隨(sui)著(zhu)全(quan)球能源(yuan)互聯網建設的(de)(de)推進,光伏、風電(dian)等可(ke)(ke)再生能源(yuan)發(fa)電(dian)將會迎(ying)來高(gao)速發(fa)展。而“十四五(wu)”期(qi)間將是我國實現碳達(da)峰的(de)(de)關鍵期(qi),可(ke)(ke)再生能源(yuan)比例(li)將持續提升,最終取代火力發(fa)電(dian)成(cheng)為(wei)主(zhu)力能源(yuan)。在火電(dian)占比逐漸下(xia)降、承(cheng)擔深度(du)調峰壓力巨大(da)的(de)(de)新形勢下(xia),儲能技術無疑是有(you)效緩解大(da)規模可(ke)(ke)再生能源(yuan)并網壓力的(de)(de)一種有(you)效技術手段。
儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)技術涉及領域非常廣泛(fan),按儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)方式可(ke)分(fen)為抽(chou)水蓄能(neng)(neng)(neng)(neng)(neng)(neng)、壓縮(suo)空氣儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)、飛輪儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)、重力儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)、電(dian)池(chi)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)、蓄熱(re)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)等,按應(ying)(ying)用(yong)場景則可(ke)分(fen)為電(dian)網側(ce)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)、電(dian)源側(ce)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)、用(yong)戶側(ce)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)。電(dian)源側(ce)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)主要包括集(ji)中(zhong)式新(xin)能(neng)(neng)(neng)(neng)(neng)(neng)源利用(yong)、調(diao)頻輔(fu)助(zhu)服(fu)務應(ying)(ying)用(yong)、調(diao)峰輔(fu)助(zhu)服(fu)務應(ying)(ying)用(yong)3種應(ying)(ying)用(yong)模式,在(zai)各種儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)方式中(zhong),除傳統的(de)抽(chou)水蓄能(neng)(neng)(neng)(neng)(neng)(neng)以外均可(ke)用(yong)于電(dian)源側(ce)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)。儲(chu)(chu)(chu)熱(re)技術具有更強的(de)調(diao)節能(neng)(neng)(neng)(neng)(neng)(neng)力和持續(xu)供給(gei)能(neng)(neng)(neng)(neng)(neng)(neng)力,在(zai)電(dian)源側(ce)儲(chu)(chu)(chu)能(neng)(neng)(neng)(neng)(neng)(neng)中(zhong)應(ying)(ying)用(yong)十分(fen)廣泛(fan)。
純太陽能光熱發電
在(zai)純(chun)太陽能(neng)(neng)熱(re)(re)(re)發(fa)(fa)電(dian)領域,儲(chu)(chu)熱(re)(re)(re)是(shi)(shi)核心技術之一(yi)。目(mu)前(qian),國(guo)際上(shang)已經(jing)建成運(yun)行和正在(zai)建設的(de)純(chun)太陽能(neng)(neng)熱(re)(re)(re)電(dian)站大多配置了儲(chu)(chu)熱(re)(re)(re)系統(tong)(tong)(tong)。用(yong)于光熱(re)(re)(re)發(fa)(fa)電(dian)的(de)儲(chu)(chu)熱(re)(re)(re)系統(tong)(tong)(tong)以熔融鹽儲(chu)(chu)熱(re)(re)(re)為主,儲(chu)(chu)熱(re)(re)(re)溫度可達500℃以上(shang)。儲(chu)(chu)熱(re)(re)(re)系統(tong)(tong)(tong)的(de)引(yin)入進一(yi)步提高了純(chun)太陽能(neng)(neng)熱(re)(re)(re)發(fa)(fa)電(dian)系統(tong)(tong)(tong)中太陽能(neng)(neng)貢獻度,優(you)化了系統(tong)(tong)(tong)性能(neng)(neng),以50MW太陽能(neng)(neng)光熱(re)(re)(re)塔式(shi)發(fa)(fa)電(dian)項目(mu)為例,有(you)研(yan)究(jiu)者分(fen)析了是(shi)(shi)否配備(bei)儲(chu)(chu)熱(re)(re)(re)系統(tong)(tong)(tong)時電(dian)站性能(neng)(neng)情(qing)況(kuang)。可見,配備(bei)儲(chu)(chu)熱(re)(re)(re)系統(tong)(tong)(tong)時的(de)電(dian)站性能(neng)(neng)明顯優(you)于無儲(chu)(chu)熱(re)(re)(re)系統(tong)(tong)(tong)。
