Chilean plant to use coal

California Community Choice Aggregators are reshaping electricity markets with renewable energy, solar and wind sourcing, competitive rates, and customer choice, challenging PG&E, SDG&E, and Southern California Edison while advancing California's clean power goals.

Key Points

Local governments that buy power, often cleaner and cheaper, while utilities handle delivery and billing.

✅ Offer higher renewable mix than utilities at competitive rates

✅ Utilities retain transmission and billing responsibilities

✅ Rapid expansion threatens IOU market share across California

Nearly 2 million electricity customers in California may not know it, but they’re part of a revolution. That many residents and businesses are getting their power not from traditional utilities, but via new government-affiliated entities known as community choice aggregators. The CCAs promise to deliver electricity more from renewable sources, such as solar and wind, even as California exports its energy policies across Western states, and for a lower price than the big utilities charge.

The customers may not be fully aware they’re served by a CCA because they’re still billed by their local utility. But with more than 1.8 million accounts now served by the new system and more being added every month, the changes in the state’s energy system already are massive.

Faced for the first time with real competition, the state’s big three utilities have suddenly become havens of innovation. They’re offering customers flexible options on the portion of their power coming from renewable energy, amid a broader review to revamp electricity rates aimed at cleaning the grid, and they’re on pace to increase the share of power they get from solar and wind power to the point where they are 10 years ahead of their deadline in meeting a state mandate.

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But that may not stem the flight of customers. Some estimates project that by late this year, more than 3 million customers will be served by 20 CCAs, and that over a longer period, Pacific Gas & Electric, Southern California Edison, and San Diego Gas & Electric could lose 80% of their customers to the new providers.

Two big customer bases are currently in play: In Los Angeles and Ventura counties, a recently launched CCA called the Clean Power Alliance is hoping by the end of 2019 to serve nearly 1 million customers. Unincorporated portions of both counties and 29 municipalities have agreed in principle to join up.

Meanwhile, the city of San Diego is weighing two options to meet its goal of 100% clean power by 2035, as exit fees are being revised by the utilities commission: a plan to be submitted by SDG&E, or the creation of a CCA. A vote by the City Council is expected by the end of this year. A city CCA would cover 1.4 million San Diegans, accounting for half SDG&E’s customer demand, according to Cody Hooven, the city’s chief sustainability officer.

Don’t expect the big companies to give up their customers without a fight. Indeed, battle lines already are being drawn at the state Public Utilities Commission, where a recent CPUC ruling sided with a community energy program over SDG&E, and local communities.

“SDG&E is in an all-out campaign to prevent choice from happening, so that they maintain their monopoly,” says Nicole Capretz, who wrote San Diego’s climate action plan as a city employee and now serves as executive director of the Climate Action Campaign, which supports creation of the CCA.

California is one of seven states that have legalized the CCA concept, even as regulators weigh whether the state needs more power plants to ensure reliability. (The others are New York, New Jersey, Massachusetts, Ohio, Illinois and Rhode Island.) But the scale of its experiment is likely to be the largest in the country, because of the state’s size and the ambition of its clean-power goal, which is for 50% of its electricity to be generated from renewable sources by 2030.

California created its system via legislative action in 2002. Assembly Bill 117 enabled municipalities and regional governments to establish CCAs anywhere that municipal power agencies weren’t already operating. Electric customers in the CCA zones were automatically signed up, though they could opt out and stay with their existing power provider. The big utilities would retain responsibility for transmission and distribution lines.

The first CCA, Marin Clean Energy, began operating in 2010 and now serves 470,000 customers in Marin and three nearby counties.

The new entities were destined to come into conflict with the state’s three big investor-owned utilities. Their market share already has fallen to about 70%, from 78% as recently as 2010, and it seems destined to keep falling. In part that’s because the CCAs have so far held their promise: They’ve been delivering relatively clean power and charging less.

