Helms Pumped Storage Plant

{{Infobox dam

| name = Helms Pumped Storage Plant

| name_official =

| image = Courtright Reservoir 2.jpg

| image_caption = Courtright, the upper reservoir

| image_alt =

| coordinates = {{coord|37|02|13|N|118|57|53|W|type:landmark|display=inline,title}}

| country = United States

| location = Fresno County

| status = O

| construction_began = 1977

| opening = 1984

| demolished =

| cost =

| owner = Pacific Gas and Electric Company

| operator =

| res_name = Courtright Reservoir

| res_capacity_total = {{Convert|123000|acre.ft|m3|0|abbr=on}}

| lower_res_name = Wishon Reservoir

| lower_res_capacity_total = {{Convert|129000|acre.ft|m3|0|abbr=on}}

| plant_pumpgenerators =

| plant_turbines = 3 x 404 MW Francis pump turbines

| plant_pumps =

| plant_hydraulic_head = {{Convert|1625|ft|m|0|abbr=on}}

| plant_capacity = 1,212 MW

| plant_capacity_factor =

| website =

| extra =

}}

The Helms Pumped Storage Plant is located 50 mi (80 km) east of Fresno, California in the Sierra Nevada Mountain Range's Sierra National Forest. It is a power station that uses Helms Creek canyon on the North Fork of the Kings River for off-river water storage[http://www.lmvp.org/Waterline/winter2003/dam.htm The Dam Truth About Reservoirs] "There are 2 broad categories of reservoirs, the valley reservoir [or on-river storage,] and the off-river storage reservoir" and the pumped-storage hydroelectric method to generate electricity. After being planned in the early 1970s, construction on the plant began in June 1977 and commercial operations began on 30 June 1984. It has an installed capacity of 1,212 MW and is owned by Pacific Gas and Electric Company.{{cite web|title=By the Numbers: Helms Pumped Storage Facility|url=http://www.pgecurrents.com/2011/10/17/by-the-numbers-helms-pumped-storage-facility/|publisher=Pacific Gas and Electric Company|access-date=15 January 2012|date=17 October 2011|archive-date=10 October 2014|archive-url=https://web.archive.org/web/20141010203547/http://www.pgecurrents.com/2011/10/17/by-the-numbers-helms-pumped-storage-facility/|url-status=dead}}

Design and operation

The power plant operates by moving water between an upper and lower reservoir. When energy demand is high, water is released from the upper reservoir to the generating plant and the water is discharged into the lower reservoir. When demand is low (such as at night), water is pumped into the upper reservoir to be used as stored energy at a later time. This is accomplished by pump-generators which serve a dual role: the pumps can reverse for use as generators. The plant can go from a stand still to operational in eight minutes which allows it to meet peak energy demand. It consumes more electricity pumping than generating electricity but pumping occurs during periods of low demand with unused surplus energy available at lower costs from the electric grid.{{cite journal|last=Kermit Jr.|first=Paul|title=Design Features of The Helms Pumped Storage Project|journal=IEEE Transactions on Energy Conversion|date=March 1989|volume=4|issue=1|pages=24–25|publisher=Institute of Electrical and Electronics Engineers|doi=10.1109/MPER.1989.4310531|bibcode=1989ITEnC...4....9P}}{{cite web|last=Yeung|first=Manho|title=Helms Pumped Storage Plant|url=http://www.nwcouncil.org/energy/wind/meetings/2008/10/ManhoYeung.pdf|publisher=Pacific Gas and Electric Company|access-date=15 January 2012|date=17 October 2008|archive-url=https://web.archive.org/web/20120102061650/http://www.nwcouncil.org/energy/Wind/meetings/2008/10/ManhoYeung.pdf|archive-date=2 January 2012|url-status=dead}}

The upper reservoir, Courtright Reservoir, has a storage capacity of {{Convert|123000|acre.ft|m3|0|abbr=on}} is at altitude of {{Convert|8184|ft|m|0|abbr=on}}. Wishon Reservoir, the lower reservoir, has a storage capacity of {{Convert|129000|acre.ft|m3|0|abbr=on}}. It is at an altitude of {{Convert|6550|ft|m|0|abbr=on}}. Connecting the reservoirs, from upper to lower, is first a {{Convert|10511|ft|m|0|abbr=on}} long head-race tunnel which turns into a {{Convert|2248|ft|m|0|abbr=on}} long steel penstock which drops in elevation and splits into three individual penstocks, which each feed a separate pump-generator. After the water has passed through the generating turbines, it is discharged into the lower reservoir via a {{Convert|3797|ft|m|0|abbr=on}} long tail-race tunnel. The difference in elevation between the reservoirs has an effective hydraulic head (drop of the water) of {{Convert|1625|ft|m|0|abbr=on}}. The underground power station is near Wishon Reservoir and houses three 404 MW Francis pump turbine-generators.

The Helms Pumped Storage project was designed to be used with the Diablo Canyon Nuclear Power Plant, also owned by PG&E, in the 1970s, when Diablo Canyon was being designed and permitted. It is connected to that power plant by a dedicated high-tension power line. [https://www.sanluisobispo.com/news/local/news-columns-blogs/photos-from-the-vault/article39098913.html "Diablo Canyon's odd cousin in the mountains"], October 12, 2015, San Luis Obispo Tribune

See also

{{stack|{{Portal|California|Water|Renewable energy}}}}

References

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