Using air reduces overhead and materials costs compared with hydrogen storage.
Compressed air is stored during surplus times and fed back during peak usage.
Two new compressed air storage plants will soon rival the world’s largest non-hydroelectric facilities and hold up to 10 gigawatt hours of energy. But what is advanced compressed air energy storage (A-CAES), exactly, and why is the method about to have a moment?
Compressed air is part of a growingly familiar kind of energy storage: grid-stabilizing batteries. Like Elon Musk’s battery farm in Australia and other energy overflow storage facilities, the goal of a compressed air facility is to take extra energy from times of surplus and feed it back into the grid during peak usage.
Here’s how the A-CAES technology works: Extra energy from the grid runs an air compressor, and the compressed air is stored in the plant. Later, when energy is needed, the compressed air then runs a power-generating turbine. The facility also stores heat from the air to help smooth the turbine process later on.
While the efficiency of similar systems has hovered around 40 to 50 percent, the new system from Hydrostor, a major global leader in building hydroelectric storage, reportedly reaches 60 percent, according to Quartz.
Hydostor will store compressed air in a reservoir that’s partly filled with water to balance out the pressure. The whole system will hold up to 12 hours of energy for the grids where the two plants are planned. (The first plant will be built in Rosamond, California, while the second location is to be determined.)
Why branch out from hydrogen to compressed air? While hydro storage is a great part of the global energy scene, storing massive amounts of water requires a ton of infrastructure that Hydrostor says uses a lot of energy it’s ultimately trying to save. That makes intuitive sense if you think about the relative force of water compared with even heavily pressurized air.
“Pumped hydro accounts for around 95 percent of the world’s grid energy storage and gigawatt-capacity plants have been in operation since the 1980s. The problem is that you need a specific type of location and a staggering amount of concrete to build a pumped hydro plant, which works against the goal of reaching net zero. Rotting vegetation trapped in dams also contributes to greenhouse gas emissions. Meanwhile, the biggest mega-batteries built so far are only in the 200 MW/MWh range, though installations bigger than 1 GW are planned.
Recharge reports that companies have built smaller existing CAES facilities over naturally occurring salt caverns. In contrast, Hydrostor will be digging new caverns to use for its larger facilities in California, just as engineers are constructing huge salt caves in Utah to store hydrogen.
The first of Hydrostor’s two plants is set to open in 2026, and the company says its system will last for about 50 years—making it a lot longer-lived than almost any energy storage of its kind. The near future of energy is likely made of a dozen different solutions that are all suited to different environments and situations, so adding compressed air to the portfolio simply makes sense.
If you watched the Super Bowl, or even if you didn’t, you might well have seen the General Motors ad that features Will Ferrell pitching GM’s electric vehicles. It opens with Ferrell explaining that “Norway sells way more electric cars per capita than the U.S.” He then declares, “Well, I won’t stand for it,” before punching a globe and claiming that, with GM’s new electric battery, “we’re going to crush those lugers. CRUSH THEM! Let’s go, America.”
Ferrell, aka America’s loveable oaf, goes on to recruit Saturday Night Live’s Kenan Thompson and actress/comedian/celebrity Awkwafina to meet him in Norway, with him driving an electric Cadillac and them an electric Hummer to somehow get there. He actually ends up in Sweden and his two pals in Finland. But that’s beside the point.
Because the point’s been made: America will lead the world in EV use.
The ad doubles down on GM’s recent commitment to stop manufacturing gasoline and diesel vehicles by 2035. As this Atlantic article explains, that’s quite the about-face for the car company, given how it advocated for two regressive Trump administration positions: a rollback of anti-pollution rules and an attempt to block California’s regulation of vehicle emissions. Indeed, GM has been quite the laggard in this regard, as Ford and other automobile manufacturers opposed the administration on both issues.
Given how two-faced GM has been, we can’t be certain it will deliver on its promise until it’s further down the line. Still, the change itself couples with the company’s very public declaration of the move – you can’t get more public than a Super Bowl commercial – to reflect a decisive shift in the right direction for GM and the automotive industry more generally.
And it makes so much sense, even above and beyond environmental repercussions. According to the Atlantic piece:
In the future, Americans’ mass adoption of electric vehicles will seem inevitable. After all, EVs cost less to run than gas-powered cars (because electricity is cheaper than gas); they require cheaper maintenance; they break less; they are quieter. For many types of drivers—daily commuters, for instance, or errands-around-towners—they are already preferable to gas-powered cars.
