A venerable energy storage technology is getting a new lease on life thanks to a smart redesign and a deal between the power industry and environmentalists.
“Pumped storage is getting a makeover. The sleeping giant is waking up for several reasons,” said Dan Reicher, principal investigator at Stanford University and former U.S. undersecretary of energy.
The stumbling block of hydropower has long been opposition from environmentalists, as hydropower has relied on dams that damage river ecosystems.
But pumped storage systems are now designed as closed-loop systems, away from waterways. When solar and wind generation is high, they pump water from a reservoir at low altitude to another at high altitude. When electricity is needed, water is returned to the lower reservoir, spinning turbines that generate electricity.
“I’ve been involved with investors in pumped storage for a long time,” said Jay Precourt, an investor, supporter of energy initiatives and founder of Stanford’s Precourt Institute for Energy.
“It’s a fantastic project commercially,” he says in a video released by Stanford this month. “In the past, the heist was environmentalists. There has been pushback in many states from the environmental community. I know an investor right now with deep pockets and a lot of experience who is dying to do projects in California.
There’s a lot less opposition to the closed-loop system, Reicher said, because they’re not built on rivers, they don’t need dams, and because environmentalists are “essentially putting their names on a document that says they’re going to give much stronger support.
This document is a 2020 joint statement of collaboration signed by American Rivers, the World Wide Fund for Nature, the Union of Concerned Scientists, and nine hydropower industry organizations. In addition to promoting closed-loop pumped storage, the agreement calls for the removal of dams “that no longer provide benefits to society, have safety issues that cannot be cost-effectively mitigated, or have negative environmental impacts that cannot be effectively addressed”.
It also calls for adding power generation to some dams that currently lack it. “It turns out that only three percent of American dams produce electricity,” Reicher said.
Still, older pumped storage projects provide 90% of the United States’ energy storage capacity, Reicher said: 22,000 megawatts or 550,000 megawatt hours. Many of these existing projects were built in the 1970s and 1980s to capture excess nuclear power at night. Now they often pump water upstream in the afternoon when solar power is at its peak.
“Pumped storage provides large amounts of long-term storage measured in days or weeks, with the capacity of individual plants typically measured in hundreds or thousands of megawatts,” Reicher said. “The largest current pumped storage project exceeds 3,000 megawatts and is a facility in the state of Virginia.”
The Bath County Pumped Storage Station in Virginia has been called “the largest battery in the world”. Dominion Energy claims to power 750,000 homes. Built in 1977, it draws water from a dammed river.
Fong Wan, senior vice president of Pacific Gas & Electric Company, said he loves pumped storage, but he wouldn’t put PG&E’s money behind it.
“The issue here is actually construction cost certainty,” Wan said. “This nation hasn’t, as far as I know, done a new pumped storage facility in a long time, and the way the business world works is if I were to sign up for a project – a big project of pumped storage – I think it’s at least $2000 per kilowatt which will put it into billions and billions I want to know cost certainty like you would if you were to buy a house but very little many sellers are willing to offer me a fixed price, and I cannot offer it to my regulators or to my customers whose cost structure is unknown.
“That’s the biggest problem.”
According to Reicher, utilities would not be asked to provide the money. Due to the urgency of energy storage to balance solar and wind – and the promised decline of environmental opposition – investors are ready to fund pumped storage projects, he said. .
“I think the difference may be – and time will tell – that we have a much bigger community of investors, with a lot more money, who are tackling a very big problem, and I think that they’re pretty confident that we have a technology that can work. It still has to be proven, we still have to show that you can get big stuff like this built.
The bipartisan Infrastructure Act provides $2.4 billion for pumped storage. Meanwhile, Stanford’s Woods Institute for the Environment, which brokered the 2020 agreement between environmentalists and industry, is working to streamline the federal permitting process for pumped storage projects.
“I’m relatively optimistic that some of these projects will get built,” Reicher said. “Not all 80 will do, not all 80,000 megawatts will, but I think a decent number will.”
Watch the energy storage discussion at Stanford, which also included The new iron-air battery from Form Energy and Antora Energy’s design for thermal energy storage: