Two coal plants to be iced

UK Hydrogen Storage Caverns enable long-duration, low-carbon electricity balancing, storing surplus wind and solar power as green hydrogen in salt formations to enhance grid reliability, energy security, and net zero resilience by 2035 and 2050.

Key Points

They are salt caverns storing green hydrogen to balance wind and solar, stabilizing a low-carbon UK grid.

✅ Stores surplus wind and solar as green hydrogen in salt caverns

✅ Enables long-duration, low-carbon grid balancing and security

✅ Complements wind and solar; reduces dependence on flexible CCS

The U.K. government must kick-start the construction of large-scale hydrogen storage facilities if it is to meet its pledge that all electricity will come from low-carbon electricity sources by 2035 and reach legally binding net zero targets by 2050, according to a report by the Royal Society.

The report, "Large-scale electricity storage," published Sep. 8, examines a wide variety of ways to store surplus wind and solar generated electricity—including green hydrogen, advanced compressed air energy storage (ACAES), ammonia, and heat—which will be needed when Great Britain's electricity generation is dominated by volatile wind and solar power.

It concludes that large scale electricity storage is essential to mitigate variations in wind and sunshine, particularly long-term variations in the wind, and to keep the nation's lights on. Storing most of the surplus as hydrogen, in salt caverns, would be the cheapest way of doing this.

The report, based on 37 years of weather data, finds that in 2050 up to 100 Terawatt-hours (TWh) of storage will be needed, which would have to be capable of meeting around a quarter of the U.K.'s current annual electricity demand. This would be equivalent to more than 5,000 Dinorwig pumped hydroelectric dams. Storage on this scale, which would require up to 90 clusters of 10 caverns, is not possible with batteries or pumped hydro.

Storage requirements on this scale are not currently foreseen by the government, and the U.K.'s energy transition faces supply delays. Work on constructing these caverns should begin immediately if the government is to have any chance of meeting its net zero targets, the report states.

Sir Chris Llewellyn Smith FRS, lead author of the report, said, "The need for long-term storage has been seriously underestimated. Demand for electricity is expected to double by 2050 with the electrification of heat, transport, and industrial processing, as well as increases in the use of air conditioning, economic growth, and changes in population.

"It will mainly be met by wind and solar generation. They are the cheapest forms of low-carbon electricity generation, but are volatile—wind varies on a decadal timescale, so will have to be complemented by large scale supply from energy storage or other sources."

The only other large-scale low-carbon sources are nuclear power, gas with carbon capture and storage (CCS), and bioenergy without or with CCS (BECCS). While nuclear and gas with CCS are expected to play a role, they are expensive, especially if operated flexibly.

Sir Peter Bruce, vice president of the Royal Society, said, "Ensuring our future electricity supply remains reliable and resilient will be crucial for our future prosperity and well-being. An electricity system with significant wind and solar generation is likely to offer the lowest cost electricity but it is essential to have large-scale energy stores that can be accessed quickly to ensure Great Britain's energy security and sovereignty."

Combining hydrogen with ACAES, or other forms of storage that are more efficient than hydrogen, could lower the average cost of electricity overall, and would lower the required level of wind power and solar supply.

There are currently three hydrogen storage caverns in the U.K., which have been in use since 1972, and the British Geological Survey has identified the geology for ample storage capacity in Cheshire, Wessex and East Yorkshire. Appropriate, novel business models and market structures will be needed to encourage construction of the large number of additional caverns that will be needed, the report says.

Sir Chris observes that, although nuclear, hydro and other sources are likely to play a role, Britain could in principle be powered solely by wind power and solar, supported by hydrogen, and some small-scale storage provided, for example, by batteries, that can respond rapidly and to stabilize the grid. While the cost of electricity would be higher than in the last decade, we anticipate it would be much lower than in 2022, he adds.

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Hinkley Point C dome lift marks a nuclear reactor milestone in Somerset, as EDF used Big Carl crane to place a 245-tonne steel roof, enabling 2027 startup amid costs, delays, and precision indoor welding.

