Pumped-storage hydroelectricity: Difference between revisions

Pumped storage is by far the largest-capacity form of [[grid energy storage]] available, and, as of 2020, PSH accounts for around 95% of all active storage installations worldwide, with a total installed throughput capacity of over 181 [[Gigawatt|GW]] and a total installed storage capacity of over 1.6 [[TWh]].<ref>{{Cite web |date=8 July 2020 |title=DOE OE Global Energy Storage Database |url=https://www.sandia.gov/ess-ssl/global-energy-storage-database-home/ |url-status=live |archive-url=https://web.archive.org/web/20210709184735/https://www.sandia.gov/ess-ssl/global-energy-storage-database-home/ |archive-date=9 July 2021 |access-date=12 July 2020 |website=U.S. Department of Energy Energy Storage Systems Program |publisher=[[Sandia National Laboratories]]}}</ref>

 

[[File:Pumpspeicherkraftwerk engl.png|thumb|Power distribution, over a day, of a pumped-storage hydroelectricity facility. Green represents power consumed in pumping. Red is power generated.]]

 

In micro-PSH applications, a group of pumps and [[Pump As Turbine]] (PAT) could be implemented respectively for pumping and generating phases.<ref name=":1a">{{Cite journal |last1=Morabito |first1=Alessandro |title=Pump as turbine applied to micro energy storage and smart water grids: A case study |last2=Hendrick |first2=Patrick |date=2019-10-07 |journal=Applied Energy |volume=241 |pages=567–579 |doi=10.1016/j.apenergy.2019.03.018 |s2cid=117172774 |doi-access=|bibcode=2019ApEn..241..567M }}</ref> The same pump could be used in both modes by changing rotational direction and speed:<ref name=":1a" /> the operation point in pumping usually differs from the operation point in PAT mode.

 

In closed-loop systems, pure pumped-storage plants store water in an upper reservoir with no natural inflows, while pump-back plants utilize a combination of pumped storage and conventional [[Hydroelectricity|hydroelectric plants]] with an upper reservoir that is replenished in part by natural inflows from a stream or river. Plants that do not use pumped storage are referred to as conventional hydroelectric plants; conventional hydroelectric plants that have significant storage capacity may be able to play a similar role in the [[Electric power transmission|electrical grid]] as pumped storage if appropriately equipped.

 

Taking into account conversion losses and evaporation losses from the exposed water surface, [[energy recovery]] of 70–80% or more can be achieved.<ref name="EconomistPSH">{{Cite news |date=2011-03-03 |title=Energy storage - Packing some power |newspaper=[[The Economist]] |url=http://www.economist.com/node/21548495?frsc=dg%7Ca |url-status=live |access-date=2012-03-11 |archive-url=https://web.archive.org/web/20200306081719/https://www.economist.com/technology-quarterly/2012/03/03/packing-some-power |archive-date=6 March 2020}}</ref><ref name="thier">{{Cite web |last=Jacob |first=Thierry |date=2011-07-07 |title=Pumped storage in Switzerland - an outlook beyond 2000 |url=http://www.stucky.ch/en/contenu/pdf/Pumped_storage_in_Switzerland_Dr_Jacob.pdf |access-date=2012-02-13 |website=Stucky|archive-url=https://web.archive.org/web/20110707003324/http://www.stucky.ch/en/contenu/pdf/Pumped_storage_in_Switzerland_Dr_Jacob.pdf |archive-date=7 July 2011 }}</ref><ref name="Levine">{{Cite web |last=Levine |first=Jonah G. |date=December 2007 |title=Pumped Hydroelectric Energy Storage and Spatial Diversity of Wind Resources as Methods of Improving Utilization of Renewable Energy Sources |url=http://www.colorado.edu/engineering/energystorage/files/MSThesis_JGLevine_final.pdf |publisher=University of Colorado |page=6|archive-url=https://web.archive.org/web/20140801113053/http://www.colorado.edu/engineering/energystorage/files/MSThesis_JGLevine_final.pdf |archive-date=1 August 2014 }}</ref><ref name="yang">{{Cite book |last=Yang |first=Chi-Jen |url=https://books.google.com/books?id=TPReBwAAQBAJ&dq=info:1fSw0yVikpMJ:scholar.google.com&pg=PA25 |title=Pumped Hydroelectric Storage |date=11 April 2016 |publisher=Duke University|isbn=9780128034491 }}</ref><ref name="ESA">{{Cite web |title=Pumped Hydroelectric Storage {{!}} Energy Storage Association |url=http://energystorage.org/energy-storage/technologies/pumped-hydroelectric-storage/ |archive-url=https://web.archive.org/web/20190119150459/http://energystorage.org/energy-storage/technologies/pumped-hydroelectric-storage/ |archive-date=19 January 2019 |access-date=15 January 2017 |website=energystorage.org}}</ref> This technique is currently the most cost-effective means of storing large amounts of electrical energy, but capital costs and the necessity of appropriate geography are critical decision factors in selecting pumped-storage plant sites.

 

====Small-scale facilities====

Smaller pumped storage plants cannot achieve the same [[economies of scale]] as larger ones, but some do exist, including a recent 13&nbsp;MW project in Germany. Shell Energy has proposed a 5&nbsp;MW project in Washington State. Some have proposed small pumped storage plants in buildings, although these are not yet economical.<ref name=":0">{{Cite journal |last1=de Oliveira e Silva |first1=Guilherme |title=Pumped hydro energy storage in buildings |last2=Hendrick |first2=Patrick |date=2016-10-01 |journal=Applied Energy |volume=179 |pages=1242–1250 |doi=10.1016/j.apenergy.2016.07.046|bibcode=2016ApEn..179.1242D }}</ref> Also, it is difficult to fit large reservoirs into the urban landscape (and the fluctuating water level may make them unsuitable for recreational use).<ref name=":0" /> Nevertheless, some authors defend the technological simplicity and security of water supply as important [[Externality|externalities]].<ref name=":0" />

 

== History ==