea ch in e es includes he g id in eg a ion o enewable ene gy sou ces, in pa - icula , pho o ol aics, ene gy s o age, and he design and con ol o mul ile el powe con e e s. Sal ado Ceballos ecei ed he M.S. deg ee in physics om he Uni e si y o Can ab ia, San ande , Spain, in 2001, and he M.S. and Ph.D. deg ees in elec onic enginee ing om he Uni e si y o he Basque Coun y, Bilbao, Spain, in 2002 and 2008, espec i ely. Since 2002, he has been wi h Tecnalia, Basque Resea ch and Technology Alliance (BRTA), De io, Spain, whe e he is cu en ly a P incipal Resea che wi h he Ene gy, Clima e and U ban T ansi ion Uni . His esea ch in e es s include mul ile el con e e s o high- and medium- ol age applica ions, aul - ole an powe elec onic opologies, enewable ene gy sys ems, and powe sys ems wi h high pene a- ion o powe con e e s. Alain Sanchez-Ruiz (Senio Membe , IEEE) ecei ed he B.Sc. deg ee in elec onics enginee ing, he M.Sc. deg ee in au oma - ics and indus ial elec onics, and he Ph.D. deg ee in elec ical enginee ing om he Uni e si y o Mond agon, Mond agon, Spain, in 2006, 2009, and 2014, espec i ely. He joined Inge eam R&D Eu ope, Zamu- dio, Spain, in May 2014, whe e he is cu - en ly an R&D Enginee . F om Feb ua y 2012 o May 2012, he was a Visi ing Resea che wi h The Uni e si y o Tennessee, Knox ille, TN, USA. Since Janua y 2017, he has been a Lec u e wi h he Uni e si y o he Basque Coun y (UPV/EHU), Bilbao, Spain. His cu - en esea ch in e es s include modeling, modula ion, and con ol o powe con e e s, mul ile el opologies, ad anced modula ion echniques, high-powe mo o d i es, and g id- ied con e e s. Emma C. Lo ell ecei ed he Ph.D. deg ee om he Uni e si y o New Sou h Wales (UNSW), Sydney, NSW, Aus alia, in 2016, de eloped ca alys s o ca bon dioxide con- e sion (wi h a esea ch exchange a he Uni e si y o B emen, B emen, Ge many). He Ph.D. wo k ocused on de eloping nickel-based ca alys s o he ca bon dioxide (d y) e o ming o me hane. She is cu en ly a Lec u e a he School o Chemical Enginee ing, UNSW. He esea ch ocuses on de eloping no el ca alys s o a ange o applica ions; wi h a pa icula ocus on ene gy and en i- onmen al ca alysis. He cu en esea ch ocuses on de eloping ca aly ic ma e ials o a ange o di e en ene gy inpu s; his includes de eloping ca alys s o he pho o-/plasmon-enhanced he mal ca aly ic ca bon dioxide me hana ion, he plasma-ca aly ic ca bon dioxide me hana ion, and ni ogen ixa ion, as well as de el- oping de ec i e elec oca alysis o hyd ogen e olu ion eac ion and ca bon dioxide educ ion eac ions. D . Lo ell was a ecipien o he Women in Enginee ing Schola - ship o he du a ion o he s udies. Vol. 111, No. 4, Ap il 2023 |PROCEEDINGS OF THE IEEE 419 Fa i a e al.: G id-Connec ed ESSs: S a e-o - he-A and Eme ging Technologies Geo gios Kons an inou (Senio Membe , IEEE) ecei ed he B.Eng. deg ee in elec- ical and compu e enginee ing om he A is o le Uni e si y o Thessaloniki, Thessaloniki, G eece, in 2007, and he Ph.D. deg ee in elec ical enginee ing om he Uni e si y o New Sou h Wales (UNSW Sydney), Sydney, NSW, Aus alia, in 2012. F om 2013 o 2016, he was a Senio Resea ch Associa e wi h UNSW Sydney, whe e he was pa o he Aus alian Ene gy Resea ch Ins i u e. Since 2017, he has been wi h he School o Elec ical Enginee ing and Telecommunica ions, UNSW Sydney, whe e he is cu en ly a Senio Lec u e . His main esea ch in e es s include mul ile el con e e s, powe elec onics in high- ol age dc (HVdc), enewable ene gy, and ene gy s o age applica ions. D . Kons an inou is also an Associa e Edi o o IEEE TRANSACTIONS ON POWER ELECTRONICS, IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS,andIET Powe Elec onics. Ch is ophe D. Townsend (Membe , IEEE) ecei