GM’s good news comes with a message that should curb our enthusiasm: Note that the vehicles it uses in the Super Bowl commercial are a Caddy and a Hummer. As environmental/energy expert Philip Warburg notes, “GM’s soon-to-be released electric vehicle flagship, the three-ton, 1,000-horsepower all-electric Hummer, stands as a warning that American auto manufacturers will not be abandoning their energy-wasteful giants, even as they move from internal combustion engines to electric power.”
Warburg goes on to caution that, even as the Biden Administration thankfully steers the United States toward an EV future, it must still focus on exhaust emissions from fossil fuel vehicles and on restraining vehicle size:
First, while the prospect of an all-electric vehicle fleet is alluring, we are decades away from achieving that goal. We therefore can’t afford to shrug our shoulders while most of our cars and trucks continue to rely on gasoline and diesel fuel.
Second, an electrified U.S. fleet dominated by oversized SUVs and pickups will consume substantially more energy than a leaner line of electric vehicles, making it much harder for clean electricity sources to edge out the gas and coal plants that still supply most of our electricity.
However affable a face Ferrell puts on GM’s shift, then, the government and public still need to force and pressure car companies to head in the right direction.
Though this ad will never win any awards for subtlety, it nevertheless plays up the unwittingly Ugly American in a creative and positive way. Ferrell’s taking umbrage at the idea that Norway (!!!) is beating America in EV usage is really a knock at the notion of any country besting us in this regard.
What’s significant here is that GM is making EV progress a matter of pride and patriotism. The commercial plays a bit on our national ignorance by bringing together the mindless “We’re Number One!” notion with Ferrell’s globe-piercing display and his little group arriving not in Norway but neighboring nations.
But hey, if a good-natured but cluelessly competitive American stereotype serves a good cause by highlighting how we must catch up with other countries, I’m all for it. At least in this instance, the Ugly American is a beautiful thing to behold.
[Hat tip: MS]
Benicia resident Stephen Golub offers excellent perspective on his blog, A Promised Land: Politics. Policy. America as a Developing Country.
To access his other posts or subscribe, please go to his blog site, A Promised Land.
BENICIA CA – The arguments for and against a proposed Lake Herman Road Solar Project are persuasive. The good and the bad have caused an unusual divide, if not an ugly one.
Actually, the debate has been civil and constructive.
It all comes to a head tomorrow. Benicia City Council will hear the case and take a vote at it’s virtual meeting Tuesday, July 7. Our Planning Commission denied the project in May, but that decision was appealed to the City Council by the project sponsor, Renewable Properties.
I’m writing to ask you to vote to approve the proposed 35 acre solar array on Lake Herman Road.
As you all know, climate change is a serious and growing threat to all people, so we all have a responsibility to help counter it. When people say “think globally, act locally” this is exactly the sort of action they are talking about. While no one wants to lose open space, obtaining enough clean energy for 1,700 Benicia households is a big step in the right direction.
My wife and I walked to the area in question. It is not useful for recreation. The livestock currently grazing there will still have access to 54 acres of the 89 acre parcel after the solar panels are installed. We were glad to see that the plans call for planting native trees and plants that will mostly screen the site from view. They also call for creating a pollinator plant meadow which will increase local biodiversity. Personally, I like seeing solar panels because I know the good they are doing.
It would be preferable to install solar panels on homes and businesses, over parking lots and even over roads. However – we are clearly not there yet, and we need to take action now. Waiting a year or two is not acceptable.
There is a concern that approval of this project will create an open door for other, less desirable, development in our designated open space areas ~ so I hope Council will take care to ensure that no such loopholes are created as you approve this important project.
I’d like the City to take a more proactive and visionary leadership approach to opportunities like this. For example, could the City identify asphalt-covered terrain, roofs in the Industrial Park, or other possible mixed-use sites where responsible companies like Renewable Properties could install solar arrays? Could the City actively facilitate partnerships between solar or wind energy providers and local businesses to encourage clean energy development?
For now, I feel that the imperative to address the climate crisis and lower our carbon footprint needs to take precedence over protecting this small parcel of open space.
Let’s not make the perfect be the enemy of the good.
Opposition, by Don Dean
I see that the Lake Herman solar project is on the agenda for next week’s City Council meeting. I haven’t changed my stance on the project; I still think it’s a good project in the wrong location, and that the Planning Commission did the right thing in denying it. I’m all for solar power and fighting climate change, and so is everybody I know. But that doesn’t mean that every solar project is a good one. There are three issues here.
