U.S. adds wind energy to 400,000 homes

Nighttime Thermoelectric Generator converts radiative cooling into renewable energy, leveraging outer space cold; a Stanford-UCLA prototype complements solar, serving off-grid loads with low-power output during peak evening demand, using simple materials on a rooftop.

Key Points

A device converting nighttime radiative cooling into electricity, complementing solar for low-power evening needs.

✅ Uses thermocouples to convert temperature gradients to voltage.

✅ Exploits radiative cooling to outer space for night power.

✅ Complements solar; low-cost parts suit off-grid applications.

Two years ago, one freezing December night on a California rooftop, a tiny light shone weakly with a little help from the freezing night air. It wasn't a very bright glow. But it was enough to demonstrate the possibility of generating renewable power after the Sun goes down.

Working with Stanford University engineers Wei Li and Shanhui Fan, University of California Los Angeles materials scientist Aaswath Raman put together a device that produces a voltage by channelling the day's residual warmth into cooling air, effectively generating electricity from thin air with passive heat exchange.

"Our work highlights the many remaining opportunities for energy by taking advantage of the cold of outer space as a renewable energy resource," says Raman.

"We think this forms the basis of a complementary technology to solar. While the power output will always be substantially lower, it can operate at hours when solar cells cannot."

For all the merits of solar energy, it's just not a 24-7 source of power, although research into nighttime solar cells suggests new possibilities for after-dark generation. Sure, we can store it in a giant battery or use it to pump water up into a reservoir for later, but until we have more economical solutions, nighttime is going to be a quiet time for renewable solar power. 

Most of us return home from work as the Sun is setting, and that's when energy demands spike to meet our needs for heating, cooking, entertaining, and lighting.

Unfortunately, we often turn to fossil fuels to make up the shortfall. For those living off the grid, it could require limiting options and going without a few luxuries.

Shanhui Fan understands the need for a night time renewable power source well. He's worked on a number of similar devices, including carbon nanotube generators that scavenge ambient energy, and a recent piece of technology that flipped photovoltaics on its head by squeezing electricity from the glow of heat radiating out of the planet's Sun-warmed surface.

While that clever item relied on the optical qualities of a warm object, this alternative device makes use of the good old thermoelectric effect, similar to thin-film waste-heat harvesting approaches now explored.

Using a material called a thermocouple, engineers can convert a change in temperature into a difference in voltage, effectively turning thermal energy into electricity with a measurable voltage. This demands something relatively toasty on one side and a place for that heat energy to escape to on the other.

The theory is the easy part – the real challenge is in arranging the right thermoelectric materials in such a way that they'll generate a voltage from our cooling surrounds that makes it worthwhile.

To keep costs down, the team used simple, off-the-shelf items that pretty much any of us could easily get our hands on.

They put together a cheap thermoelectric generator and linked it with a black aluminium disk to shed heat in the night air as it faced the sky. The generator was placed inside a polystyrene enclosure sealed with a window transparent to infrared light, and linked to a single tiny LED.

For six hours one evening, the box was left to cool on a roof-top in Stanford as the temperature fell just below freezing. As the heat flowed from the ground into the sky, the small generator produced just enough current to make the light flicker to life.

At its best, the device generated around 0.8 milliwatts of power, corresponding to 25 milliwatts of power per square metre.

That might just be enough to keep a hearing aid working. String several together and you might just be able to keep your cat amused with a simple laser pointer. So we're not talking massive amounts of power.

But as far as prototypes go, it's a fantastic starting point. The team suggests that with the right tweaks and the right conditions, 500 milliwatts per square metre isn't out of the question.

"Beyond lighting, we believe this could be a broadly enabling approach to power generation suitable for remote locations, and anywhere where power generation at night is needed," says Raman.

While we search for big, bright ideas to drive the revolution for renewables, it's important to make sure we don't let the smaller, simpler solutions like these slip away quietly into the night.

This research was published in Joule.

