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An interview with architect Marc Thorpe on building a cool house powered by the sun.

Architect and Industrial designer Marc Thorpe runs a multi-disciplinary studio in New York. His innovative approach to architecture, branding and furniture design for clients including Under Armour, Moroso and Ligne Roset is rooted in the belief in an architecture of responsibility. His original designs aim to be sustainable and affordable. He recently collaborated with Stage Six (who scale social enterprise) and affordable housing social enterprise group, Échale International on a sustainable and ecologically responsible housing development in Uganda. Each home, constructed of soil bricks, has its own water tower to collect rainwater in case of drought.
I spoke with Marc about Fremont House, he and his wife’s concept home built to showcase how off-grid living can be both stylish and affordable. Our conversation has been edited for length and clarity.
What is your general architecture approach/design?
Our approach is straightforward, simple, and legible. In the case of the several homes I’ve built upstate, it’s really been more about just trying to bring some degree of taste and sophistication to the language of architecture upstate using local vernacular. But at the same time, I’m approaching it utilizing renewable technology. The short of it is to keep everything tight and local, integrate renewable tech, and push for that 100% win/win.

How did you achieve this at the Fremont House?
We wanted to test out the solar concept along with the rectilinearity of the house. How can we keep the house as passive as possible so it doesn’t lose heat and cooling?
To start, we made the entire house solar-powered. It is not tied to the grid out of the gate. So, a zero dollar energy bill. The panels are all on the roof and are designed to accommodate southern exposure. The solar powers everything — lights, internet, appliances.
We all focused on the rectilinearity of the house, which is a passive move. We used platonic forms as a square, with 90 degree angles which make for an easier opportunity to lock it up and not lose cool. It’s also naturally cross-ventilated. There is no AC in the house whatsoever.
It’s heated with a wood burning stove and an energy efficient dyson heater inside the utility room which provides heat for piping and is always maintained at 55 degrees.
In winter, we make a fire, and because it’s square, the house doesn’t lose energy. It’s easier to heat than a house with different angles. Also the house has very few windows, so we are not losing heat that way.

How did you adapt the design for different seasons? Doesn’t it get boiling hot in summer?
Summer doesn’t get boiling hot here. The house is between Roscoe and Callicoon, New York, near Lake Tana. The area stays cool and rarely gets above 80 degrees. The cross ventilation allows the heat to move through the house naturally, it rises and goes straight out the window.
It’s also possible, if you need it, to put in an electric heat pump and a mini-split would provide AC.
Your Habitable score shows … wow, you barely have any climate risk! Not even for heat! Were you aware of that when you built here?
I didn’t know this when we were building, but I always knew the climate was super moderate here. There is lots of rain, lots of sun. It’s sort of a perfect place and also gets a lot of snow.
What decisions did you take to build the Catskill House for its environment?
We mostly had to work around hot and cold.
Also the roof panels are black and the roof is black so it retains heat. And when there is snowfall on it, the black has a faster heat coefficient to warm the snow so it melts quicker. The roof also is on an angle so the snow will fall right off — a natural cleaning too.

What would you have done differently now that you are living in it?
We finished Fremont House at the end of last year. So as of December 1, it will have been one full year.
Lessons learned? Its’ a two-story. In the future, we will build a one story. There’s just an ease of access to the roof when you need to get up there. Cleaning windows on the second level is a pain.
Otherwise, everything works perfectly. In the dead of winter, the house can heat up from freezing to 70 within a few hours. It has a small footprint, only 1,000 square feet (500 up and 500 downstairs) so a fire warms the whole house.
For the next house we do in North Branch that we are building to sell, we will execute a lot of these lessons. We will use the same approach and build according to the same concepts.
What are your three top takeaways for people who want to live off grid
1. Just take the position of being autonomous. Understand that you don’t need to rely on the system, on the grid. You don’t need to rely on anything. You can take responsibility for yourself and do it on your own.
