Markets are broken, Pennsylvania officials told

Power Grid Climate Resilience demands storm hardening, underground power lines, microgrids, batteries, and renewable energy as regulators and utilities confront climate change, sea level rise, and extreme weather to reduce outages and protect vulnerable communities.

Key Points

It is the grid capacity to resist and recover from climate hazards using buried lines, microgrids, and batteries.

✅ Underground lines reduce wind outages and wildfire ignition risk.

✅ Microgrids with solar and batteries sustain critical services.

✅ Regulators balance cost, resilience, equity, and reliability.

Every time a storm lashes the Carolina coast, the power lines on Tonye Gray’s street go down, cutting her lights and air conditioning. After Hurricane Florence in 2018, Gray went three days with no way to refrigerate medicine for her multiple sclerosis or pump the floodwater out of her basement.

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“Florence was hell,” said Gray, 61, a marketing account manager and Wilmington native who finds herself increasingly frustrated by the city’s vulnerability.

“We’ve had storms long enough in Wilmington and this particular area that all power lines should have been underground by now. We know we’re going to get hit.”

Across the nation, severe weather fueled by climate change is pushing aging electrical systems past their limits, often with deadly results. Last year, amid increasing nationwide blackouts, the average American home endured more than eight hours without power, according to the U.S. Energy Information Administration — more than double the outage time five years ago.

This year alone, a wave of abnormally severe winter storms caused a disastrous power failure in Texas, leaving millions of homes in the dark, sometimes for days, and at least 200 dead. Power outages caused by Hurricane Ida contributed to at least 14 deaths in Louisiana, as some of the poorest parts of the state suffered through weeks of 90-degree heat without air conditioning.

As storms grow fiercer and more frequent, environmental groups are pushing states to completely reimagine the electrical grid, incorporating more grid-scale batteries, renewable energy sources and localized systems known as “microgrids,” which they say could reduce the incidence of wide-scale outages. Utility companies have proposed their own storm-proofing measures, including burying power lines underground.

But state regulators largely have rejected these ideas, citing pressure to keep energy rates affordable. Of $15.7 billion in grid improvements under consideration last year, regulators approved only $3.4 billion, according to a national survey by the NC Clean Energy Technology Center — about one-fifth, highlighting persistent vulnerabilities in the grid nationwide.

After a weather disaster, “everybody’s standing around saying, ‘Why didn’t you spend more to keep the lights on?’ ” Ted Thomas, chairman of the Arkansas Public Service Commission, said in an interview with The Washington Post. “But when you try to spend more when the system is working, it’s a tough sell.”

A major impediment is the failure by state regulators and the utility industry to consider the consequences of a more volatile climate — and to come up with better tools to prepare for it. For example, a Berkeley Lab study last year of outages caused by major weather events in six states found that neither state officials nor utility executives attempted to calculate the social and economic costs of longer and more frequent outages, such as food spoilage, business closures, supply chain disruptions and medical problems.

“There is no question that climatic changes are happening that directly affect the operation of the power grid,” said Justin Gundlach, a senior attorney at the Institute for Policy Integrity, a think tank at New York University Law School. “What you still haven’t seen … is a [state] commission saying: 'Isn’t climate the through line in all of this? Let’s examine it in an open-ended way. Let’s figure out where the information takes us and make some decisions.’ ”

In interviews, several state commissioners acknowledged that failure.

“Our electric grid was not built to handle the storms that are coming this next century,” said Tremaine L. Phillips, a commissioner on the Michigan Public Service Commission, which in August held an emergency meeting to discuss the problem of power outages. “We need to come up with a broader set of metrics in order to better understand the success of future improvements.”

Five disasters in four years
The need is especially urgent in North Carolina, where experts warn Atlantic grids and coastlines need a rethink as the state has declared a federal disaster from a hurricane or tropical storm five times in the past four years. Among them was Hurricane Florence, which brought torrential rain, catastrophic flooding and the state’s worst outage in over a decade in September 2018.

More than 1 million residents were left disconnected from refrigerators, air conditioners, ventilators and other essential machines, some for up to two weeks. Elderly residents dependent on oxygen were evacuated from nursing homes. Relief teams flew medical supplies to hospitals cut off by flooded roads. Desperate people facing closed stores and rotting food looted a Wilmington Family Dollar.

“I have PTSD from Hurricane Florence, not because of the actual storm but the aftermath,” said Evelyn Bryant, a community organizer who took part in the Wilmington response.

The storm reignited debate over a $13 billion proposal by Duke Energy, one of the largest power companies in the nation, to reinforce the state’s power grid. A few months earlier, the state had rejected Duke’s request for full repayment of those costs, determining that protecting the grid against weather is a normal part of doing business and not eligible for the type of reimbursement the company had sought.

After Florence, Duke offered a smaller, $2.5 billion plan, along with the argument that severe weather events are one of seven “megatrends” (including cyberthreats and population growth) that require greater investment, according to a PowerPoint presentation included in testimony to the state. The company owns the two largest utilities in North Carolina, Duke Energy Carolinas and Duke Energy Progress.