The high point of the utilities’ hostility to CCAs was the Proposition 16 campaign in 2009. The ballot measure was dubbed the “Taxpayers Right to Vote Act,” but was transparently an effort to smother CCAs in the cradle. PG&E drafted the measure, got it on the ballot, and contributed all of the $46.5 million spent in the unsuccessful campaign to pass it.

As recently as last year, PG&E and SDG&E were lobbying in the legislature for a bill that would place a moratorium on CCAs. The effort failed, and hasn’t been revived this year.

Rhetoric similar to that used by PG&E against Marin’s venture has surfaced in San Diego, where a local group dubbed “Clear the Air” is fighting the CCA concept by suggesting that it could be financially risky for local taxpayers and questioning whether it will be successful in providing cleaner electricity. Whether Clear the Air is truly independent of SDG&E’s parent, Sempra Energy, is questionable, as at least two of its co-chairs are veteran lobbyists for the company.

SDG&E spokeswoman Helen Gao says the utility supports “customers’ right to choose an energy provider that best meets their needs” and expects to maintain a “cooperative relationship” with any provider chosen by the city.

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Alberta Renewable Energy Procurement is surging as corporate PPAs drive wind and solar growth, with the Pembina Institute and the Business Renewables Centre linking buyers and developers in Alberta's energy-only market near Medicine Hat.

Key Points

A market-led approach where corporations use PPAs to secure wind and solar power from Alberta projects.

✅ Corporate PPAs de-risk projects and lock in clean power.

✅ Alberta's energy-only market enables efficient transactions.

✅ Skilled workforce supports wind, solar, legal, and financing.

Alberta has big potential when it comes to providing renewable energy, advocates say.

The Pembina Institute says the practice of corporations committing to buy renewable energy is just taking off in Canada, and Alberta has both the energy sector and the skilled workforce to provide it.

Earlier this week, a company owned by U.S. billionaire Warren Buffett announced a large new wind farm near Medicine Hat. It has a buyer for the power.

Sara Hastings-Simon, director of the Pembina's Business Renewables Centre, says this is part of a trend.

"We're talking about the practice of corporate institutions purchasing renewables to meet their own electricity demand. And this is a really well-established driver for renewable energy development in the U.S.," she said. "You may be hearing headlines like Google, Apple and others that are buying renewables and we're helping to bring this practice to Canada."

The Business Renewables Centre (BRC) is a not-for-profit working to accelerate corporate and institutional procurement of renewables in Canada. The group held its inaugural all members event in Calgary on Thursday.

Hastings-Simon says shareholders and investors are encouraging more use of solar and wind power in Canada.

"We have over 10 gigawatts of renewable energy projects in the pipeline that are ready for buyers. And so we see multinational companies coming to Canada to start to procure here, as well as Canadian companies understanding that this is an opportunity for them as well," Hastings-Simon said.

"It's really exciting to see business interests driving renewable energy development."

Sara Hastings-Simon is the director of the Pembina Institute's Business Renewables Centre, which seeks to build up Alberta's renewable energy industry. (Mike Symington/CBC)

Hastings-Simon says renewable procurement could help dispel the narrative that it's all about oil and gas in Alberta by highlighting Alberta as a powerhouse for both green energy and fossil fuels in Canada.

She says the practice started with a handful of tech companies in the U.S. and has become more mainstream there, even as Canada remains a solar laggard to some observers, with more and more large companies wanting to reduce their energy footprint.

He says his U.S.-based organization has been working for years to speed up and expand the renewables market for companies that want to address their own sustainability.

"We try and make that a little bit easier by building out a community that can help to really reinforce each other, share lessons learned, best practices and then drive for transactions to have actual material impact worldwide," he said.

"We're really excited to be working with the Pembina group and the BRC Canada team," he said. "We feel our best value for this is just to support them with our experiences and lessons. They've been basically doing the same thing for many years helping to grow and grow and cultivate the market."

Porter says Alberta's market is more than ready.