Key Points

A 245-tonne dome lifted onto Hinkley Point C's first reactor, finishing the roof and enabling fit-out for a 2027 startup.

✅ 245-tonne steel dome lifted by Big Carl onto 44m-high reactor

✅ Indoor welding avoided weather defects seen at Flamanville

✅ Cost now £33bn; first power targeted by end of 2027

Engineers have lifted a steel roof onto a building which will house the first of two nuclear reactors at Hinkley Point in Somerset.

Hundreds of people helped with the delicate operation to get the 245-tonne steel dome into position.

It means the first reactor can be installed next year, ready to be switched on in June 2027.

Engineers at EDF said the "challenging job" was completed in just over an hour.

They first broke the ground on the new nuclear station in March 2017. Now, some 10,000 people work on what is Europe's largest building site.

Yet many analysts note that Europe is losing nuclear power even as demand for reliable energy grows.

They have faced delays from Covid restrictions and other recent setbacks, and the budget has doubled to £33bn, so getting the roof on the first of the two reactor buildings is a big deal.

EDF's nuclear island director Simon Parsons said it was a "fantastic night".

"Lifting the dome into place is a celebration of all the work done by a fantastic team. The smiles on people's faces this morning were something else.

"Now we can get on with the fitting of equipment, pipes and cables, including the first reactor which is on site and ready to be installed next year."

Nuclear minister Andrew Bowie hailed the "major milestone" in the building project, citing its role in the UK's green industrial revolution ambitions.

He said: "This is a key part of the UK Government's plans to revitalise nuclear."

But many still question whether Hinkley Point C will be worth all the money, especially after Hitachi's project freeze in Britain, with Roy Pumfrey of the Stop Hinkley campaign describing the project as "shockingly bad value".

Why lift the roof on?

The steel dome is bigger than the one on St Paul's Cathedral in London.

To lift it onto the 44-metre-high reactor building, they needed the world's largest land-based crane, dubbed Big Carl by engineers.

So why not just build the roof on top of the building?

The answer lies in a remote corner of Normandy in France, near a village called Flamanville.

EDF has been building a nuclear reactor there since 2007, ten years before they started in west Somerset.

The project is now a decade behind schedule and has still not been approved by French regulators.

Why? Because of cracks found in the precision welding on the roof of the reactor building.

In nuclear-powered France, they built the roof in situ, out in the open. 

Engineers have decided welding outside, exposed to wind and rain, compromised the high standards needed for a nuclear reactor.

So in Somerset they built a temporary workshop, which looks like a fair sized building itself. All the welding has been done inside, and then the completed roof was lifted into place.

Is it on time or on budget?

No, neither. When Hinkley C was first approved a decade ago, EDF said it would cost £14bn.

Four years later, in 2017, they finally started construction. By now the cost had risen to £19.5bn, and EDF said the plant would be finished by the end of 2025.

Today, the cost has risen to £33bn, and it is now hoped Hinkley C will produce electricity by the end of 2027.

"Nobody believes it will be done by 2027," said campaigner Roy Pumfrey.

"The costs keep rising, and the price of Hinkley's electricity will only get dearer," they added.

On the other hand, the increase in costs is not a problem for British energy bill payers, or the UK government.

EDF agreed to pay the full cost of construction, including any increases.

When I met Grant Shapps, then the UK Energy Secretary, at the site in April, he shrugged off the cost increases.

He said: "I think we should all be rather pleased it is not the British tax payer - it is France and EDF who are paying."

In return, the UK government agreed a set rate for Hinkley's power, called the Strike Price, back in 2013. The idea was this would guarantee the income from Hinkley Point for 35 years, allowing investors to get their money back.

Will it be worth the money?

Back in 2013, the Strike Price was set at £92.50 for each megawatt hour of power. At the time, the wholesale price of electricity was around £50/MWh, so Hinkley C looked expensive.

But since then, global shocks like the war in Ukraine have increased the cost of power substantially, and advocates argue next-gen nuclear could deliver smaller, cheaper, safer designs.

