The Transcontinental Aqueduct, spur 15: The Poppy Canyon Solar farm and pumped storage plant

One of the many problems facing solar farms is that they produce electricity only when the sun shines, which is less than half the time, so for the rest of the time electricity must be provided some other way. Historically peak power demands were provided by pumped storage plant, but very few have been built since the 70’s. Peak power is now supplied by natural gas electric plants, which is for now the most economic solution. If we want to get real about reducing our fossil fuel dependence, pumped storage must be looked at seriously, especially when changing our vehicle fleet from gasoline or diesel fuel to electric power source.

Here is spur 15 proposal sketch

Dam 1 is the Poppy Canyon Upper Lake. To fill this lake in a year requires Spur 15 to have a capacity of 330 cfs. It will require 240 GWh to fill the lake from the TCA connection point. It has a 4,000 feet wide and up to 640 feet high dam, topping out at 5400 feet, and the lake holds a volume of up to 240,000 acre-ft of water. It would normally hold a minimum volume of 60,000 acre-feet of water to increase the average height difference between the upper and lower dam.

Dam 2 dams the Cove Tank dam. It has a 3,300 feet wide and up to 360 feet high dam, topping out at 4,080 feet, and the lake holds a water volume of up to 110,000 acre-ft. Water is pumped from and released to the upper dam via a 13 mile tunnel

Dam 3 is the Poppy Canyon Lower Dam. It has a 3,300 feet wide and up to 460 feet high dam, topping out at 4,900 feet, and the lake holds a water volume of up to 70,000 acre-ft. Water is pumped from and released to the upper lake 1.8 mile tunnel.

How much energy will it generate per day? To dam 2 will be releasde 110,000 acre-ft for 5 hrs generating 115 GWh per day or 23 GW of peak power for 5 hrs. Dam 3 will release 70,000 acre-ft for 5 hrs generating 25 GWh per day or 5 GW of peak power for 5 hrs. To again fill dam 2 and 3 will require 17 GW of power from the solar panels. An alternate power would be 9 GW of LFTR power plants, generating 9 GW of alternate peak power when water is released. Most probably the power sources will be a combination of the two.

This pumped storage plant will add another 120% to the existing U.S. pumped storage capacity.