ed he B.E. and Ph.D. deg ees in elec- ical enginee ing om he Uni e si y o Newcas le, Callaghan, NSW, Aus alia, in 2009 and 2013, espec i ely. Subsequen ly, he spen h ee yea s wo k- ing a ABB Co po a e Resea ch, Väs e ås, Sweden, wo king on nex -gene a ion high- powe con e e echnologies. Since hen, he has held a ious pos doc o al esea ch posi ions, including a he Uni e si y o New Sou h Wales, Sydney, NSW, Aus alia, he Uni e si y o Newcas le, and Nanyang Technological Uni e si y, Singapo e. In 2019, he joined he Depa men o Elec ical, Elec- onic and Compu e Enginee ing, The Uni e si y o Wes e n Aus- alia, Pe h, WA, Aus alia, as a Senio Lec u e . He has au ho ed mo e han 50 published echnical pape s and has been in ol ed in se e al indus ial p ojec s and educa ional p og ams in he ield o powe elec onics. His esea ch in e es s include opolo- gies and modula ion s a egies o mul ile el con e e s applied in powe sys ems, enewable ene gy in eg a ion, and elec ic ehicle applica ions. D . Townsend is also a membe o he IEEE Powe Elec onics and Indus ial Elec onics Socie ies. Madha i S ini asan g adua ed om IIT Mad as, Chennai, India. She did he Ph.D. disse a ion on li hium-ion ba e ies a he Na ional Uni e si y o Singapo e, Singapo e. He esea ch ocuses on he syn hesis, ab ica ion, and applica ion o nanoscale ma e ials/a chi ec u esin imp o ing he pe - o mance o elec ochemical ene gy s o - age de ices, such as ad anced li hium-ion ba e ies, supe capaci o s, sodium-ion ba e ies, and mul i alen aqueous Zn/Al ba e ies. He esea ch is also on he ecycling o li hium-ion ba e ies e-was e by no el hyd ome allu gical ech- niques owa d a closed-loop app oach. D .S ini asanhaswonse e alp es igiousawa ds,including he 2019 Asia’s Top Sus ainabili y Supe women, he L’O eal o Women in Science Na ional Fellowships, he G ea Women o Ou Time gi en by The Singapo e Women’s Weekly magazine, and he NRF In es iga o ship Awa d awa ded o op scien is s in Singapo e by he Na ional Resea ch Founda ion (NRF). Josep Pou (Fellow, IEEE) ecei ed he B.S., M.S., and Ph.D. deg ees in elec i- cal enginee ing om he Technical Uni- e si y o Ca alonia (UPC)-Ba celona Tech, Ba celona, Spain, in 1989, 1996, and 2002, espec i ely. In 1990, he joined he Facul y o UPC as an Assis an P o esso , whe e he became an Associa e P o esso in 1993. F om Feb ua y 2013 o Augus 2016, he was a P o esso wi h he Uni e si y o New Sou h Wales (UNSW), Sydney, NSW, Aus alia. He is cu en ly a P o esso wi h Nanyang Technological Uni e si y (NTU), Singapo e, whe e he is also he Clus e Di ec o o Powe Elec onics o he Ene gy Resea ch Ins i u e a NTU (ERI@N) and a Co-Di ec o o he Rolls-Royce, NTU Co po a e Labo a o y. F om Feb ua y 2001 o Janua y 2002 and Feb ua y 2005 o Janua y 2006, he was a Resea che wi h he Cen e o Powe Elec onics Sys ems, Vi ginia Tech, Blacksbu g, VA, USA. F om Janua y 2012 o Janua y 2013, he was a Visi ing P o esso wi h he Aus alian Ene gy Resea ch Ins i u e, UNSW. He has au ho ed mo e han 410 published ech- nical pape s and has been in ol ed in se e al indus ial p ojec s and educa ional p og ams in he ield o powe elec onics. His esea ch in e es s include modula ion and con ol o powe con- e e s, mul ile el con e e s, enewable ene gy, ene gy s o age, powe quali y, high- ol age dc (HVdc) ansmission sys ems, and mo e-elec ical ai c a and essels. D . Pou ecei ed he 2018 IEEE Bimal Bose Awa d o Indus ial Elec onics Applica ions in Ene gy Sys ems. He is also an Associa e Edi o o he IEEE JOURNAL OF EMERGING AND SELECTED TOPICS IN POWER ELECTRONICS.Hewas heCo-Edi o -in-Chie andanAsso- cia e Edi o o he IEEE TRANSACTIONS ON Indus ial Elec onics. 420 PROCEEDINGS OF THE IEEE | Vol. 111, No. 4, Ap il 2023