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Hydro One-Avista Acquisition secures U.S. antitrust clearance under Hart-Scott-Rodino, pending approvals from state utility commissions, the FCC, and CFIUS, with prior FERC approval and shareholder vote supporting the cross-border utility merger.

Key Points

A $6.7B cross-border utility merger cleared under HSR, still awaiting state, FCC, and CFIUS approvals; FERC approved earlier.

✅ HSR waiting period expired; U.S. antitrust clearance obtained

✅ Approvals pending: state commissions, FCC, and CFIUS

✅ FERC and Avista shareholders have approved the transaction

Hydro One Ltd. says it has received antitrust clearance in the United States for its deal to acquire U.S. energy company Avista Corp., even as it sought to redesign customer bills in Ontario.

The Ontario-based utility says the 30-day waiting period under the Hart-Scott-Rodino Antitrust Improvements Act expired Thursday night.

Hydro One announced the friendly deal to acquire Avista last summer, amid customer backlash in some service areas, in an agreement that valued the company at $6.7 billion.

The deal still requires several other approvals, including those from utility commissions in Washington, Idaho, Oregon, Montana and Alaska.

Analysts also warned of political risk for Hydro One during this period, reflecting concerns about provincial influence.

The U.S. Federal Communications Commission must also sign off on the transaction, and although U.S. regulators later rejected the $6.7B takeover following review, clearance is required by the Committee on Foreign Investment in the United States.

The agreement has received approval from the U.S. Federal Energy Regulatory Commission as well as Avista shareholders, and it mirrored other cross-border deals such as Algonquin Power's acquisition of Empire District that closed in the sector.

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Puerto Rico Earthquakes continue as a seismic swarm with aftershocks, landslides near Pef1uelas, damage in Ponce and Guayanilla, grid outages from Costa Sur Plant, PREPA recovery, vulnerable buildings post-Hurricane Maria raising safety concerns.

Key Points

Recurring seismic events impacting Puerto Rico, causing damage, aftershocks, outages, and displacement.

✅ Seismic swarm with 6.4 and 5.9 magnitude quakes and ongoing aftershocks

✅ Costa Sur Plant offline; PREPA urges conservation amid grid repairs

✅ Older, code-deficient buildings and landslides raise safety risks

Some in Puerto Rico are beginning to fear the ground will never stop shaking. The island has been pummeled by hundreds of earthquakes in recent weeks, including the recent 5.9 magnitude temblor, where there were reports of landslides in the town of Peñuelas along the southern coast, rattling residents already on edge from the massive 6.4 magnitude quake, and raising wider concerns about climate risks to the grid in disaster-prone regions.

That was the largest to strike the island in more than a century causing hundreds of structures to crumble, forcing thousands from their homes and leaving millions without power, a scenario echoed by Texas power outages during winter storms too. One person was killed and several others injured.

Utility says 99% of customers have electricity

Puerto Rico's public utility, PREPA, tweeted some welcome news Monday: that nearly all of the homes and businesses it serves have had electric power restored. Still it is urging customers to conserve energy amid utility supply-chain shortages that can slow critical repairs.

Reporting from the port city of Ponce, NPR's Adrian Florido said the Costa Sur Plant, which produces more than 40% of Puerto Rico's electricity, was badly damaged in last week's quake. It remains offline indefinitely, even as grid operators elsewhere have faced California blackout warnings during extreme heat.

He also reports many residents are still reeling from the devastation caused by Hurricane Maria, a deadly Category 4 storm that battered the island in September 2017. The storm exposed the fact that buildings across the island were not up to code, similar to how aging systems have contributed to PG&E power line fires in California. The series of earthquakes are only amplifying fears that structures have been further weakened.

"People aren't coping terribly well," Florido said on NPR's Morning Edition Monday, noting that households elsewhere have endured pandemic power shutoffs and burdensome bills.

Many earthquake victims sleeping outdoors

Florido spoke to one displaced resident, Leticia Espada, who said more than 50 homes in her town of Guayanilla, about an hour drive east of the port city of Ponce, had collapsed.

After sleeping outside for days on her patio following Tuesday's quake, she eventually came to her town's baseball stadium where she's been sleeping on one of hundreds of government-issued cots.

