TECH

At Salton Sea, geothermal hopes persist

Sammy Roth
The Desert Sun

With the fate of the Salton Sea hanging in the balance, all eyes are turned toward the lake's southern shore. That's where 11 geothermal power plants churn out electricity 24 hours a day, seven days a week, with the potential for massively expanded energy development.

Local leaders see new geothermal development as critical to funding the restoration of the Salton Sea, which has been receding as agricultural runoff declines. Restoration is likely to cost between $3 billion and $9 billion, and the Imperial Irrigation District has estimated that geothermal development could generate $2 billion in royalty payments over the next 30 years.

But while the Salton Sea is home to one of the world's most potent geothermal reservoirs, developing that energy is expensive — at least compared to other renewable energy sources, including wind and solar. The result is that geothermal development by the lake has come to a standstill. Only one new plant has been built since 2000, and plans for additional facilities have either stalled or been scrapped.

Geothermal advocates had hoped that Senate Bill 1139 — a high-profile bill aimed at boosting development across California — would jumpstart geothermal activity by the sea. But while the state Senate approved it by a 21-11 margin in June, the bill failed to garner enough support to make it through the Assembly.

"It was a very aggressive bill. It got a lot of opposition," said state Sen. Ben Hueso, D-San Diego, the bill's author. "But it also made it very far down the line. I think that shows there's a lot of support in the state to advance geothermal as a resource."

Hueso isn't the only local leader who's hopeful despite the bill's failure. Geothermal advocates point to a host of factors they say bode well for future development by the Salton Sea, ranging from a little-known bill passed by the state Legislature last month to the potential for extracting lithium and other valuable minerals from geothermal brine.

They also point to the development of hydraulic fracturing technology that could be used to harness geothermal energy previously thought to be unreachable. But according to Randy Keller — director of development for CalEnergy, which owns 10 of the 11 plants by the Salton Sea — traditional technology is more than good enough to tap the enormous quantities of energy lying in wait near the sea.

"The Salton Sea resource is one of the hottest resources in the world — definitely in North America, but arguably the world," Keller said. "Why would we try a different system when we're sitting on the golden goose?"

'The golden goose'

If fully developed, the Salton Sea Known Geothermal Resource Area — an underground reservoir covering more than 100,000 acres — could transform the country's geothermal landscape. The reservoir's salty water and naturally occurring heat make for a geothermal hotspot, with temperatures above 500 degrees Fahrenheit creating steam that can be used to turn turbines and create electricity.

While geothermal has a long history in the United States — the first plant opened in 1971 — it's still a relatively small, and largely regional, industry. According to the federal Energy Information Administration, the vast majority of the country's 66 geothermal plants with at least one megawatt of capacity are in the Southwest, and more than four-fifths of total generating capacity comes from California alone. Within California, more than three-quarters of generation comes from two counties: Imperial, home to the Salton Sea resource area, and Sonoma, home to the world's largest geothermal field, the Geysers.

The 11 plants by the Salton Sea generate about 400 megawatts of electricity, and researchers have estimated that an additional 2,000 megawatts could be available — partly because more goethermal hotspots are likely to become accessible as the sea recedes. By comparison, there are currently only 3,700 megawatts of generation nationwide.

"I see a bright future with geothermal. I do," Hueso said. "I don't see it necessarily in the next three years, but in the next 10 years, we're going to see geothermal investment increase."

Many of the country's first geothermal plants were built in California in the 1970s and 1980s, with widespread development continuing by the Salton Sea, at the Geysers and elsewhere into the 1990s. But of the 32 plants with at least one megawatt of capacity that have been built since 2001, only seven are in California.

Energy Information Administration analyst Fred Mayes said that development has slowed in California because most of the state's easily accessible geothermal hotspots are already producing electricity. In a briefing on the topic last week, Mayes wrote that even though California has the country's greatest geothermal potential, recent plants "have increasingly been located in other western states as most of the low-cost resources in California have already been developed."

That economic reality has been a source of frustration for geothermal advocates, especially as solar development has taken off. While California's solar generating capacity increased fivefold from 2011 to 2013, its geothermal capacity barely budged, increasing 3 percent.

EnergySource, which opened the 11th geothermal plant by the Salton Sea in 2012, scrapped plans for a second facility earlier this year when unsatisfactory drilling results indicated the plant would not be economically viable. CalEnergy has been sitting on a permit for a massive new Salton Sea plant for four years, but it hasn't been able to secure a power purchase agreement with a utility — a key step before construction can begin.