Vote Solar, a nonprofit climate advocacy group, objected to Duke’s plan, saying the utility had failed to study the risks of climate impacts. Duke’s flood maps, for example, had not been updated to reflect the latest projections for sea level rise, they said. In testimony, Vote Solar claimed Duke was using environmental trends to justify investments “it had already decided to pursue.”

The United States is one of the few countries where regulated utilities are usually guaranteed a rate of return on capital investments, even as studies show the U.S. experiences more blackouts than much of the developed world. That business model incentivizes spending regardless of how well it solves problems for customers and inspires skepticism. Ric O’Connell, executive director of GridLab, a nonprofit group that assists state and regional policymakers on electrical grid issues, said utilities in many states “are waving their hands and saying hurricanes” to justify spending that would do little to improve climate resilience.

In North Carolina, hurricanes convinced Republicans that climate change is real

Duke Energy spokesman Jeff Brooks acknowledged that the company had not conducted a climate risk study but pointed out that this type of analysis is still relatively new for the industry. He said Duke’s grid improvement plan “inherently was designed to think about future needs,” including reinforced substations with walls that rise several feet above the previous high watermark for flooding, and partly relied on federal flood maps to determine which stations are at most risk.

Brooks said Duke is not using weather events to justify routine projects, noting that the company had spent more than a year meeting with community stakeholders and using their feedback to make significant changes to its grid improvement plan.

This year, the North Carolina Utilities Commission finally approved a set of grid improvements that will cost customers $1.2 billion. But the commission reserved the right to deny Duke reimbursement of those costs if it cannot prove they are prudent and reasonable. The commission’s general counsel, Sam Watson, declined to discuss the decision, saying the commission can comment on specific cases only in public orders.

The utility is now burying power lines in “several neighborhoods across the state” that are most vulnerable to wide-scale outages, Brooks said. It is also fitting aboveground power lines with “self-healing” technology, a network of sensors that diverts electricity away from equipment failures to minimize the number of customers affected by an outage.

As part of a settlement with Vote Solar, Duke Energy last year agreed to work with state officials and local leaders to further evaluate the potential impacts of climate change, a process that Brooks said is expected to take two to three years.

High costs create hurdles
The debate in North Carolina is being echoed in states across the nation, where burying power lines has emerged as one of the most common proposals for insulating the grid from high winds, fires and flooding. But opponents have balked at the cost, which can run in the millions of dollars per mile.

In California, for example, Pacific Gas & Electric wants to bury 10,000 miles of power lines, both to make the grid more resilient and to reduce the risk of sparking wildfires. Its power equipment has contributed to multiple deadly wildfires in the past decade, including the 2018 Camp Fire that killed at least 85 people.

PG&E’s proposal has drawn scorn from critics, including San Jose Mayor Sam Liccardo, who say it would be too slow and expensive. But Patricia Poppe, the company’s CEO, told reporters that doing nothing would cost California even more in lost lives and property while struggling to keep the lights on during wildfires. The plan has yet to be submitted to the state, but Terrie Prosper, a spokeswoman for the California Public Utilities Commission, said the commission has supported underground lines as a wildfire mitigation strategy.

Another oft-floated solution is microgrids, small electrical systems that provide power to a single neighborhood, university or medical center. Most of the time, they are connected to a larger utility system. But in the event of an outage, microgrids can operate on their own, with the aid of solar energy stored in batteries.

In Florida, regulators recently approved a four-year microgrid pilot project, but the technology remains expensive and unproven. In Maryland, regulators in 2016 rejected a plan to spend about $16 million for two microgrids in Baltimore, in part because the local utility made no attempt to quantify “the tangible benefits to its customer base.”

Amid shut-off woes, a beacon of energy

In Texas, where officials have largely abandoned state regulation in favor of the free market, the results have been no more encouraging. Without requirements, as exist elsewhere, for building extra capacity for times of high demand or stress, the state was ill-equipped to handle an abnormal deep freeze in February that knocked out power to 4 million customers for days.

Since then, Berkshire Hathaway Energy and Starwood Energy Group each proposed spending $8 billion to build new power plants to provide backup capacity, with guaranteed returns on the investment of 9 percent, but the Texas legislature has not acted on either plan.

New York is one of the few states where regulators have assessed the risks of climate change and pushed utilities to invest in solutions. After 800,000 New Yorkers lost power for 10 days in 2012 in the wake of Hurricane Sandy, state regulators ordered utility giant Con Edison to evaluate the state’s vulnerability to weather events.

The resulting report, which estimated climate risks could cost the company as much as $5.2 billion by 2050, gave ConEd data to inform its investments in storm hardening measures, including new storm walls and submersible equipment in areas at risk of flooding.

Meanwhile, the New York Public Service Commission has aggressively enforced requirements that utility companies keep the lights on during big storms, fining utility providers nearly $190 million for violations including inadequate staffing during Tropical Storm Isaias in 2020.

“At the end of the day, we do not want New Yorkers to be at the mercy of outdated infrastructure,” said Rory M. Christian, who last month was appointed chair of the New York commission.