"There are some precedent transactions already so people know it can work," he said. "The way Alberta is structured, being an energy-only market is useful. And I think that there is a strong ecosystem of both budget developers and service providers … that can really help these transactions get over the line."

As procurement ramps up, Hastings-Simon says Alberta already has the skilled workers needed to fill renewable energy jobs across the province.

"We have a lot of the knowledge that's needed, and that's everybody from the construction down through the legal and financing — all those pieces of building big projects," she said. "We are seeing increasing interest in people that want to become involved in that industry, and so there is increasing demand for training in things like solar power installation and wind technicians."

Hastings-Simon predicts an increase in demand for both the services and the workers.

"As this industry ramps up, we're going to need to have more workers that are active in those areas," she said. "So I think we can see a very nice increase — both the demand and the number of folks that are able to work in this field."

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North American Grid Reliability faces extreme weather, climate change, demand spikes, and renewable variability; utilities, AESO, and NERC stress resilience, dispatchable capacity, interconnections, and grid alerts to prevent blackouts during heatwaves and cold snaps.

Key Points

North American grid reliability is the ability to meet demand during extreme weather while maintaining stability.

✅ Extreme heat and cold drive record demand and resource strain.

✅ Balance dispatchable and intermittent generation for resilience.

✅ Expand interconnections, capacity, and demand response to avert outages.

The recent alerts in Alberta's electricity grid during extreme cold have highlighted a broader North American issue, where power systems are more susceptible to being overwhelmed by extreme weather impacts on reliability.

Electricity Canada's chief executive emphasized that no part of the grid is safe from the escalating intensity and frequency of weather extremes linked to climate change across the sector.

“In recent years, during these extreme weather events, we’ve observed record highs in electricity demand,” he stated.

“It’s a nationwide phenomenon. For instance, last summer in Ontario and last winter in Quebec, we experienced unprecedented demand levels. This pattern of extremes is becoming more pronounced across the country.”

The U.S. has also experienced strain on its electricity grids due to extreme weather, with more blackouts than peers documented in studies. Texas faced power outages in 2021 due to winter storms, and California has had to issue several emergency grid alerts during heat waves.

In Canada, Albertans received a government emergency alert two weeks ago, urging an immediate reduction in electricity use to prevent potential rotating blackouts as temperatures neared -40°C. No blackouts occurred, with a notable decrease in electricity use following the alert, according to the Alberta Electric System Operator (AESO).

AESO's data indicates an increase in grid alerts in Alberta for both heatwaves and cold spells, reflecting dangerous vulnerabilities noted nationwide. The period between 2017 and 2020 saw only four alerts, in contrast to 17 since 2021.

Alberta's electricity grid reliability has sparked political debate, including proposals for a western Canadian grid to improve reliability, particularly with the transition from coal-fired plants to increased reliance on intermittent wind and solar power. Despite this debate, the AESO noted that the crisis eased when wind and solar generation resumed, despite challenges with two idled gas plants.

Bradley pointed out that Alberta's grid issues are not isolated. Every Canadian region is experiencing growing electricity demand, partly due to the surge in electric vehicles and clean energy technologies. No province has a complete solution yet.

“Ontario has had to request reduced consumption during heatwaves,” he noted. “Similar concerns about energy mix are present in British Columbia or Manitoba, especially now with drought affecting their hydro-dependent systems.”

The North American Electric Reliability Corporation (NERC) released a report in November warning of elevated risks across North America this winter for insufficient energy supplies, particularly under extreme conditions like prolonged cold snaps.

While the U.S. is generally more susceptible to winter grid disruptions, and summer blackout warnings remain a concern, the report also highlights risks in parts of Canada. Saskatchewan faces a “high” risk due to increased demand, power plant retirements, and maintenance, whereas Quebec and the Maritimes are at “elevated risk.”