"Geothermal is just not the favorite renewable technology that the utilities have procured," Keller said.

Competing renewables

California's renewables portfolio standard (RPS) is the nation's most stringent renewable energy mandate, requiring utilities to buy 33 percent of their power from renewable sources by 2020. The California Public Utilities Commission has instructed utilities to sign contracts for renewable energy using a "least-cost, best-fit" standard, which prioritizes minimizing the cost to electricity consumers while still meeting the RPS goals.

The state's three major investor-owned utilities — Southern California Edison, Pacific Gas & Electric and San Diego Gas & Electric — are already close to meeting those goals, and they've done so largely without geothermal energy. Based on contracts it has already signed, Edison projects that by 2020, it will buy 23.5 percent of its electricity from renewable sources — with just 3.3 percent of its overall energy mix coming from geothermal.

Pacific Gas & Electric, meanwhile, projects it will buy 31.3 percent of its electricity from renewable sources by 2020, with just 3.2 percent of its overall supply coming from geothermal. San Diego Gas & Electric projects its electricity will be 38.8 percent renewable by 2020, with none of its energy coming from geothermal.

While there's no denying that the high costs of building and operating a geothermal plant have made geothermal less competitive than wind and solar, the industry insists that regulators and utilities have ignored its main advantage over other renewables: that it is a "baseload" power source. This means that unlike wind and solar photovoltaic facilities — which only provide electricity when the wind is blowing or the sun is shining — geothermal plants can produce power at all hours of the day and night.

In California, intermittent solar and wind generation has increasingly been supplemented by natural gas-fired power plants, which emit far less carbon than traditional coal-fired plants. But as the state moves away from carbon-emitting energy sources altogether, Gawell said, the need for geothermal will grow.

"Geothermal's advantage has always been that it's a baseload power resource, so you can directly replace gas, or coal, or nuclear power, without having to bring in another resource," Gawell said.

Carl Zichella, director of western transmission for the Natural Resources Defense Council's Energy Program, said geothermal provides "a tool that you can turn on right when you need it." In California, he noted, peak energy use occurs in the evening, right as the sun is going down.

"That's really the time when we're losing thousands of megawatts of solar energy in a very short period of time," Zichella said. "That's when a resource like geothermal can be most valuable — to ramp up when we need it, when we predictably know that we're going to need it every day."

Still, not all geothermal plants can be turned on and off so easily, because cutting production too dramatically can cause a well to stop flowing, leading to a time-consuming reactivation process. Alexander Schriener, director of geothermal resources for CalEnergy, said the company's plants by the Salton Sea aren't designed to ramp up and down, but rather to provide energy around the clock.

While geothermal advocates argue that the state needs more baseload power — particularly in light of the San Onofre nuclear plant's permanent closure — others aren't convinced.

"Baseload geothermal is a costly way to meet our clean-energy goals, and it's inflexible. It's 24/7," said Nancy Rader, executive director of the California Wind Energy Association. "They say they can operate flexibly, but that would come at a pretty high price."

Changing the conversation

SB 1139 promised to jump-start California's stagnant geothermal industry. The bill — which was sponsored by Hueso and Assemblyman V. Manuel Pérez, D-Coachella — would have required utilities to buy 500 megawatts of electricity from new geothermal plants by 2024, likely leading to significant new development by the Salton Sea.

But SB 1139 proved controversial, with utilities saying it would drive up electricity rates and solar and wind advocates saying it created an unfair carve-out for geothermal. While the geothermal industry contends that wind and solar have their own carve-outs, there was ultimately enough opposition to the bill that Hueso and Pérez didn't bring it to the floor of the Assembly, likely knowing it wouldn't pass.

"The political process was really stacked against it. I think every regulatory agency and every other utility in the state was basically opposing 1139, because they generally oppose a carve-out," said Carl Stills, energy manager for the Imperial Irrigation District, which supported the bill. "Nobody wants to be told what to do, except that we have carve-outs all the time."

But Stills and other geothermal advocates are undaunted. Even though the bill failed, they argue, it brought attention to geothermal's potential.

"1139 did one thing that the geothermal industry hasn't had in a long time — it brought the geothermal industry and the Salton Sea to the forefront of the conversation," Stills said. "What we found was that in Sacramento, everyone was talking about geothermal again. And they weren't before 1139."