She's like so many others sleeping in open-air shelters, many unwilling to go back to their homes until they've been deemed safe, while even far from disaster zones, brief events like a Northeast D.C. outage show how fragile service can be.

"Thousands of people across several towns sleeping in tents or under tarps, or out in the open, protected by nothing but the shade of a tree with no sense of when these quakes are going to stop," Florido reports.

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California Wildfire Smoke Impact on Solar reduces photovoltaic output, as particulate pollution, soot, and haze dim sunlight and foul panels, cutting utility-scale generation and grid reliability across CAISO during peak demand and heatwaves.

Key Points

How smoke and soot cut solar irradiance and foul panels, slashing PV generation and straining CAISO grid operations.

✅ Smoke blocks sunlight; soot deposition reduces panel efficiency.

✅ CAISO reported ~30% drop versus July during peak smoke.

✅ Longer fire seasons threaten solar reliability and capacity planning.

Smoke from California’s unprecedented wildfires was so bad that it cut a significant chunk of solar power production in the state, even as U.S. solar generation rose in 2022 nationwide. Solar power generation dropped off by nearly a third in early September as wildfires darkened the skies with smoke, according to the US Energy Information Administration.

Those fires create thick smoke, laden with particles that block sunlight both when they’re in the air and when they settle onto solar panels. In the first two weeks of September, soot and smoke caused solar-powered electricity generation to fall 30 percent compared to the July average, according to the California Independent System Operator (CAISO), which oversees nearly all utility-scale solar energy in California, where wind and solar curtailments have been rising amid grid constraints. It was a 13.4 percent decrease from the same period last year, even though solar capacity in the state has grown about 5 percent since September 2019.

California depends on solar installations for nearly 20 percent of its electricity generation, and has more solar capacity than the next five US states trailing it combined as it works to manage its solar boom sustainably. It will need even more renewable power to meet its goal of 100 percent clean electricity generation by 2045, building on a recent near-100% renewable milestone that underscored the transition. The state’s emphasis on solar power is part of its long-term efforts to avoid more devastating effects of climate change. But in the short term, California’s renewables are already grappling with rising temperatures.

Two records were smashed early this September that contributed to the loss of solar power. California surpassed 2 million acres burned in a single fire season for the first time (1.7 million more acres have burned since then). And on September 15th, small particle pollution reached the highest levels recorded since 2000, according to the California Air Resources Board. Winds that stoked the flames also drove pollution from the largest fires in Northern California to Southern California, where there are more solar farms.

Smaller residential and commercial solar systems were affected, too, and solar panels during grid blackouts typically shut off for safety, although smoke was the primary issue here. “A lot of my systems were producing zero power,” Steve Pariani, founder of the solar installation company Solar Pro Energy Systems, told the San Mateo Daily Journal in September.

As the planet heats up, California’s fire seasons have grown longer, and blazes are tearing through more land than ever before, while grid operators are also seeing rising curtailments as they integrate more renewables. For both utilities and smaller solar efforts, wildfire smoke will continue to darken solar energy’s otherwise bright future, even as it becomes the No. 3 renewable source in the U.S. by generation.

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Power Grid Attacks surge across substations and transmission lines, straining critical infrastructure as DHS and FBI cite vandalism, domestic extremists, and cybersecurity risks impacting resilience, outages, and grid reliability nationwide.

Key Points

Power Grid Attacks are deliberate strikes on substations and lines to disrupt power and weaken grid reliability.

✅ Physical attacks rose across multiple states and utilities.

✅ DHS and FBI warn of threats to critical infrastructure.

✅ Substation security and grid resilience upgrades urged.

Even before Christmas Day attacks on power substations in five states in the Pacific Northwest and Southeast, similar incidents of attacks, vandalism and suspicious activity were on the rise.

Federal energy reports through August – the most recent available – show an increase in physical attacks at electrical facilities across the nation this year, continuing a trend seen since 2017.

At least 108 human-related events were reported during the first eight months of 2022, compared with 99 in all of 2021 and 97 in 2020. More than a dozen cases of vandalism have been reported since September.