Mark Olson, NERC’s manager of reliability assessments, mentioned that Alberta wasn't initially considered at risk, illustrating the challenges in predicting electricity demand amid intensifying extreme weather.

Rob Thornton, president and CEO of the International District Energy Association, acknowledged public concerns about grid alerts but reassured that the risk of a catastrophic grid failure remains very low.

“The North American grid is exceptionally reliable. It’s a remarkably efficient system,” he said.

However, Thornton emphasized the importance of policies for a resilient and reliable electricity system through 2050 and beyond. This involves balancing dispatchable and intermittent electricity sources, investing in extra capacity, enhancing macrogrids and inter-jurisdictional connections, and more.

“These grid alerts raise awareness, if not anxiety, about our energy future,” Thornton concluded.

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Income Graduated Fixed Charge aligns CPUC billing with utility fixed costs, lowers usage rates, supports electrification, and shifts California investor-owned utilities' electric bills by income, with CARE and Climate Credit offsets for low-income households.

Key Points

A CPUC proposal: an income-based monthly fixed fee with lower usage rates to align costs and aid low-income customers.

✅ Income-tiered fixed fees: $0-$42; CARE: $14-$22, by utility territory

✅ Usage rates drop 16%-22% to support electrification and cost-reflective billing

✅ Lowest-income save ~$10-$20; some higher earners pay ~$10+ more monthly

The Public Advocates Office (PAO) for the California Public Utilities Commission (CPUC) has proposed adding a monthly income-based fixed charge on electric utility bills based on income level.  

The rate change is designed to lower bills for the lowest-income residents while aligning billing more directly with utility costs. 

PAO’s recommendation for the Income Graduated Fixed Charge places fees between $22 and $42 per month in the three major investor-owned utilities’ territories, including an SDG&E minimum charge debate under way, for customers not enrolled in the California Alternative Rates for Energy (CARE) program. As seen below, CARE customers would be charged between $14 per month and $22 a month, depending on income level and territory.

For households earning $50,000 or less per year, the fixed charge would be $0, but only if the California Climate Credit is applied to offset the fixed cost.

Meanwhile, usage-based electricity rates are lowered in the PAO proposal, part of major changes to electric bills statewide. Average rates would be reduced between 16% to 22% for the three major investor-owned utilities.

The lowest-income bracket of Californians is expected to save roughly $10 to $20 a month under the proposal, while middle-income customers may see costs rise by about $20 a month, even as lawmakers seek to overturn income-based charges in Sacramento.

“We anticipate the vast majority of low-income customers ($50,000 or less per year) will have their monthly bills decrease by $10 or more, and a small proportion of the highest income earners ($100,000+ per year) will see their monthly bills rise by $10 or more,” said the PAO.

The charges are an effort to help suppress ever-increasing electricity generation and transmission rates, which are among the highest in the country, with soaring electricity prices reported across California. Rates are expected to rise sharply as wildfire mitigation efforts are implemented by the utilities found at fault for their origin.

“We are very concerned. However, we do not see the increases stopping at this point,” Linda Serizawa, deputy director for energy, PAO, told pv magazine. “We think the pace and scale of the [rate] increases is growing faster than we would have anticipated for several years now.”

Consumer advocates and regulators face calls for action on surging electricity bills across the state.

The proposed changes are also meant to more directly couple billing with the fixed charges that utilities incur, as California considers revamping electricity rates to clean the grid. For example, activities like power line maintenance, energy efficiency programs, and wildfire prevention are not expected to vary with usage, so these activities would be funded through a fixed charge.

Michael Campbell of the PAO’s customer programs team, and leader of the proposed program, likened paying for grid enhancements and other social programs with utility rate increases to “paying for food stamps by taxing food.” Instead, a fixed charge would cover these costs.

PAO said the move to lower rates for usage should help encourage electrification as California moves to replace heating and cooling, appliances, and gas combustion cars with electrified counterparts. In addition, lower rates mean the cost burden of running these devices is improved.