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France Electricity Pricing Mechanism aligns with EU rules, leveraging nuclear energy and EDF profits, avoiding Contracts for Difference, redistributing windfalls to industry and households, targeting €70/MWh amid electricity market reform and Brussels oversight.

Key Points

A framework to keep power near €70/MWh by reclaiming EDF windfalls and redistributing them under EU market rules.

✅ Targets average price near €70/MWh from 2026

✅ Skims EDF profits above €78-80 and €110/MWh thresholds

✅ Aligns with EU rules; avoids nuclear CfDs and state aid clashes

France has unveiled a new electricity pricing mechanism, hoping to defuse months of tension over energy subsidies with Brussels and its neighbors.

The strain has included a Franco-German fight over EU electricity reform with Germany accusing France of wanting to subsidize its industry via artificially low energy prices, while Paris maintained it should have the right to make the most of its relatively cheap nuclear energy. That fight has now been settled.

On Tuesday, the French government presented a new mechanism — complex, and still-to-be-detailed — to bring the average price of electricity closer to €70 per megawatt hour (MWh) as of 2026, amid Europe's electricity market revamp efforts.

"The agreement has been defined to comply with European rules and avoid difficulties with the European Commission," said France's Economy and Finance Minister Bruno Le Maire, noting that France had ruled out other "simpler" options that would have caused tension with Brussels.

For example, France has not yet envisaged the use of state-backed investment schemes called Contracts for Difference (CfD), which were the main source of discord in talks with Germany on the electricity market reform and the EU push for more fixed-price contracts in generation. The compromise agreed by EU ministers last month gives the Commission the power to monitor CfDs in the nuclear sector.

"France wanted to limit as much as possible the European Commission's nuisance power," said Phuc-Vinh Nguyen, an energy expert at the Jacques Delors Institute think tank in Paris.

The announcement came weeks after French President Emmanuel Macron promised that France would "take back control" of its electricity prices to allow its industry to make the most of the country's relatively cheap nuclear energy.

Germany, by contrast, has moved to support energy-intensive industries with an industrial electricity subsidy, underscoring the policy divergence.

“The price of electricity has always been a major competitive advantage for the French nation, and it must remain so,” Le Maire said.

Under the new mechanism, part of a broader deal on electricity prices between the state and EDF, the government will seize EDF profits above certain thresholds and redistribute them directly to industry and households to bring prices closer to the desired level. Specifically, the government will redistribute 50 percent of EDF’s additional profits if prices rise above €78-€80 per MWh, and 90 percent of extra profits if prices rise above €110 per MWh.

The move also marks a new step in the government's power grab at EDF, after the company was fully nationalized earlier this year.

For years, France has been discussing an EDF reform with the Commission in order to address concerns by Brussels regarding disguised state aid to the company. In particular, the Commission wanted assurances that any state aid given to nuclear would be kept separate from those parts of the business subject to competition, such as renewable energy development.

An economy ministry official close to Le Maire argued that the new pricing mechanism would settle matters with Brussels on that front. A Commission spokesperson said Brussels was in contact with France on the file, but declined further comment.

The mechanism will replace the existing EU-mandated energy pricing mechanism, dubbed ARENH, which was set to expire at the end of 2025, and which has forced EDF to sell some of its electricity to competitors at a fixed low price since 2010, and comes amid contested electricity market reforms at EU level.

The new system could benefit EDF because it won't be bound to sell energy at a lower price, but instead will be allowed to auction off its energy to competitors. On the other hand, the redistribution system would deprive the company of some profits when electricity prices are higher. No wonder, then, that negotiations between the government and EDF have been "difficult," as Le Maire put it.

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ABL has secured a contract for the UK Subsea Power Link, highlighting ABL Group’s marine warranty role in Eastern Green Link 2, a 2 GW offshore electricity superhighway connecting Scotland and England to enhance grid reliability and renewable energy transmission.