2. You don’t need to sacrifice design to have a sustainable home. There’s a stigma around some of this stuff that is unjustified. It’s possible to have a well-designed home that is fully functioning without the powers pushing fossil fuels as the only solution.
3. There are so many opportunities to get off the grid: solar, geothermal, and other technologies. It’s worth the effort.
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My colleague Emily Pontecorvo has a fascinating story today about Net Power, an energy and power development company whose technology once seemed key to decarbonizing the country’s electricity grid.
When Net Power went public in 2023, it was working on a natural gas-burning power plant that would generate little to no emissions in part by using carbon capture and storage. Its invention seemed to have big implications, and not just for the company’s bottom line: Back then, the Environmental Protection Agency was drafting climate rules that would have required new natural gas plants built in the 2030s to capture their carbon dioxide emissions. Net Power’s technology seemed like one of the best available ways to meet that standard.
Cut to 2026, and the world looks different. Thanks to the artificial intelligence boom, electricity demand is surging. But Net Power hasn’t successfully commercialized its proprietary power plant technology. Even if it had, few companies are willing to pay the high premium required by Net Power’s technology, especially when cheaper options are available. And the government certainly isn’t going to require it. Emily’s story reveals what happened next.
When I helped start Heatmap more than three years ago, I never thought I would write this much about data centers. I believed that electricity demand growth was inevitable, sure, and I thought the U.S. power grid had to expand for the country to decarbonize. But I didn’t foresee such a staggering near-term surge in electricity demand. (To be fair, even long-time students of the computing industry’s energy use didn’t see the coming increase, either.)
What I didn’t anticipate — or understand — were two fast-moving trends. The first was that the AI models were responding to scale: the more text or images they consumed, or training they received, or (crucially) computational power they had access to, the better they got. The second was that Wall Street was happy to pay to continue that speedy scale-up. As long as models kept getting better, investors were willing to keep lending or investing more money to the companies making them. Through the power of those two scaling functions, the data center boom became one of the biggest infrastructure buildouts in American history.
In recent days, the second of those trends has started to falter. After a surprisingly hot inflation report last week, and a disclosure on Wednesday evening that Meta has gone free cash flow negative to finance its ongoing AI buildout, stocks with any proximity to AI or data centers stumbled on Wall Street today. The data center developers Coreweave and Vistra were each down about 10%, while Microsoft, Alphabet, and Nvidia all fell in daily trading. Meta’s stock lost almost 7% of its value; GE Vernova, which produces gas turbines, was down 10%.
These declines look more significant when you zoom out. Since late June, a good chunk of the AI portfolio has sagged into the red. Coreweave’s stock is down 54% over the past six months. Alphabet and GE Vernova have also posted declines since the summer. (The trend isn’t uniform: Nvidia and Microsoft are still very much in the green.)
None of this, to be sure, guarantees that the AI boom is ending or even slowing down. But this finance-applied friction is what such a slowdown could look like. Investors aren’t (yet) saying that AI is a business dud, to be clear, just that companies perhaps don’t need to go and construct all this stuff so fast. And given what the data center buildout has meant for energy construction — not to mention greenhouse gas emissions — that’s a trend nobody in climate or energy can ignore.
The zero-emission pioneer is doing the dirty work for the AI boom.
All kinds of companies have refashioned themselves to exploit the AI boom. A bitcoin miner became a data center developer, a shoemaker is building GPUs, and an electric vehicle company is integrating its powertrains into server racks.
Now, a company that once aspired to build one of the lowest-emitting power plants has pivoted to building one of the dirtiest in order to meet data centers’ requirement for speed to power above all. Net Power was founded to pioneer a new form of natural gas power plant with zero emissions, but it has given up on that technology and recently acquired 10 natural gas reciprocating engines that it plans to co-locate with a data center on the site intended for its first commercial plant.
“We believe the clean piece is important,” Net Power CEO Danny Rice said during an August earnings call when he announced the company’s pivot to building unabated natural gas plants. “But just as it’s always been, it will only come at scale once society’s basic energy pillars of reliable, affordable power are fully in place. Power demand is outstripping supply today.”