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Newfoundland and Labrador Energy Efficiency faces low rankings yet signs of progress: heat pumps, EV charging networks, stricter building codes, electrification to tap Muskrat Falls power and cut greenhouse gas emissions and energy poverty.

Key Points

Policies and programs improving N.L.'s energy use via electrification, EVs, heat pumps, and stronger building codes.

✅ Ranks last provincially but showing policy momentum

✅ Heat pump grants and EV charging network underway

✅ Stronger building codes and electrification can cut emissions

Ah, another day, another depressing study that places Newfoundland and Labrador as lagging behind the rest of Canada.

We've been in this place before — least-fit kids, lowest birthrate — and now we can add a new dubious distinction to the pile: a ranking of the provinces according to energy efficiency placed Newfoundland and Labrador last.

Efficiency Canada released its first-ever provincial scorecard Nov. 20, comparing energy efficiency policies among the provinces. With energy efficiency a key part of reducing greenhouse gas emissions, Newfoundland and Labrador sat in 10th place, noted for its lack of policies on everything from promoting EV uptake in Atlantic Canada to improving efficient construction codes.

But before you click away to a happier story (about, say, a feline Instagram superstar) one of the scorecard's authors says there's a silver lining to the statistics.

"It's not that Newfoundland and Labrador is doing anything badly; it's just that it could do more," said Brendan Haley, the policy director at Efficiency Canada, a new think tank based at Carleton University.

"There's just a general lack of attention to implementing efficiency policies relative to other jurisdictions, including New Brunswick's EV rebate programs on transportation."

Looking at the scorecard and comparing N.L. with British Columbia, which snagged the No. 1 spot, isn't a great look. B.C. scored 56 points out of a possible 100, while N.L. got just 15.

Haley pointed out that B.C.'s provincial government is charting progress toward 2032, when all new builds will have to be net-zero energy ready; that is, buildings that can produce as much clean energy as they consume.  

While it might not be feasible to emulate that to a T here, Haley said the province could be mandating better energy efficiency standards for new, large building projects, and, at the same time, promote electrification of such projects as a way to soak up some of that surplus Muskrat Falls electricity.

Staring down Muskrat's 'extraordinary' pressure on N.L. electricity rates

It's impossible to talk about energy efficiency in N.L. without considering that dam dilemma. As Muskrat Falls comes online, likely at the end of 2020, customer power rates are set to rise in order to pay for it, and the province is still trying to figure out the headache that is rate mitigation.

"There is a strategic choice to be made in Newfoundland and Labrador," Haley told CBC Radio's On The Go.

While having more customers using Muskrat Falls power can help with rate mitigation, including through initiatives like N.L.'s EV push to grow demand, Haley noted simply using its excess electricity for the sake of it isn't a great goal.

"That should not be an excuse, I think, to almost have a policy of wasting energy on purpose, or saying that we don't need programs that help save electricity anymore," he said.

Energy poverty
Lots of N.L. homeowners are currently feeling a chill from the spectre of rising electricity rates.

Of course, that draft could be coming from a poorly insulated and heated house, as Efficiency Canada noted 38 per cent of all households in N.L. live in what it calls "energy poverty," where they spend more than six per cent of their after-tax income on energy — that's the second highest such rate in the country.

That poverty speaks for a need for N.L.to boost efficiency incentives for vulnerable populations, although Haley noted the government is making progress. The province recently expanded its home energy savings program, doubling in the last budget year to $2 million, which gives grants to low income households for upgrades like insulation.

Can you guess what products are selling like hotcakes as Muskrat Falls looms? Heat pumps

And since Efficiency Canada compiled its scorecard, the province has introduced a $1-million heat pump program, in which 1,000 homeowners could receive $1,000 toward the purchase of a heat pump. 

That program began accepting applications Oct. 15, and one month in, has had 682 people apply, according to the Department of Municipal Affairs and Environment, along with thousands of inquiries.

