An Oklahoma generation and transmission cooperative will use a power purchase agreement to add 500 megawatts of renewable capacity to its system, and the deal backs up that power with a major investment in battery storage, creating the largest combined wind, solar and energy storage project in the nation.
Western Farmers Electric Cooperative announced the agreement with NextEra Energy in late July, with plans to have all the elements in place within five years.
“With the price of wind and solar energy lower than ever, we are now able to pair it with battery storage to make more affordable, renewable energy available,” said Gary Roulet, CEO of Anadarko-based WFEC.
The Skeleton Creek systems will be deployed across more than 30,000 acres located in three counties in north-central Oklahoma.
Plans call for 250 MW of wind generation to be operational by year’s end. Solar arrays totaling 250 MW of capacity should be fully operational by 2023. Four hours of battery storage capacity rated at 200 MW (800 MWh) will also be fully commissioned that year.
“Solar obviously generates power during the day and, in our area, wind typically generates power at nighttime. So, they actually complement each other very well,” said Phil Schaeffer, WFEC’s principal resource planning engineer. “Battery storage should smooth out the variability even more. When you have excess generation and not much load, you can actually store that energy.”
The combined wind, solar and battery storage project is the first of its kind tied to the Southwest Power Pool (SPP), which oversees the bulk electricity grid and wholesale power market for the central United States.
“With the large amount of wind the Southwest Power Pool has in its territory, it’s fairly hard on some days of high production to manage all of that wind generation,” said Schaeffer. “Battery storage will help with all of that excess generation at times. It ramps up instantly and there’s no other power generation technology that has this type of capability. It really puts a new tool in their tool bag.”
The three-phase project, once fully operational, will help WFEC achieve about 50% of its nameplate capacity with wind, solar and hydroelectric power. Solar generation will account for 521 MW of supply, and wind generation will top 955 MW. G&T officials have cited competitive costs and successful deployments of the technology as factors contributing to the timing of the agreements.
Under the terms of the power purchase agreement, NextEra Energy is negotiating all land leases and easement agreements and will build and maintain the systems.
“With this combined facility, we can optimize and maximize the amount of low-cost, emissions-free electricity we provide, while helping Western Farmers diversify its power generation portfolio,” said John Ketchum, president and CEO of NextEra Energy Resources.
Derrill Holly is a staff writer at NRECA.