圖:50MW光熱發電機組搭配儲熱前后性能對比
太陽能光熱-化石燃料互補發電
純太(tai)(tai)陽(yang)(yang)能(neng)熱發(fa)(fa)(fa)(fa)電(dian)可以實現完全(quan)清(qing)潔發(fa)(fa)(fa)(fa)電(dian),但對(dui)設備要求(qiu)較高(gao)且裝機容量(liang)受限,因此有研究(jiu)者設計了太(tai)(tai)陽(yang)(yang)能(neng)與化石(shi)燃(ran)料(liao)互(hu)補的(de)發(fa)(fa)(fa)(fa)電(dian)技術。太(tai)(tai)陽(yang)(yang)能(neng)與化石(shi)燃(ran)料(liao)熱互(hu)補發(fa)(fa)(fa)(fa)電(dian)做到(dao)了太(tai)(tai)陽(yang)(yang)能(neng)光熱和化石(shi)燃(ran)料(liao)的(de)取長補短,一方面化石(shi)燃(ran)料(liao)發(fa)(fa)(fa)(fa)電(dian)系統(tong)的(de)穩定性可以在一定程度上平抑太(tai)(tai)陽(yang)(yang)能(neng)輻照頻繁波動(dong)對(dui)太(tai)(tai)陽(yang)(yang)能(neng)側發(fa)(fa)(fa)(fa)電(dian)量(liang)的(de)影響;另一方面由于耦合(he)了太(tai)(tai)陽(yang)(yang)能(neng),可以有效(xiao)(xiao)(xiao)減少傳(chuan)統(tong)化石(shi)能(neng)源發(fa)(fa)(fa)(fa)電(dian)系統(tong)的(de)消耗并(bing)改善環境問題,也有效(xiao)(xiao)(xiao)解決了太(tai)(tai)陽(yang)(yang)能(neng)利用不穩定和發(fa)(fa)(fa)(fa)電(dian)成本高(gao)等問題。因此,太(tai)(tai)陽(yang)(yang)能(neng)與化石(shi)燃(ran)料(liao)互(hu)補發(fa)(fa)(fa)(fa)電(dian)系統(tong)是(shi)目前(qian)解決太(tai)(tai)陽(yang)(yang)能(neng)高(gao)效(xiao)(xiao)(xiao)利用的(de)重點(dian)發(fa)(fa)(fa)(fa)展方向(xiang)。
圖:配置儲熱的太陽能-燃煤熱互補發電機組
太陽(yang)能(neng)熱(re)(re)(re)互補(bu)發(fa)(fa)電系(xi)(xi)統同樣需(xu)要搭配(pei)儲(chu)熱(re)(re)(re)。一(yi)方(fang)面(mian),儲(chu)熱(re)(re)(re)系(xi)(xi)統與太陽(yang)能(neng)-化(hua)石能(neng)源熱(re)(re)(re)互補(bu)系(xi)(xi)統相結(jie)合,可以提(ti)(ti)高(gao)(gao)(gao)太陽(yang)能(neng)利(li)(li)用率,進一(yi)步節(jie)省化(hua)石燃(ran)料消耗(hao)量,提(ti)(ti)高(gao)(gao)(gao)整個(ge)機組經(jing)濟性,另一(yi)方(fang)面(mian),熱(re)(re)(re)互補(bu)系(xi)(xi)統總運(yun)行(xing)時長(chang)將(jiang)大幅提(ti)(ti)高(gao)(gao)(gao),且可使太陽(yang)能(neng)側的(de)輸出保持穩定,有利(li)(li)于(yu)系(xi)(xi)統的(de)安全性和高(gao)(gao)(gao)效性。有科研(yan)人(ren)員對搭配(pei)儲(chu)熱(re)(re)(re)系(xi)(xi)統的(de)太陽(yang)能(neng)-燃(ran)煤熱(re)(re)(re)互補(bu)發(fa)(fa)電機組進行(xing)了建模計算,根據測算結(jie)果,一(yi)套(tao)660MW光熱(re)(re)(re)互補(bu)發(fa)(fa)電機組在(zai)搭配(pei)雙罐熔融鹽儲(chu)熱(re)(re)(re)系(xi)(xi)統后,最高(gao)(gao)(gao)可節(jie)約煤15.55%,提(ti)(ti)高(gao)(gao)(gao)系(xi)(xi)統熱(re)(re)(re)電效率3.3%。
搭配儲熱裝置的熱電聯產