The first issue is designated Open Space and how we value it–or we don’t. Notice I capitalized Open Space. This is an official City designation. The solar project is proposed on City-designated Open Space land. So it’s not just undeveloped land waiting for an acceptable use to come along; in this case it’s specifically designated in Benicia’s General Plan to remain open for agricultural or recreational uses. The State of California considers Open Space important enough that it mandates an Open Space element be included in each city’s General Plan. With the pandemic we’re all involved in, open space has become more important than ever for our exercise, recreation, and sanity. With options for travel limited now, I find I drive Lake Herman Road more than ever and appreciate the vistas more than ever.
Second, this is about more than just one project on Lake Herman Road. The proposed zoning change necessary for the project would apply to about 159 parcels (2,000+acres) spread throughout Benicia. There has been no real analysis of how many other solar facilities could be constructed or where those might occur. The City has relied on a study by the applicant that asserts the number of solar-developable parcels would be very small. But that analysis doesn’t seem to have been independently verified. If the City is serious about solar development in Open Space areas, let’s have a community discussion about how and where solar is appropriate rather than make the decision based on approving one project.
Third, this is an industrial-scale solar project. It will blanket 35 acres with wall-to-wall panels. It belongs in an industrial area. The Benicia Climate Action Plan calls for solar development at large parking lot sites belonging to Amports, Valero, and the City. As far as I know, no one has approached Amports or Valero about adding solar arrays to their property. Not only would this generate power, but it would reduce the heat island effect from acres of asphalt. Shouldn’t we be looking for solar in these already developed areas rather than converting our Open Space to industrial uses and building outside the Urban Growth Boundary? Isn’t planning about being proactive for the future and protecting our existing resources?
I understand the urgency some people feel about getting a major solar facility to combat climate change, but this issue of solar development versus Open Space is a false choice. I don’t see why we need to sacrifice one to gain the other. Bottom line—I think this is a good project in the wrong place. I don’t think the project should be approved.
You already have my letter to the Planning Commission that lays out some of the more technical points of the discussion. Feel free to share this email.
Instead, utilities and energy companies are continuing to invest heavily in carbon-polluting natural gas. An exclusive analysis by USA TODAY finds that across the United States there are as many as 177 natural gas power plants currently planned, under construction or announced. There are close to 2,000 now in service.
All that natural gas is “a ticking time bomb for our planet,” says Michael Brune, president of the Sierra Club. “If we are to prevent runaway climate change, these new plants can’t be built.”
It also doesn’t make financial sense, according to an analysis by the Rocky Mountain Institute, a Colorado-based think tank that focuses on energy and resource efficiency. By the time most of these power plants are slated to open their doors, the electricity they’ll provide will cost more to produce than clean energy alternatives.
By 2023, the U.S. Energy Information Administration estimates the average cost of producing a megawatt hour of electricity will be $40.20 for a large-scale natural gas plants. Solar installations will be $2.60 cheaper and wind turbines will be $3.60 cheaper.
Catastrophic effects ahead unless we make changes
The world needs to reduce its carbon emissions rapidly – by 50% within the next decade – or face the prospect of a global temperature rise of more than 2.7 degrees within decades, said Michael Mann, a professor of atmospheric sciences at Pennsylvania State University.
That’s enough warming to kill off the coral reefs, melt large parts of the ice sheets, inundate coastal cities and to yield what Mann calls “nearly perpetual extreme weather events.”
“By any definition, that would be catastrophic,” he said.
We’re seeing the start of it now. There’s strong data to suggest that global warming is already causing changes in the jet stream and other weather systems. That can cause hurricanes to slow down and wreak devastation in single areas for longer, said Marshall Shepherd, director of the atmospheric sciences program at the University of Georgia.
“With Dorian, we saw it stall over the Bahamas. We saw that with Harvey in Houston and Florence in the Carolinas,” he said.
More gas = more carbon dioxide
Adding dozens of new natural gas plants in the coming decades is going in the exact opposite direction of what we need, clean energy advocates say.
“If the current pipeline of gas plants were to get built, it would make decarbonizing the power sector by 2050 nearly impossible,” said Joe Daniel, a senior energy analyst with the Union of Concerned Scientists, a nonprofit based in Cambridge, Massachusetts.
An analysis by the Rocky Mountain Institute published Monday looked at 88 gas-fired power plants scheduled to begin operation by 2025. They would emit 100 million tons of carbon dioxide a year – equivalent to 5% of current annual emissions from the U.S. power sector.
The institute calculated the cost of producing a megawatt-hour of electricity of a clean energy portfolio in each state that would provide the same level of power reliability as a gas plant. It determined that building clean energy alternatives would cost less than 90% of the proposed 88 plants.
It would also save customers over $29 billion in their utility bills, said Mark Dyson, an electricity markets analyst who co-authored the Rocky Mountain Institute paper.
