Ormat, Berkshire Hathaway say long duration problem can be solved by geothermal

For speakers at the Geothermal Resource Council's Policy Committee Panel, the future of geothermal lies in its ability to be a multi-purpose resource. 

Although geothermal is a resource not as common as wind or solar, experts say the potential is in its variability. As a resource, it can produce power, work in heat pump storage for full electrification, work as baseload power and be direct use, and it has a possible future in desalination for lithium production, which could make it more attractive going forward as states and utilities move to meet 100 percent renewable goals. 

"[Power is] going to a distributed thermal grid, and what we do with that thermal grid, the sky is the limit," said speaker Jay Egg, president of EGG Geothermal. "We’ve got heat pumps tied into them, some can be direct use."

"What sets geothermal apart from other technologies is that it’s really the combination of two efforts, especially on the electrification side, which is the subsurface drilling of the wells, combining of the geothermal resource...and then we have the power plant manufacturing and the sale of electricity and so forth," agreed panelist Jonathon Weisgall, vice president at Berkshire Hathaway Energy. 

Given geothermal's ability to provide constant energy, it can be attractive for those seeking baseload power, but geothermal developers frequently have trouble appealing to utilities due to the high cost, according to Weisgall. However, as states such as California seeks long-duration storage and more baseload power to prevent additional blackouts while transitioning to a fully renewable grid, geothermal could have an in. 

"The question is, what exactly is geothermal competing with?" Weisgall said. "To me, the competition is not wind and solar, to me the competition is batteries and pumped storage. Well, geothermal looks pretty attractive certainly when you compare it to batteries." 

Paul Thomsen, Vice President at Ormat Technologies, agrees, describing solar-plus-storage mitigation efforts as the "Costco effect." 

"When you hear a discussion for long-duration storage, it's a clarion call for more geothermal, because you’re trying to fix a problem that’s been created by intermittent resources and when you have too many intermittent resources you have to shift huge amounts of power to when you need it," Thomsen said. "I like to call this the Costco effect, you go into a Costco needing one stick of deodorant and come out with 50 of them. That’s kind of what intermittent resources is doing."

"Solar with integrated storage gets reduced the more geothermal you bring on..." he added. "We’ve beat solar with integrated storage today, we definitely beat it when you look at much bigger battery decks being put on." 

Weisgall noted that while geothermal doesn't have the flexibility that battery storage can offer, desalination might be able to change that. While the practice has still only been proven at 1/1000th commercial scale, he hopes desalination can reach commercial operation by 2027. 

"Let’s assume you use your geothermal plants for desalination, which needs a lot of electricity," Weisgall said. So from 9am until 4pm, you’re still generating your power but you’re using it at your plant or very locally for desalination. And then when the ramp up is needed for the duck curve...you come back on to the grid. That’s where geothermal can be flexible like long-duration."

Geothermal does have the ability to work with solar, using panels on the roof for electricity while using geothermal for heating, but panelists hoped that it could reach its potential as its own resource, as well. 

"You get everything when you buy a geothermal plant, you basically have a dispatchable full-time load that can be delivered," Thomsen said. "You don’t get that with solar, and you certainly don’t get that with wind."