Hueso has been trying to capitalize on that momentum, meeting Wednesday with representatives from Gov. Jerry Brown's office and several state agencies to discuss non-legislative actions that could bolster the state's geothermal industry. One of the actions they discussed, Hueso said, was encouraging the federal government and the state's Department of Water Resources to procure more geothermal energy.

"It just doesn't make sense that a lot of our state and federal agencies are procuring power from coal, when we can really make a statement to our community about supporting renewables," he said.

Hueso didn't rule out introducing another geothermal bill in the Legislature. He noted that on the last day of this year's session, he found out that legislative leaders had struck a deal with the major utilities, in which the utilities agreed to support a bill requiring 250 megawatts of geothermal procurement, in exchange for some concessions.

While there wasn't time to modify the bill to reflect that deal, the fact that the utilities were willing to accept a smaller carve-out, Hueso said, gave him hope that a future bill could pass. Still, he believes administrative actions are more likely to succeed.

"We're not really looking at the path of least resistance — we're looking at the path of most certainty," he said. "We want to achieve our goal. Our goal is to build more geothermal in our state, and right now we're looking at how to accomplish that."

True costs

While SB 1139 was mired in controversy, another bill seen by the geothermal industry as potentially game-changing sailed through the Legislature with relative ease. That legislation — Assembly Bill 2363 — was unanimously approved by both houses last month, with no opposition from the wind or solar industries.

The California Public Utilities Commission (PUC), which oversees the state's renewable energy mandate, currently prohibits utilities from considering the "integration costs" of a power source when deciding where to buy renewable energy. While the term "integration costs" is shrouded in ambiguity, it usually refers to the costs of bringing intermittent power sources like wind and solar onto the grid — the cost, for instance, of ramping up a natural gas plant to meet demand when the sun goes down, or of building and maintaining transmission lines that are only used when a wind or solar plant is producing power.

Geothermal advocates see the PUC's prohibition on considering integration costs as fundamentally unfair, because it means that wind and solar plants are not penalized for their intermittent nature. Southern California Edison has also argued in filings with the commission that it should be allowed to consider integration costs, but the commission has been slow to address the issue.

That should change with the passage of AB 2363, which requires the PUC to establish a method for calculating integration costs by the end of 2015. Citing estimates calculated by the consulting firm Energy + Environmental Economics, Gawell said that once integration costs are taken into account, geothermal goes from "being one of the higher-cost (renewables), to being competitive with everything else."

"It's not like integration is going to clean the tables, but it's going to give us more of a fighting chance when everything is considered," Gawell said.

CalEnergy's Keller agreed, saying that integration costs "will help a great deal."

"It will put us all on a level playing field with the intermittent technology," he said. "We do see the market turning around, and that's why we're still staying involved."

'We're the little guy'

Advocates for wind and solar, though, are skeptical that integration costs will tip the balance toward geothermal, which helps explain why none of the wind and solar associations opposed the final version of AB 2363.

Shannon Eddy — executive director of the Large-scale Solar Association, a Sacramento-based trade group — said she doesn't expect integration costs to be a serious obstacle for the solar industry in California. Her organization originally opposed AB 2363, but it changed its position after the bill's language was changed to give the PUC more flexibility in calculating integration costs.

"We're very supportive of the development of the integration adder, but it's a very technical and challenging issue for legislators to work through," said Rachel Gold, the Large-scale Solar Association's policy director.

Rader, from the California Wind Energy Association (CalWEA), believes that even with integration costs taken into account, wind will continue to out-compete geothermal.

"People are assuming that the figures are going to be large enough to tip the scales between the technologies," she said. "We've now become a strong advocate of getting the figures updated, so that people don't make the assumption that the numbers are going to be large."

Rader questioned why none of the geothermal trade groups has submitted a proposal to the PUC for how integration costs should be calculated, noting that CalWEA is the only group that's done so. Gawell called those comments "offensive," firing back that CalWEA has twice as many paid staffers as the Geothermal Energy Association.

"What it says is if you don't have enough lobbyists, you shouldn't be counted," he said.

"We're an organization with very limited resources, and to hire a consultant to do a major study is a very major piece of work," he added. "We as an industry association—we're the little guy."

State Assemblyman Brian Dahle, R-Bieber, who wrote AB 2363, said even he doesn't know how big a difference the bill will make. What's important, he said, is to ensure that geothermal and other baseload renewables are getting a fair shake.

"Maybe wind and solar will come out ahead, but at least we'll know," he said. "I think it will help the biomass and geothermal people to compete."