Key Points: ABL Group’s contract for the UK Subsea Power Link

ABL Group has been appointed to provide marine warranty survey services for the 2 GW Eastern Green Link 2 subsea interconnector between Scotland and England.

✅ Manages vessel suitability checks, installation oversight, and DP assurance

✅ Strengthens UK grid reliability and advances the clean energy transition

✅ Sizeable contract valued between USD 1 million and 3 million

Energy and marine consultancy ABL, a subsidiary of ABL Group, has been awarded a contract by Eastern Green Link 2 (EGL2) to provide marine warranty survey (MWS) services for the installation of a new 2 GW subsea power connection between Scotland and England.

EGL2 is one of the United Kingdom’s most significant energy-infrastructure projects, involving the creation of a 505-kilometre “electricity superhighway” that will enable simultaneous power transfer between Peterhead in Aberdeenshire and Drax in North Yorkshire, mirroring a renewable power link announced for the same corridor recently. The project is designed to strengthen grid resilience, integrate renewable energy from Scotland’s offshore resources, and advance the UK’s broader energy transition goals.

Under the terms of the contract, ABL will be responsible for the technical review and approval of the project and procedural documentation, as well as conducting suitability surveys of the proposed fleet for marine transportation and installation operations. The company will also provide dynamic positioning (DP) assurance where required and will review and approve all warranted operations through on-site attendances, reflecting practices used on projects like the Great Northern Transmission Line in North America.

Cable-laying operations for the link are scheduled to take place between January and September 2028, amid wider efforts to fast-track grid connections across the UK. According to ABL, the engagement represents a “sizeable” contract, valued between USD 1 million and 3 million.

“This appointment reflects ABL's reputation as a trusted MWS partner for major power transmission infrastructure development and reinforces our position at the forefront of supporting the UK's energy transition,” said Hege Norheim, CEO of ABL Group. “We look forward to contributing to this strategic initiative.”

The subsea interconnector, known as Eastern Green Link 2, will transmit up to 2 gigawatts of electricity—enough to power approximately 2 million homes. It forms part of the Great Grid Upgrade, National Grid’s nationwide program to modernize and expand the transmission network in preparation for a low-carbon future, alongside a recent 2 GW substation milestone.

By linking renewable-rich northern Scotland with high-demand regions in England, EGL2 is expected to reduce congestion on the existing grid by leveraging HVDC technology to improve transfer efficiency, enhance security of supply, and facilitate the more efficient flow of surplus renewable energy south. The connection will also support the UK government’s target of decarbonizing the electricity system by 2035.

ABL’s appointment follows a period of intensive marine and geotechnical surveys along the proposed cable route to assess seabed conditions and environmental sensitivities. The company’s marine warranty oversight will ensure that transportation and installation operations meet strict safety, technical, and environmental standards demanded by insurers and project partners, as seen in a recent cross-border transmission approval in North America.

For ABL Group, which provides engineering and risk services to the offshore energy and marine industries worldwide, the contract marks another milestone in its expanding portfolio of subsea power and transmission projects across Europe. With operations set to begin in 2028, the Eastern Green Link 2 initiative represents both a major engineering challenge and a key enabler of the UK’s offshore energy ambitions, echoing a recent offshore wind power milestone in the U.S.

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Franco-German Nuclear Power Divide shapes EU energy policy, electricity market reform, and decarbonization strategies, as Paris backs reactors and state subsidies while Berlin prioritizes renewables, hydrogen, and energy security after Russian gas shocks.

Key Points

A policy rift over nuclear shaping EU market reform, subsidies, and the balance between reactors and renewables.

✅ Nuclear in EU targets vs. renewables-first strategy

✅ Market design disputes over long-term power prices

✅ Energy security after Russian gas; hydrogen definitions

Near the French village of Fessenheim, facing Germany across the Rhine, a nuclear power station stands dormant. The German protesters that once demanded the site’s closure have decamped, in a sign of Europe's nuclear decline, and the last watts were produced three years ago. 