Net Power’s pivot is a sign not only that the AI boom has eroded market appetite for clean power, but that U.S. policies supporting carbon capture — primarily the 45Q tax credit that President Trump’s One Big Beautiful Bill Act recently expanded — are still not enough to support the technology’s deployment in the power sector.
“The long history of doing CCS in the United States is there isn’t enough public funding to get companies to deploy it at scale,” Jack Andreasen Cavanaugh, a senior research associate at Columbia University’s Center on Global Energy Policy, told me.
This is actually the second major pivot the company has made in less than a year. Last November, Net Power was still testing its proprietary oxy-combustion technology at its demonstration site in La Porte, Texas. The tech was designed to burn natural gas in a chamber with pure oxygen, producing a purer stream of CO2 than when natural gas is burned in regular air. Net Power’s system could recycle some of that CO2 for power generation and capture the rest more efficiently than a conventional gas plant could. The company had not yet demonstrated that the system could generate more energy than it used, however.
By that point, Net Power had determined that its oxy-combustion plants, if they ever even did generate net power, would not be economically competitive anytime soon. In its 2025 Q3 financial report, the company said it had “decided to broaden the scope of its business” and develop more conventional natural gas plants with carbon capture equipment tacked on. It signed a letter of intent with Entropy, a Canadian company building “post-combustion” carbon capture equipment, to bring the tech to the United States, and ordered two 30-megawatt Siemens natural gas turbines for 2028 delivery.
“For us and everyone else in the power and data center space these days, speed is everything,” Rice said at the time. “We believe gas turbines with [post-combustion capture] can and should be the fastest-to-market and most cost-competitive clean, firm solution for our prospective customers.”
He told investors that rising costs were one of the setbacks Net Power faced in building its first-of-a-kind oxy-combustion plant. It was highly unlikely the company could finance and build a $1.7 billion, 200-megawatt plant before completing all its testing, he said. The best-case scenario for the plant to come online was 2030 or 2031, and costs might keep rising with inflation. The company could either bet on that prospect and keep bleeding cash, or “slow down that spending in order to free up some of our resources for near-term accretive opportunities.” As a public company with shareholders to answer to, there was really only one choice.
By the end of 2025, Net Power decided to suspend its oxy-combustion development and testing activities altogether, according to its year-end SEC filing.
Six months later, the company’s thesis changed again. Gas turbines with post-combustion capture, it turned out, were not the “fastest-to-market and most cost-competitive” solutions that the company had hoped they’d be. Whereas once upon a time, electricity buyers considered a range of factors when shopping around for power, including carbon emissions, the reality was that they were now only looking for three qualities: speed, reliability, and scale. “Natural gas power generation, co-located with customer load, and deployable on a fast timeline, is how we expect to meet that demand today,” Rice told investors, adding that the company hoped to add carbon capture to its projects in the future.
To date, only one proposed U.S. natural gas plant with carbon capture has announced a deal to sell its prospective power. In October 2025, Google signed a power purchase agreement with the Broadwing Energy Center, an Illinois plant under development by a company called Low Carbon Infrastructure.
“There is a massive demand for unabated gas right now, and there is much less of a demand for carbon capture,” Cavanaugh said. He told me there are still lots of conversations happening between hyperscalers and carbon capture companies, but the physical realities and costs of capturing, transporting, and storing carbon from natural gas plants remain obstacles.
The Global CCS Institute published its annual Global Status of CCS report this week, which found more than 266 carbon capture, transport, or storage projects are under development in the U.S., but permitting delays and policy uncertainty are stalling their progress. “Inflation and rising capital costs have weakened project economics, reducing the effectiveness of existing policies, such as tax and investment credits,” the report said.