'A lot of money to be made'

While AB 2363's impacts won't be fully understood for several years, geothermal advocates believe that two emerging technologies will make the industry more economically competitive. One of those technologies is being developed at the Salton Sea geothermal field: the ability to extract lithium and other valuable minerals from geothermal brine, a by-product of geothermal energy generation.

While the idea of extracting minerals from geothermal brine is not new, past efforts at the Salton Sea have failed to become economically viable. But Simbol Materials, a Pleasanton-based company founded in 2006, has developed an innovative process that it says will make the extraction of high-quality minerals financially feasible — and more environmentally sustainable. Simbol has spent several years testing that process at its demonstration plant in Calipatria, using brine from EnergySource's Featherstone plant, and it is now finalizing designs for a large-scale facility.

Lithium is a key ingredient in the batteries used by many electric automakers, and the Salton Sea area's geothermal brine could be one of the world's best sources of that lithium. If Simbol can show that its extraction process is commercially viable, the company could remake international lithium markets and bring a flood of battery manufacturers to the Imperial Valley — including Tesla, which plans to build several battery factories in addition to the one it has planned for Nevada.

Mineral extraction could also change the economics of geothermal energy development, by giving companies like CalEnergy and EnergySource a new revenue stream. Simbol pays EnergySource a fee for the use of its geothermal brine.

The average 50-megawatt geothermal facility in Imperial County, Stills said, makes about $44 million per year selling its electricity. The extraction of just four minerals, he said — lithium, potassium, zinc and possibly rubidium — could generate between $400 million and $600 million per year, although those numbers are highly speculative.

"There's a lot of money to be made in this geothermal field down here," Stills said.

Simbol's technology could also bring down geothermal plants' maintenance costs, by removing minerals that clog the pipes used to re-inject geothermal brine into the ground. Simbol's vice president of business development, Tracy Sizemore, said in a recent interview that the company could save EnergySource $10 million over 10 years.

Fracking for heat

Hydraulic fracturing technology could also make geothermal development more cost-effective. While "fracking" is traditionally associated with oil and gas drilling, the Department of Energy has funded research into how the technology could be used to access underground geothermal resources previously thought to be unreachable.

Mayes, from the Energy Information Administration, said the idea behind so-called "enhanced geothermal systems" is simple. While most geothermal plants have been built in locations where naturally heated water occurs close to the Earth's surface, it should be possible to access deeper geothermal hotspots by fracturing underground rock formations, creating a pathway for hot water to get to the surface.

Several enhanced geothermal demonstration projects are being funded by the Department of Energy, including two in California. The first commercially producing enhanced geothermal facility — which uses fracking technology to draw more energy from a conventional geothermal well — recently began operating in Nevada.

While companies have successfully tapped the Salton Sea geothermal field using traditional techniques, fracking could eventually open up much larger geothermal resources. Gawell believes that fracking "could transform geothermal entirely."

"We could be having a totally different discussion in five or 10 years," he said.

Geothermal fracking is not without its dangers, including the risk of creating earthquakes. A proposed enhanced geothermal project in Switzerland, which would have been located on a seismic fault, was never completed because it triggered earthquakes that caused serious damage to local infrastructure

But few of the concerns surrounding fracking for oil and gas — including the risk of drinking water contamination — have been raised about geothermal fracking, at least at this early stage. And experts say that the industry is taking strong steps to avoid the risk of strong earthquakes.

"Unlike oil and gas, the geothermal industry has a put a lot of thought into how they deal with that issue," said Briana Mordick, a staff scientist with the Natural Resources Defense Council's Land and Wildlife Program. "So far, most of the induced earthquake have been of a relatively small magnitude, smaller than what you'd feel at the surface."

Renewable infighting

Another source of optimism for geothermal advocates is the likelihood that California will require much more renewable energy — from all sources — in the coming years. Between the state's landmark climate change law, AB 32 — which requires it to reduce its greenhouse gas emissions to 1990 levels by 2020 — and the federal Environmental Protection Agency's proposed rule to reduce carbon emissions, there's little doubt that California's energy mix will need to far exceed 33 percent, sooner rather than later.

These policies and others, Mayes said, led the Energy Information Administration to project that geothermal generation in California will quadruple by 2040.

"You've got to have geothermal — which is a way of saying, if you wish, that geothermal is market competitive," Mayes said. "But when we say it quadruples, you have to look at the amount of capacity compared to other things. It's not very big."