“If you look at how things pencil out, we’re at a tipping point,” he said. “Here’s evidence that the switch from gas to clean energy makes economic sense and is compatible with utility companies’ need for reliability.”
More power plants coming to a state near you
USA TODAY compiled its own list of 177 planned and proposed natural gas plants through August, using data from S&P Global Market Intelligence, which tracks power plants that have been officially announced, and the Sierra Club, which tracks proposed plants.
Of those, 152 have a scheduled opening date of between 2019 and 2033, though only 130 have specific locations chosen. An additional 25 are part of companies’ long-term planning processes and don’t have estimated opening dates yet.
The plants are a mix of large-scale installations meant to provide lots of electricity much of the day and smaller plants used for short periods when demand for energy is particularly high.
Texas has the most proposed plants, with 26. Next is Pennsylvania with 24, North Carolina with 12, Florida with 10, California with nine and Montana with eight.
Not all will be built. Power companies are required to estimate future needs and plan as much as 15 years out, and this list includes plants which the companies may eventually decide they don’t need.
But the numbers show that greenhouse gas-producing natural gas is still on the table for many power producers, despite warnings that the energy sector needs to be quickly moving away from carbon-producing power sources.
Another concern raised by clean energy advocates is that once built, natural gas plants typically have a 30-year lifespan. Many of these plants will end up as “stranded assets,” unused because they’re too expensive to run, while consumers will still be on the hook for the cost of the construction, said Daniel.
It’s also true that power companies are building out solar and wind generation. Over the next two years, clean energy is expected to be the fastest-growing source of U.S. electricity generation, according to the U.S. Energy Information Administration.
Even so, that will only bring the share of wind and solar in the United States electricity market to slightly under 11%.
By 2020, EIA expects natural gas will make up about 36% of U.S. electricity generation. In comparison, coal is at 23%, nuclear at 20% and hydroelectric at 7%.
Why are we still building natural gas plants?
If natural gas plants contribute to global warming and most of them are going to be more expensive, why are so many still on the drawing board? The reasons are varied.
Energy companies say gas is more reliable than renewables and cheaper and less carbon polluting than the coal it often replaces.
But renewable energy advocates say the incentives for utilities and energy producers aren’t always in line with those of consumers.
For regulated utilities, one of the easiest ways to make money is to invest capital in large building projects, such as natural gas plants. Regulators allow utilities to set rates so that they get a return on invested capital of about 10%, Dyson said. That gives energy companies an incentive to build as much as possible.
In contrast, utilities that procure wind and solar power via commonly available purchase contracts earn no returns for these projects.
“There’s a perverse incentive for some utilities to build as big as they can, rather than to build as smart as they can,” said Ben Inskeep, an analyst with EQ Research, a clean energy policy consulting firm in Cary, North Carolina.
Companies also focus on reliability. Duke Energy, a power company based in Charlotte, North Carolina, has more than 7 million customers. As it transitions away from coal, it has embraced natural gas, announcing last week that it was considering as many as five new gas plants.
Today 5% of Duke Energy Carolinas’ electricity comes from solar, a percentage it plans to increase to between 8% and 13% by 2034, according to its most recent filing with state regulators. The state has almost no wind energy because of laws restricting the placement of wind turbines.
“We know our customers and communities want cleaner energy, and we’re doing our part to deliver that,” said spokeswoman Erin Culbert.
But she emphasized that Duke doesn’t believe solar and wind can be cost-effective and reliable enough to meet all its customers’ energy needs.
“Continued use of natural gas is key to our ability to speed up coal retirements, and its flexibility helps complement and balance the growing renewables on our system,” she said.
Government regulators favor gas
Another hurdle for renewable energy, some supporters say, is a combination of state-level rate-setting requirements and regional market rules that have led to a compensation structure for companies that favors coal and natural gas.
Who sets those rules depends on where the plant is.
In states where retail utilities own their own power generation facilities, the rates are approved by public utility commissions. Commissioners are typically appointed by state governors.
The process is less clear in the Midwest, Northeast, Mid-Atlantic, California, and Texas, where utilities buy and sell their power through organized markets run by regional transmission organizations.
These are run by boards that by law must be independent. They are typically composed of people from the business and energy world and are chosen by complex systems. In some cases they are voted on by existing board members.
The boards set the rules, which are then approved by the Federal Energy Regulatory Commission.
Ultimately these commissions and boards are supposed to decide what’s cost-effective for both the companies and ratepayers, said Scott Hempling, an adviser to regulators, law professor at Georgetown University in Washington, D.C., and author of two books on public utility law and regulation.