That doesn’t mean there aren’t still companies trying. Net Power may have given up on oxy-combustion power plants for now, but Arbor Energy, a startup founded by former SpaceX engineers, is just ramping up. Arbor announced a milestone in the development of its own oxy-combustion power generator last week, running a key piece of its system — a supercritical CO2 turbocompressor — for more than two hours at high speeds.
Arbor differentiates itself by using 3D-printed turbines and developing smaller, more modular plants. It’s scaling more incrementally than Net Power tried to, starting with a 1-megawatt demonstration plant in California that is “weeks away” from operating, the company’s Chief Operating Officer Alicia Harmon told me — although the project won’t include carbon storage. It plans to build a 25-megawatt demonstration plant by 2028, also sans storage, before manufacturing commercial-scale systems.
Arbor actually went through a pivot of its own due to the data center boom. The founders originally planned to focus on bioenergy with carbon removal, using the oxy-combustion technology to generate power from biomass and storing the resulting CO2 underground. Over time, though, it became clear that demand for power outpaced demand for carbon removal, and natural gas was more abundant than biomass.
I asked Harmon whether the company thought there was market demand for carbon-capture gas plants. Is anyone willing to pay that green premium right now? “Honestly, my answer is no,” she said, but the company sees a path to erasing the green premium by the early 2030s. She added that Arbor’s technology is already “very close” to parity with combined-cycle natural gas plants when the 45Q tax credit is taken into account.
Last month, Net Power announced it had acquired 123 megawatts’ worth of Wärtsilä reciprocating engines, in addition to the Siemens turbines it had already ordered. Reciprocating engines are among the dirtiest natural gas power-generation technologies. A recent report from Earthjustice estimated that a 1-gigawatt plant powered by reciprocating engines would emit 1.5 times as much CO2 per year as one powered by the “combined cycle” technology most modern plants use, and twice as much nitrogen oxides and fine particulate matter. It has not yet disclosed any data center partners to sell the power to.
Net Power declined to comment on this story.
Ben Allen wants to reform the existing market. Jane Kim wants a revolution.
From Crescent City to Coronado, California voters are facing decisions on a down-ballot strewn with over a dozen propositions and a series of statewide Democrat-versus-Republican races with mostly foregone conclusions.
And then there’s the insurance commissioner.
In the race to oversee California’s insurance market, a $452 billion-in-premium-volume monster imperiled by insurer defections and disaster risks, Democratic State Senator Ben Allen, whose district includes Pacific Palisades, is facing off against Jane Kim, a progressive former San Francisco supervisor.
Kim has the support of Vermont Senator Bernie Sanders — it’s the first thing you see about her when you Google her campaign. She previously served as his California political director during the 2020 presidential race, and she appeared earlier this month at an event with the senator in support of the state’s proposed billionaire wealth tax.
Allen, by contrast, won the endorsement of the state’s Democratic Party and its two incumbent senators.
There has been little public polling of the race, but one September survey showed Kim leading Allen 25% to 18%, with more than half the electorate undecided.
“My opponent and I are not even running for the same office,” Kim told me. “He’s running for what this office used to be, and I’m running for what this office could be.”
Allen wasn’t worried about Kim’s characterization in my interview with him, telling me, “I want to fix the market that we have and make it work. My opponent wants to build a new state insurer that nobody has priced.”
Nowhere are the stakes of insurance regulation higher than in California. On its own, the state’s insurance market would be the third largest in the world, according to the National Association of Insurance Commissioners. Homeowner insurance premiums have risen 84% from the end of 2020 to March 2026, according to research from Stanford’s Climate and Energy Policy Program. Several large insurers have either left the market entirely or stopped writing new policies.
California’s creaky and complex regulatory environment for insurers has combined with its famously flammable environment (all beset by a warming climate) to put regular policyholders at risk of losing their policies or bailing out those who can’t get covered. “Climate risks grow, and our mechanisms for dealing with it lag behind,” Matt Weiner, the chief executive of the wildfire policy group Megafire Action, told me. (Weiner said he was supporting Allen in his personal capacity).