The attacks have prompted a flurry of calls to better protect the nation's power grid, with a renewed focus on protecting the U.S. power grid across sectors, but experts have warned for more than three decades that stepped-up protection was needed.

Attacks on power stations on the rise 
Twice this year, the Department of Homeland Security warned "a heightened threat environment" remains for the nation, including its critical infrastructure amid reports of suspected Russian breaches of power plant systems. 

At least 20 actual physical attacks were reported, compared with six in all of 2021. 
Suspicious-activity reports jumped three years ago, nearly doubling in 2020 to 32 events. In the first eight months of this year, 34 suspicious incidents were reported.
Total human-related incidents – including vandalism, suspicious activity and cyber events such as Russian hackers and U.S. utilities in recent years – are on track to be the highest since the reports started showing such activity in 2011.

Attacks reported in at least 5 states
Since September, attacks or potential attacks have been reported on at least 18 additional substations and one power plant in Florida, Oregon, Washington and the Carolinas. Several involved firearms.

• In Florida: Six "intrusion events" occurred at Duke Energy substations in September, resulting in at least one brief power outage, according to the News Nation television network, which cited a report the utility sent to the Energy Department. Duke Energy spokesperson Ana Gibbs confirmed a related arrest, but the company declined to comment further.
• In Oregon and Washington state: Substations were attacked at least six times in November and December, with firearms used in some cases, local news outlets reported. On Christmas Day, four additional substations were vandalized in Washington State, cutting power to more than 14,000 customers.
• In North Carolina: A substation in Maysville was vandalized on Nov. 11. On Dec. 3, shootings that authorities called a "targeted attack" damaged two power substations in Moore County, leaving tens of thousands without power amid freezing temperatures.
• In South Carolina: Days later, gunfire was reported near a hydropower plant, but police said the shooting was a "random act."

It's not yet clear whether any of the attacks were coordinated. After the North Carolina attacks, a coordinating council between the electric power industry and the federal government ordered a security evaluation.

FBI mum on its investigations
The FBI is looking into some of the attacks, including cyber intrusions where hackers accessed control rooms in past cases, but it hasn't said how many it's investigating or where. 

Shelley Lynch, a spokesperson for the FBI's Charlotte field office, confirmed the bureau was investigating the North Carolina attack. The Kershaw County Sheriff's Office reported the FBI was looking into the South Carolina incident.

Utilities in Oregon and Washington told news outlets they were cooperating with the FBI, but spokespeople for the agency's Seattle and Portland field offices said they couldn't confirm or deny an investigation.

Could domestic extremists be involved?
In January, the Department of Homeland Security said domestic extremists had been developing "credible, specific plans" since at least 2020, including a Neo-Nazi plot against power stations detailed in a federal complaint, and would continue to "encourage physical attacks against electrical infrastructure."

In February, three men who ascribed to white supremacy and Neo-Nazism pleaded guilty to federal crimes related to a scheme to attack the grid with rifles.

In a news release, Timothy Langan, assistant director of the FBI’s Counterterrorism Division, said the defendants "wanted to attack regional power substations and expected the damage would lead to economic distress and civil unrest."

Why is the power grid so hard to protect?
Industry experts, federal officials and others have warned in one report after another since at least 1990 that the power grid was at risk, and a recent grid vulnerability report card highlights dangerous weak points, said Granger Morgan, an engineering professor at Carnegie Mellon University who chaired three National Academies of Sciences reports.

The reports urged state and federal agencies to collaborate to make the system more resilient to attacks and natural disasters such as hurricanes and storms. 

"The system is inherently vulnerable, with the U.S. grid experiencing more blackouts than other developed nations in one study. It's spread all across the countryside," which makes the lines and substations easy targets, Morgan said. The grid includes more than 7,300 power plants, 160,000 miles of high-voltage power lines and 55,000 transmission substations.

One challenge is that there's no single entity whose responsibilities span the entire system, Morgan said. And the risks are only increasing as the grid expands to include renewable energy sources such as solar and wind, he said. 

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