It's not hard to see what Mayes is talking about. The agency projects California will have 10.3 gigawatts of wind capacity and 8.11 gigawatts of solar photovoltaic capacity by 2040, compared to just 5.44 gigawatts of geothermal capacity. Solar photovoltaic capacity is projected to grow at an average annual rate of 9.7 percent, compared to 4.6 percent for geothermal.

It's projections like those that lead to infighting in the renewable energy community, with solar, wind and geothermal trade groups and advocates squabbling for a greater share of the state's energy mix.

"You have to remember that solar and wind have a huge lobby. And what are they after? More solar and wind contracts," Stills said. "And the geothermal industry does a very poor job of selling themselves, although they're starting to change that."

With geothermal development at a standstill in Imperial County — where the unemployment rate is 24.7 percent — it's hard to blame local officials for pushing bills like SB 1139, which could create thousands of jobs by the Salton Sea.

"Geothermal is an investment in our own economy," Hueso said. "No source of energy creates more jobs per kilowatt hour than geothermal."

The Natural Resource Defense Council's Zichella believes that geothermal will need to be a more prominent piece of the country's renewable energy mix. But seeing renewable energy industries fighting among themselves, he said, "drives me crazy." The reality, he said, is that reducing greenhouse gas emissions while meeting the country's energy needs will necessitate more development of all renewables.

"What we often see, when you have industries that perceive themselves to be competing for a mix, is that they lose track of the big picture," Zichella said. "And the big picture is that they work better together."

The Salton Sea

Restoring the Salton Sea is a very different objective than reducing greenhouse gas emissions, but it's no less timely. The sea will start shrinking more quickly after 2017, when water deliveries will be reduced dramatically under the 2003 Quantification Settlement Agreement, the nation's largest agricultural-to-urban water transfer deal.

The sea's decline has sparked a host of environmental concerns, including wafting dust, loss of critical habitat for fish and birds, and ecosystems threatened by rising salinity. The Oakland-based Pacific Institute released a report last week warning that the sea's continued decline could cost Californians more than $29 billion, partly due to lower property tax values and higher health care costs for respiratory illnesses.

"One way or another, we're going to have to address the issue," Gawell said. "It's not going to go away. It's going to be staring everybody in the face."

Local leaders emphasize that geothermal development alone will not save the Salton Sea alone, with Hueso calling geothermal "one piece of the puzzle." And Schriener cautioned that estimates for potential revenue from additional generation are merely that — estimates, which are years from being borne out in reality.

"When I see people giving a lot of happy talk, I say, 'Dude — is it really going to do that?" Schriener said.

But Salton Sea advocates agree that any restoration plan needs to include money from geothermal — and they haven't been deterred by the failure of SB 1139.

"This is not a one-year effort. People have to understand that restoring the Salton Sea is going to be a long project that's going to take the next 10, 20, 30 years," Hueso said. "But they can rest assured that that sea is going to survive."

Energy Reporter Sammy Roth can be reached at Sammy.Roth@desertsun.com, (760) 778-4622 and @Sammy_Roth.

How does geothermal work?

Geothermal energy development takes advantage of naturally emanating heat from the Earth's core, which can heat rock formations and water near the planet's surface as high as 700 degrees Fahrenheit. Most of the United States' prime geothermal hotspots, where heated water is either close to the surface or emerging from the ground, are in the Southwest.

The geothermal reservoir by the Salton Sea is one of the world's largest and hottest, with briny water heated to temperatures greater than 500 degrees Fahrenheit about a mile below sea level. The brine is about three-quarters water and one-quarter solid, with minerals ranging from lithium to manganese making up the solid component.

To tap that geothermal resource, companies drill wells into the rocky reservoir, lessening the extreme underground pressure that has forced the superheated brine to stay in liquid form. After that pressure gradient is created, the brine "flashes" from a liquid to a gas, emerging from the wells as steam. That steam is funneled through a series of machines, where it is used to turn turbines and create electricity.

It's important to keep temperatures high throughout the process, or the brine will condense back into a liquid. But as temperature begin to drop, plant operators slowly decrease the pressure on the brine, to ensure that it keeps boiling and keeps turning turbines. Some of the brine's solid components are removed during the process.

By the end of the process, the remaining steam's pressure isn't high enough to keep turning turbines, and it's released into the atmosphere — hence the tall plumes of white steam emerging from geothermal plants. CalEnergy releases about 20 percent of its brine as steam, returning the other 80 percent to the reservoir through a series of injection wells.