“A utility’s preference for profit is neither surprising nor wrong. But it’s not the utility’s job to balance its self-interest against the customers’ interest. It’s the job of regulators to constrain the private profit impulse with public interest principles,” he said.
It’s not news that there is bias towards profit, which can disadvantage customers. “The question is why it’s allowed to persist,” he said.
There are signs that what clean energy advocates have called an automatic rubber stamp for natural gas is beginning to change.
In April, the Indiana Utility Regulatory Commission denied a permit for a southern Indiana utility named Vectren South to build a $780 million natural gas plant. The regulators weren’t convinced the utility had chosen the best option to ensure its customers weren’t in danger of being “saddled with an uneconomic investment” in the future, it said.
In Michigan last year, local utility DTE won a bruising battle to build a 1,100 megawatt natural gas plant that will open in 2022 and cost nearly $1 billion. Critics complained the projections DTE used to make its case to regulators made wind and solar look less attractive.
The three members of the Michigan Public Service Commission, who are appointed by the governor, ended up approving the project. But the board’s 136-page opinion was not complimentary toward the utility, noting it was “concerned” about the constraints DTE built into the models it used to estimate whether renewable energy would be a viable alternative.
Some utilities choose clean energy
Not every utility company is ignoring warnings about the planet’s health, or customers’ pocketbooks.
Michigan utility Consumers Energy decided last year not to build new natural gas plants and instead focus on a combination of energy efficiency, renewable energy and batteries, which it says will be cheaper for customers.
The company, which has more than 4 million customers, plans to use 90% clean energy by 2040, said Brandon Hofmeister, senior vice president for governmental, regulatory and public affairs.
When the utility was putting together its existing energy plan, it took a new approach, balancing the cost to consumers and to the Earth.
“Honestly, there was some pushback. There were several pretty tense meetings,” Hofmeister said. “You’d hear someone ask in a meeting, ‘Is that really the right thing to do for Michigan and the planet?’”
A similar story played out in Indiana, one of the nation’s top 10 coal-producing states. A few years ago, Northern Indiana Public Service Company, based in Merrillville, Indiana, was getting ready to retire its old, expensive coal-fired power plants. An analysis in 2016 said they should be replaced with natural gas plants.
To be on the safe side, Joe Hamrock, president and CEO, checked again last year.
“We knew this is moving pretty fast and we needed to take a new look. A 30-year bet on a gas plant is a long time,” he said.
When his team sat down to look at the 90 project proposals that had come in, the answer came as a shock – natural gas wasn’t even in the picture anymore.
“The surprise was how dramatically the renewables and storage proposals beat natural gas,” Hamrock said. “I couldn’t have predicted this five years ago.”
The company is now set to retire all its coal-fired power plants, which produce 65% of its electricity today, and replace them all with renewables. In nine years, it expects to get 65% of its electricity from renewables and 25% from natural gas.
What will U.S. energy look like in the future?
Electricity generators counter that it’s impossible to get entirely away from natural gas because solar and wind are intermittent. When it comes time to turn on the lights, consumers can’t wait for the sun to come up or the wind to blow.
“We believe that natural gas has a role in a clean future because we believe it will be needed to balance out renewables,” said Emily Fisher, general counsel for the Edison Electric Institute in Washington, D.C. EEI is the trade association that represents investor-owned electric utilities in the United States.
“But we’ve also got to make sure the power supply stays affordable and reliable,” she said.
Electricity generators have a point, say energy analysts who aren’t necessarily in the pro-renewable camp. But those same analysts suggest a lot less natural gas is needed than we’re using today.
“The cheapest way to reduce carbon is to replace coal with a combination of renewables and as little natural gas as you can get by with to keep the lights on,” said Arne Olson, a senior partner with Energy and Environmental Economics, a San Francisco-based energy consulting firm that works with multiple states to craft energy plans.
That makes getting to the goals of the Paris Agreement on climate change – cutting greenhouse gas emissions at least 26% below 2005 levels by 2025 – not quite so daunting. The United States initially pledged to join the agreement but President Donald Trumpsaid in 2017 that the nation would not uphold the deal.
In fact, the electric industry is already undergoing a major restructuring. Largely because of the rapid rise of cheap natural gas, coal went from producing almost 45% of U.S. electricity in 2010 to a predicted 23% next year, according to EIA data.
The energy sector has shown it can move quickly when the prices are right, said Dyson of the Rocky Mountain Institute. And, he said, it’s imperative that a similar shift happen now with natural gas – and fast.
“Constructing these gas plants is incompatible with a low carbon future,” he said.