Heat pump popularity
Even without that program, heat pump sales have skyrocketed in the province since 2017. That popularity doesn't come as much of a surprise to Darren Brake, the president of KSAB Construction in Corner Brook.

With more than two decades in the home building business, he's been seeing consumer demand for home energy efficiency rise to the point where a year ago, his company transitioned into only building third-party certified energy efficient homes.

"Everybody's really concerned about the escalating power costs and energy costs, I assume because of Muskrat Falls," he said.

"It's evolving now, as we speak. Everybody is all about that monthly payment."

Brake uses spray foam installation in every house he builds, to seal up any potential leaks. Without sealing the building envelope, he says, a heat pump is far less efficient. (Lindsay Bird/CBC)
And in the weakest housing market in the province in half a century, Brake has been steadily moving his, building and selling seven in the last year.

Brake's houses include heat pumps, but he said the real savings come from their heavily insulated walls, roof and floors. Homeowners looking to install a heat pump in their leaky old house, he said, won't see lower power bills in quite the same way.

"They are energy efficient, but it's more about the building envelope to make a home efficient and easy to heat. You can put a heat pump in an older home that leaks a lot of air, and you won't get the same results," he said.

Charging network coming
The other big piece to the efficiency puzzle — in the scorecard's eyes — is electric vehicles. Those could, again, use some of that Muskrat Falls energy, as well as curtail gas guzzling, but Efficiency Canada pointed to a lack of policies and incentives surrounding electrifying transportation, such as Nova Scotia's vehicle-to-grid pilot that illustrates innovation elsewhere.

Unlike Quebec or B.C., the province doesn't offer a rebate for buying EVs, even as N.W.T. encourages EVs through targeted measures, and while electric vehicles got loud applause at the House of Assembly last week, it was absent of any policy or announcement beyond the province unveiling a EV licence plate design to be used in the near future.

Electric-vehicle charging network planned for N.L. in 2020

But since the scorecard was tallied, NL Hydro has unveiled plans for a Level 3 charging network for EVs across the island, dependent on funding, with N.L.'s first fast-charging network seen as just the beginning for local drivers.

NL Hydro says while its request for proposals for an island-wide charging network closed earlier in November, there is no progress update yet, even as N.B.'s fast-charging rollout advances along the Trans-Canada. (Credit: iStock/Getty Images)
That cash appears to still be in limbo, as "we are still progressing through the funding process," said an NL Hydro spokesperson in an email, with no "additional details to release at this time."

Still, the promise of a charging network — plus the swift uptake on the heat pump program — could boost N.L.'s energy efficiency scorecard next time it's tallied, said Haley.

"It is encouraging to see the province moving forward on smart and efficient electrification," he said.

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Methane Hydrate CO2 Sequestration uses carbon capture and nitrogen injection to swap gases in seafloor hydrates along the Gulf of Mexico, releasing methane for electricity while storing CO2, according to new simulation research.

Key Points

A method injecting CO2 and nitrogen into hydrates to store CO2 while releasing methane for power.

✅ Nitrogen aids CO2-methane swap in hydrate cages, speeding sequestration

✅ Gulf Coast proximity to emitters lowers transport and power costs

✅ Revenue from methane electricity could offset carbon capture

The world is quickly realizing it may need to actively pull carbon dioxide out of the atmosphere to stave off the ill effects of climate change. Scientists and engineers have proposed various carbon capture techniques, but most would be extremely expensive—without generating any revenue. No one wants to foot the bill.

One method explored in the past decade might now be a step closer to becoming practical, as a result of a new computer simulation study. The process would involve pumping airborne CO2 down into methane hydrates—large deposits of icy water and methane right under the seafloor, beneath water 500 to 1,000 feet deep—where the gas would be permanently stored, or sequestered. The incoming CO2 would push out the methane, which would be piped to the surface and burned to generate electricity, whether sold locally or via exporters like Hydro-Que9bec to help defray costs, to power the sequestration operation or to bring in revenue to pay for it.