熱(re)(re)(re)(re)電聯產是最早將(jiang)電源(yuan)(yuan)側儲熱(re)(re)(re)(re)投(tou)入(ru)實(shi)際(ji)生產的(de)領(ling)域。由于存在峰(feng)谷差,熱(re)(re)(re)(re)電聯產機(ji)(ji)組受供熱(re)(re)(re)(re)限(xian)制而(er)不(bu)能充分投(tou)入(ru)運(yun)行,導致熱(re)(re)(re)(re)電調度無(wu)法高效(xiao)運(yun)行,故(gu)機(ji)(ji)組調峰(feng)能力被“以熱(re)(re)(re)(re)定電”限(xian)制,將(jiang)熱(re)(re)(re)(re)電聯產技(ji)術與(yu)儲熱(re)(re)(re)(re)技(ji)術相結合(he),可(ke)(ke)以有效(xiao)降(jiang)低用能峰(feng)谷差,減少(shao)一(yi)次(ci)能源(yuan)(yuan)消(xiao)耗。此外,儲熱(re)(re)(re)(re)系(xi)統(tong)可(ke)(ke)以實(shi)現熱(re)(re)(re)(re)電聯產機(ji)(ji)組的(de)熱(re)(re)(re)(re)電解耦,提高了冬季取(qu)暖期(qi)的(de)調峰(feng)能力。目前,國內外的(de)熱(re)(re)(re)(re)電聯產機(ji)(ji)組已(yi)普遍使(shi)用以水蓄熱(re)(re)(re)(re)技(ji)術為主的(de)儲熱(re)(re)(re)(re)裝置。
圖:配置儲熱的熱電聯產機組
根據(ju)對我國(guo)目前(qian)在運(yun)的(de)北方熱(re)電聯(lian)產(chan)機組的(de)數(shu)據(ju)分析,配置儲熱(re)系(xi)統的(de)機組調峰能力均有大幅度提(ti)高。北方地區的(de)一(yi)臺300MW熱(re)電聯(lian)產(chan)機組,在配備儲熱(re)裝置后調峰容量(liang)從15.5%提(ti)升(sheng)至37%,最(zui)大電出力提(ti)升(sheng)了64.6MW。
電源側儲熱需擴大產業規模技術提升是關鍵
儲(chu)(chu)熱(re)(re)技(ji)(ji)術(shu)(shu)是具有廣闊發展前景的(de)節能(neng)技(ji)(ji)術(shu)(shu)。電(dian)力體制改革和(he)“雙碳”目標的(de)提出(chu)給能(neng)源(yuan)行(xing)業帶來(lai)了(le)新的(de)機遇(yu)和(he)挑戰,隨著新能(neng)源(yuan)裝機占比的(de)上升,電(dian)源(yuan)側(ce)調(diao)峰能(neng)力受到了(le)更高的(de)要求。儲(chu)(chu)熱(re)(re)技(ji)(ji)術(shu)(shu)在電(dian)源(yuan)側(ce)的(de)應用能(neng)做(zuo)到兼顧調(diao)峰和(he)能(neng)源(yuan)清潔(jie)(jie)化,是未(wei)來(lai)我國電(dian)力系(xi)(xi)統(tong)不可或缺的(de)組成部分(fen)。除了(le)上文提到的(de)光熱(re)(re)發電(dian)和(he)熱(re)(re)電(dian)聯產領域之外,電(dian)源(yuan)側(ce)儲(chu)(chu)熱(re)(re)技(ji)(ji)術(shu)(shu)還(huan)可應用于多能(neng)互補系(xi)(xi)統(tong)等其他(ta)新型能(neng)源(yuan)系(xi)(xi)統(tong),打(da)造(zao)全(quan)面、穩定(ding)、清潔(jie)(jie)的(de)綜合能(neng)源(yuan)服務(wu)。
另一方面,以光熱(re)(re)(re)(re)發電(dian)(dian)為主的(de)電(dian)(dian)源側儲(chu)(chu)熱(re)(re)(re)(re)技術(shu)(shu)裝機(ji)容量提升(sheng)緩慢,主要原因(yin)是受(shou)到現有技術(shu)(shu)的(de)限(xian)制。從儲(chu)(chu)熱(re)(re)(re)(re)介質而言(yan)(yan),需(xu)要尋(xun)找(zhao)兼顧儲(chu)(chu)熱(re)(re)(re)(re)溫(wen)度、儲(chu)(chu)熱(re)(re)(re)(re)密度和傳熱(re)(re)(re)(re)能(neng)力(li)的(de)優(you)質儲(chu)(chu)熱(re)(re)(re)(re)材料,從儲(chu)(chu)熱(re)(re)(re)(re)方式而言(yan)(yan),顯(xian)熱(re)(re)(re)(re)/潛熱(re)(re)(re)(re)混合儲(chu)(chu)熱(re)(re)(re)(re)能(neng)降低(di)(di)系(xi)統成(cheng)本、提升(sheng)熱(re)(re)(re)(re)效率,從儲(chu)(chu)熱(re)(re)(re)(re)系(xi)統設計(ji)(ji)而言(yan)(yan),優(you)化系(xi)統設計(ji)(ji)能(neng)大幅度降低(di)(di)成(cheng)本并提高系(xi)統安全(quan)性。因(yin)此,儲(chu)(chu)熱(re)(re)(re)(re)技術(shu)(shu)的(de)提升(sheng)是行業發展關(guan)鍵(jian),只有研發了更多新技術(shu)(shu),才能(neng)讓儲(chu)(chu)熱(re)(re)(re)(re)在電(dian)(dian)源側的(de)應用更加成(cheng)熟。