Rates for homes insured by the FAIR Plan, the barebones insurer of last resort, have more than doubled from about 2% to 5% over that same period, with FAIR Plan coverage spreading from just high-risk areas to even areas with low and moderate wildfire risk. The plan required a $1 billion assessment from the state’s insurers in 2025 following major Southern California fires. “This trend is a symptom of many homeowners’ inability to secure insurance in the conventional market,” according to the Stanford researchers.
Allen seeks to make the insurance market work better, building on reforms implemented by current Insurance Commissioner Ricardo Lara. Allen described the reforms, which encourage insurers to write policies in high-risk areas and allow them to use forward-looking projections, as a “bit of a band-aid” that doesn’t “actually get to the core of the problem, which is making these communities less risky.”
Allen’s plan for the California insurance market involves both reviewing rate proposals more quickly, incorporating more data into those rates (which may push rates up, but also keep insurers in the market), and mobilizing the whole of government to invest in home hardening and resilience to lower risk and bring premiums down. Allen wants to, well, insure “that risk reduction is actually incentivized and rewarded by the insurance market,” he told me.
This would mean that “there will continue to be certain properties that are going to be so high risk that they really will and ought to be paying significantly more than everybody else,” he added.
When I asked him to elaborate on his vision for California’s insurance future, he told me, “My hope is that when a family and a neighborhood commit to hardening defensible space and community-scale mitigation, that should show up on the bill.”
Jane Kim, on the other hand, is interested in an insurance revolution, which would require — as her most famous supporter might put it — a political revolution as well. Her centerpiece proposal will be familiar from anyone who has followed Sanders’ career: a single-payer disaster insurer.
The plan, which she told me was a “concept and a proposal,” would be funded by a levy placed on insurers, and then a public insurer would invest in the market, buy reinsurance, and pay out claims. (Her opponents have criticized her for not being forthcoming enough with details). She says her plan would not be able to cover a Palisades- or Altadena-level fire in its first year, “but no insurance company can cover a catastrophe of that level.”
The nonprofit nature of the program, she adds, would let the state fund mitigation work directly. While such a program would require legislative action, “the great thing about campaigns is that this is trying to debate big ideas with voters,” Kim said.
In response, Allen cited a report from the California Earthquake Authority, which modeled a state disaster insurer (albeit not Kim’s plan specifically) could require $25 billion in capitalization. A more thinly capitalized insurer could mean $2,000 assessments on every policyholder in the state to cover an extreme wildfire disaster, the report said. “That’s the honest price of what she’s proposing,” Allen said.
“I also have a plan that’s actually grounded in reality and fixing the problems right now. It's not based on some pie-in-the-sky set of ideas that have no precedent, that have no real meat on the bones,” Allen told me.
One of Allen and Kim’s former opponents, Patrick Wolff, who fell short in the top-two primary election in June, told me that “the charitable interpretation of Kim’s platform is she does not think the current system can be made to work, and so she essentially wants to redesign and reimagine the entire system.” (Wolff has endorsed Allen). But, he added, “she’s coming at it from a set of solutions that were baked-in before she started, and then she's fitting [those] into her campaign.”
Moira Birss, a senior fellow at the Climate and Community Institute who said she had “provided input” to Kim’s campaign, but wasn’t speaking on its behalf, told me she “really recognizes that we are yet again in a situation where the private insurance market is not responding to a need that we as communities and as society have for this financial safety net of disaster insurance, and that we need a public approach.” She said the plan would build on lessons learned from New Zealand, which has public natural disaster insurance funded through a levy on fire insurance, and from the National Flood Insurance Program and the FAIR Plan.
Kim is happy to embrace the more ideologically charged vision of her campaign, telling me, “I am talking about transforming this office to be a place where we are leading on, and taking on, economic inequity, a wealth gap, and the climate crisis.
“I don’t even view my opponent as Ben Allen — I’m not running against Ben Allen,” she went on. “I’m running against the status quo.”