Many methane hydrate deposits exist along the Gulf of Mexico shore and other coastlines. Large power plants and industrial facilities that emit CO2 also line the Gulf Coast, where EPA power plant rules could shape deployment, so one option would be to capture the gas directly from nearby smokestacks, keeping it out of the atmosphere to begin with. And the plants and industries themselves could provide a ready market for the electricity generated.

A methane hydrate is a deposit of frozen, latticelike water molecules. The loose network has many empty, molecular-size pores, or “cages,” that can trap methane molecules rising through cracks in the rock below. The computer simulation shows that pushing out the methane with CO2 is greatly enhanced if a high concentration of nitrogen is also injected, and that the gas swap is a two-step process. (Nitrogen is readily available anywhere, because it makes up 78 percent of the earth’s atmosphere.) In one step the nitrogen enters the cages; this destabilizes the trapped methane, which escapes the cages. In a separate step, the nitrogen helps CO2 crystallize in the emptied cages. The disturbed system “tries to reach a new equilibrium; the balance goes to more CO2 and less methane,” says Kris Darnell, who led the study, published June 27 in the journal Water Resources Research. Darnell recently joined the petroleum engineering software company Novi Labs as a data scientist, after receiving his Ph.D. in geoscience from the University of Texas, where the study was done.

A group of labs, universities and companies had tested the technique in a limited feasibility trial in 2012 on Alaska’s North Slope, where methane hydrates form in sandstone under deep permafrost. They sent CO2 and nitrogen down a pipe into the hydrate. Some CO2 ended up being stored, and some methane was released up the same pipe. That is as far as the experiment was intended to go. “It’s good that Kris [Darnell] could make headway” from that experience, says Ray Boswell at the U.S. Department of Energy’s National Energy Technology Laboratory, who was one of the Alaska experiment leaders but was not involved in the new study. The new simulation also showed that the swap of CO2 for methane is likely to be much more extensive—and to happen quicker—if CO2 enters at one end of a hydrate deposit and methane is collected at a distant end.

The technique is somewhat similar in concept to one investigated in the early 2010s by Steven Bryant and others at the University of Texas. In addition to numerous methane hydrate deposits, the Gulf Coast has large pools of hot, salty brine in sedimentary rock under the coastline. In this system, pumps would send CO2 down into one end of a deposit, which would force brine into a pipe that is placed at the other end and leads back to the surface. There the hot brine would flow through a heat exchanger, where heat could be extracted and used for industrial processes or to generate electricity, supporting projects such as electrified LNG in some markets. The upwelling brine also contains some methane that could be siphoned off and burned. The CO2 dissolves into the underground brine, becomes dense and sinks further belowground, where it theoretically remains.

Either system faces big practical challenges, and building shared CO2 storage hubs to aggregate captured gas is still evolving. One is creating a concentrated flow of CO2; the gas makes up only .04 percent of air, and roughly 10 percent of the smokestack emission from a typical power plant or industrial facility. If an efficient methane hydrate or brine system requires an input that is 90 percent CO2, for example, concentrating the gas will require an enormous amount of energy—making the process very expensive. “But if you only need a 50 percent concentration, that could be more attractive,” says Bryant, who is now a professor of chemical and petroleum engineering at the University of Calgary. “You have to reduce the [CO2] capture cost.”

Another major challenge for the methane hydrate approach is how to collect the freed methane, which could simply seep out of the deposit through numerous cracks and in all directions. “What kind of well [and pipe] structure would you use to grab it?” Bryant asks.

Given these realities, there is little economic incentive today to use methane hydrates for sequestering CO2. But as concentrations rise in the atmosphere and the planet warms further, and as calls for an electric planet intensify, systems that could capture the gas and also provide energy or revenue to run the process might become more viable than techniques that simply pull CO2 from the air and lock it away, offering nothing in return.

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