But disagreements over how the plant from 1977 should be repurposed persist, speaking to a much deeper divide over nuclear power, which Eon chief's warning to Germany underscored, between the two countries on either side of the river’s banks.

German officials have disputed a proposal to turn it into a centre to treat metals exposed to low levels of radioactivity, Fessenheim’s mayor Claude Brender says. “They are not on board with anything that might in some way make the nuclear industry more acceptable,” he adds.

France and Germany’s split over nuclear power is a tale of diverging mindsets fashioned over decades, including since the Chernobyl disaster in USSR-era Ukraine. But it has now become a major faultline in a touchy relationship between Europe’s two biggest economies.

Their stand-off over how to treat nuclear in a series of EU reforms has consequences for how Europe plans to advance towards cleaner energy. It will also affect how the bloc secures power supplies as the region weans itself off Russian gas, even though nuclear would do little for the gas issue, and how it provides its industry with affordable energy to compete with the US and China. 

“There can be squabbles between partners. But we’re not in a retirement home today squabbling over trivial matters. Europe is in a serious situation,” says Eric-André Martin, a specialist in Franco-German relations at French think-tank IFRI. 

France, which produces two-thirds of its power from nuclear plants and has plans for more reactors, is fighting for the low-carbon technology to be factored into its targets for reducing emissions and for leeway to use state subsidies to fund the sector.

For Germany, which closed its last nuclear plants this year and, having turned its back on nuclear, has been particularly shaken by its former reliance on Russian gas, there’s concern that a nuclear drive will detract from renewable energy advances.

But there is also an economic subtext in a region still reeling from an energy crisis last year, reviving arguments for a needed nuclear option for climate in Germany, when prices spiked and laid bare how vulnerable households and manufacturers could become.

Berlin is wary that Paris would benefit more than its neighbours if it ends up being able to guarantee low power prices from its large nuclear output as a result of new EU rules on electricity markets, amid talk of a possible U-turn on the phaseout, people close to talks between the two countries say.

Ministers on both sides have acknowledged there is a problem. “The conflict is painful. It’s painful for the two governments as well as for our [EU] partners,” Sven Giegold, state secretary at the German economy and climate action ministry, where debates about whether a nuclear resurgence is possible persist, tells the Financial Times. 

Agnès Pannier-Runacher, France’s energy minister, says she wants to “get out of the realm of the emotional and move past the considerable misunderstandings that have accumulated in this discussion”.

In a joint appearance in Hamburg last week, German chancellor Olaf Scholz and French president Emmanuel Macron made encouraging noises over their ability to break the latest deadlock: a disagreement over the design of the EU’s electricity market. Ministers had been due to agree a plan in June but will now meet on October 17 to discuss the reform, aimed at stabilising long-term prices.

But the French and German impasse on nuclear has already slowed down debates on key EU policies such as rules on renewable energy and how hydrogen should be produced. Smaller member states are becoming impatient. The delay on the market design is “a big Franco-German show of incompetence again”, says an energy ministry official from another EU country who requested anonymity. 

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Hydroelectric retrofits for unpowered dams leverage turbines to add renewable capacity, bolster grid reliability, and enable low-impact energy storage, supporting U.S. and Canada decarbonization goals with lower costs, minimal habitat disruption, and climate resilience.

Key Points

They add turbines to existing dams to make clean power, stabilize the grid, and offer low-impact storage at lower cost.

✅ Lower capex than new dams; minimal habitat disruption

✅ Adds firming and storage to support wind and solar

✅ New low-head turbines unlock more retrofit sites

As countries race to get their power grids off fossil fuels to fight climate change, there's a big push in the U.S. to upgrade dams built for purposes such as water management or navigation with a feature they never had before — hydroelectric turbines. 

And the strategy is being used in parts of Canada, too, with growing interest in hydropower from Canada supplying New York and New England.

The U.S. Energy Information Administration says only three per cent of 90,000 U.S. dams currently generate electricity. A 2012 report from the U.S. Department of Energy found that those dams have 12,000 megawatts (MW) of potential hydroelectric generation capacity. (According to the National Hydropower Association, 1 MW can power 750 to 1,000 homes. That means 12,000 MW should be able to power more than nine million homes.)

As of May 2019, there were projects planned to convert 32 unpowered dams to add 330 MW to the grid over the next several years.

One that was recently completed was the Red Rock Hydroelectric Project, a 60-year-old flood control dam on the Des Moines River in Iowa that was retrofitted in 2014 to generate 36.4 MW at normal reservoir levels, and up to 55 MW at high reservoir levels and flows. It started feeding power to the grid this spring, and is expected to generate enough annually to supply power to 18,000 homes.

It's an approach that advocates say can convert more of the grid from fossil fuels to clean energy, often with a lower cost and environmental impact than building new dams.

Hydroelectric facilities can also be used for energy storage, complementing intermittent clean energy sources such as wind and solar with pumped storage to help maintain a more reliable, resilient grid.

The Nature Conservancy and the World Wildlife Fund are two environmental groups that oppose new hydro dams because they can block fish migration, harm water quality, damage surrounding ecosystems and release methane and CO2, and in some regions, Western Canada drought has reduced hydropower output as reservoirs run low. But they say adding turbines to non-powered dams can be part of a shift toward low-impact hydro projects that can support expansion of solar and wind power.

Paul Norris, president of the Ontario Waterpower Association, said there's typically widespread community support for such projects in his province amid ongoing debate over whether Ontario is embracing clean power in its future plans. "Any time that you can better use existing assets, I think that's a good thing."

New turbine technology means water doesn't need to fall from as great a height to generate power, providing opportunities at sites that weren't commercially viable in the past, Norris said, with recent investments such as new turbines in Manitoba showing what is possible.

In Ontario, about 1,000 unpowered dams are owned by various levels of government. "With the appropriate policy framework, many of these assets have the potential to be retrofitted for small hydro," Norris wrote in a letter to Ontario's Independent Electricity System Operator this year as part of a discussion on small-scale local energy generation resources.

He told CBC that several such projects are already in operation, such as a 950 kW retrofit of the McLeod Dam at the Moira River in Belleville, Ont., in 2008. 

Four hydro stations were going to be added during dam refurbishment on the Trent-Severn Waterway, but they were among 758 renewable energy projects cancelled by Premier Doug Ford's government after his election in 2018, a move examined in an analysis of Ontario's dirtier electricity outlook and its implications.

Patrick Bateman, senior vice-president of Waterpower Canada, said such dam retrofit projects are uncommon in most provinces. "I don't see it being a large part of the future electricity generation capacity."

He said there has been less movement on retrofitting unpowered dams in Canada compared to the U.S., because:

There are a lot more opportunities in Canada to refurbish large, existing hydro-generating stations to boost capacity on a bigger scale.

There's less growth in demand for clean energy, because more of Canada's grid is already non-carbon-emitting (80 per cent) compared to the U.S. (40 per cent).

Even so, Norris thinks Canadians should be looking at all opportunities and options when it comes to transitioning the grid away from fossil fuels, including retrofitting non-powered dams, especially as a recent report highlights Canada's looming power problem over the coming decades.

"If we're going to be serious about addressing the inevitable challenges associated with climate change targets and net zero, it really is an all-of-the-above approach."

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PG&E Wind Shutdown and Renewable Reliability examines PSPS strategy, wildfire risk, transmission line exposure, wind turbine cut-out speeds, grid stability, and California's energy mix amid historic high-wind events and supply constraints across service areas.

Key Points

An overview of PG&E's PSPS decisions, wildfire mitigation, and how wind cut-out limits influence grid reliability.

✅ Wind turbines reach cut-out near 55 mph, reducing generation.

✅ PSPS mitigates ignition from damaged transmission infrastructure.

✅ Baseload diversity improves resilience during high-wind events.

According to the official, widely reported story, Pacific Gas & Electric (PG&E) initiated power shutoffs across substantial portions of its electric transmission system in northern California as a precautionary measure.

Citing high wind speeds they described as “historic,” the utility claims that if it didn’t turn off the grid, wind-caused damage to its infrastructure could start more wildfires.

Perhaps that’s true. Perhaps. This tale presumes that the folks who designed and maintain PG&E’s transmission system are unaware of or ignored the need to design it to withstand severe weather events, and that the Federal Energy Regulatory Commission (FERC) and North American Electric Reliability Corp. (NERC) allowed the utility to do so.

Ignorance and incompetence happens, to be sure, but there’s much about this story that doesn’t smell right—and it’s disappointing that most journalists and elected officials are apparently accepting it without question.

Take, for example, this statement from a Fox News story about the Kincade Fires: “A PG&E meteorologist said it’s ‘likely that many trees will fall, branches will break,’ which could damage utility infrastructure and start a fire.”

Did you ever notice how utilities cut wide swaths of trees away when transmission lines pass through forests? There’s a reason for that: When trees fall and branches break, the grid can still function, and even as the electric rhythms of New York City shifted during COVID-19, operators planned for variability.

So, if badly designed and poorly maintained infrastructure isn’t the reason PG&E cut power to millions of Californians, what might have prompted them to do so? Could it be that PG&E’s heavy reliance on renewable energy means they don’t have the power to send when a “historic” weather event occurs, especially as policymakers weigh the postponed closure of three power plants elsewhere in California?

Wind Speed Limits

The two most popular forms of renewable energy come with operating limitations, which is why some energy leaders urge us to keep electricity options open when planning the grid. With solar power, the constraint is obvious: the availability of sunlight. One doesn’t generate solar power at night and energy generation drops off with increasing degrees of cloud cover during the day.

The main operating constraint of wind power is, of course, wind speed, and even in markets undergoing 'transformative change' in wind generation, operators adhere to these technical limits. At the low end of the scale, you need about a 6 or 7 miles-per-hour wind to get a turbine moving. This is called the “cut-in speed.” To generate maximum power, about a 30 mph wind is typically required. But, if the wind speed is too high, the wind turbine will shut down. This is called the “cut-out speed,” and it’s about 55 miles per hour for most modern wind turbines.

It may seem odd that wind turbines have a cut-out speed, but there’s a very good reason for it. Each wind turbine rotor is connected to an electric generator housed in the turbine nacelle. The connection is made through a gearbox that is sized to turn the generator at the precise speed required to produce 60 Hertz AC power.

The blades of the wind turbine are airfoils, just like the wings of an airplane. Adjusting the pitch (angle) of the blades allows the rotor to maintain constant speed, which, in turn, allows the generator to maintain the constant speed it needs to safely deliver power to the grid. However, there’s a limit to blade pitch adjustment. When the wind is blowing so hard that pitch adjustment is no longer possible, the turbine shuts down. That’s the cut-out speed.

Now consider how California’s power generation profile has changed. According to Energy Information Administration data, the state generated 74.3 percent of its electricity from traditional sources—fossil fuels and nuclear, amid debates over whether to classify nuclear as renewable—in 2001. Hydroelectric, geothermal, and biomass-generated power accounted for most of the remaining 25.7 percent, with wind and solar providing only 1.98 percent of the total.

By 2018, the state’s renewable portfolio had jumped to 43.8 percent of total generation, with clean power increasing and wind and solar now accounting for 17.9 percent of total generation. That’s a lot of power to depend on from inherently unreliable sources. Thus, it wouldn’t be at all surprising to learn that PG&E didn’t stop delivering power out of fear of starting fires, but because it knew it wouldn’t have power to deliver once high winds shut down all those wind turbines

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