The price of inaction
In North Carolina, as Duke Energy slowly works to harden the grid, some are pursuing other means of fostering climate-resilient communities.

Beth Schrader, the recovery and resilience director for New Hanover County, which includes Wilmington, said some of the people who went the longest without power after Florence had no vehicles, no access to nearby grocery stores and no means of getting to relief centers set up around the city.

For example, Quanesha Mullins, a 37-year-old mother of three, went eight days without power in her housing project on Wilmington’s east side. Her family got by on food from the Red Cross and walked a mile to charge their phones at McDonald’s. With no air conditioning, they slept with the windows open in a neighborhood with a history of violent crime.

Schrader is working with researchers at the University of North Carolina in Charlotte to estimate the cost of helping people like Mullins. The researchers estimate that it would have cost about $572,000 to provide shelter, meals and emergency food stamp benefits to 100 families for two weeks, said Robert Cox, an engineering professor who researches power systems at UNC-Charlotte.

Such calculations could help spur local governments to do more to help vulnerable communities, for example by providing “resilience outposts” with backup power generators, heating or cooling rooms, Internet access and other resources, Schrader said. But they also are intended to show the costs of failing to shore up the grid.

“The regulators need to be moved along,” Cox said.

In the meantime, Tonye Gray finds herself worrying about what happens when the next storm hits. While Duke Energy says it is burying power lines in the most outage-prone areas, she has yet to see its yellow-vested crews turn up in her neighborhood.

“We feel,” she said, “that we’re at the end of the line.”

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Smart Meter Texas real-time pricing faces rollback as utilities limit on-demand reads, impacting demand response, home area networks, ERCOT wholesale tracking, and thermostat automation, reducing efficiency gains promised through deregulation and smart meter investments.

Key Points

A plan linking smart meters to ERCOT prices, enabling near real-time usage alignment and automated demand response.

✅ Twice-hourly reads miss 15-minute ERCOT price spikes.

✅ Less than 1% of 7.3M meters use HAN real-time features.

✅ Limits hinder automation for HVAC, EV charging, and pool pumps.

Utilities made a promise several years ago when they built Smart Meter Texas that they’d come up with a way for consumers to monitor their electricity use in real time. But now they’re backing out of the deal with the approval of state regulators, leaving in the lurch retail power companies that are building their business model on the promise of real time pricing and denying consumers another option for managing their electricity costs.

Texas utilities collected higher rates to finance the building of a statewide smart meter network that would allow customers to track their electricity use and the quickly changing prices on wholesale power markets almost as they happened. Some retailers are building electricity plans around this promise, providing customers with in-home devices that would eventually track pricing minute-by-minute and allow them to automatically turn down or shut off air conditioners, pool pumps and energy sucking appliances when prices spiked on hot summer afternoons and turn them back on when they prices fell again.

The idea is to help save consumers money by allowing them to shift their electricity consumption to periods when power is cheaper, typically nights and weekends, even as utility revenue in a free-power era remains a debated topic.

“We’re throwing away a large part of (what) ratepayers paid for,” said John Werner, CEO of GridPlus Texas, one of the companies offering consumers a real-time pricing plan that is scheduled to begin testing next month. “They made the smart meters dumb meters.”

When Smart Meter Texas was launched a decade ago by a consortium of the state’s biggest utilities, it was considered an important part of deregulation. The competitive market for electricity held the promise that consumers would eventually have the technology to control their electricity use through a home area network and cut their power bills.

Regulators and legislators also were enticed by the possibility of making the electric system more efficient and relieving pressure on the power grid as consumers responded to high prices and cut consumption when temperatures soared, with ongoing discussions about Texas grid reliability informing policy choices.

One study found that smart meters coupled with smart real time consumption monitors could reduce electricity use between 3 percent and 5 percent, according to Call Me Power, a website sponsored by the European electricity price shopping service Selectra.

But utilities complained that the home area network devices were expensive to install and not used very often, and, with flat electricity demand weighing on growth, they questioned further investment. CenterPoint manager Esther Floyd Kent filed an affidavit with the commission in May that it costs the utility about $30,000 annually to support the network devices, plus maintenance.

Over a six-year period, CenterPoint paid $124,500, or about $20,000 a year, to maintain the system. As of April, there were only 4,067 network devices in CenterPoint’s service area, meaning the utility pays about $30.70 each year to maintain each device.

Centerpoint last year generated $9.6 billion in revenues and earned a $1.8 billion profit, according to its financial filings. CenterPoint officials did not respond to requests for comment.

Other utilities that are part of the Smart Meter consortium also complained to the Public Utility Commission that, up to now, the system hasn’t developed. All told, Texas has 7.3 million meters connected to Smart Meter Texas, but less than 1 percent are using the networking functions to track real-time prices and consumption, according to the testimony of Donny R. Helm, director of technology strategy and architecture for the state’s largest utility Oncor Electric Delivery Co. in Dallas.

The isssue was resolved recently through a settlement agreement that limits on-demand readings to twice an hour that Smart Meter Texas must provide customers. The price of power changes every 15 minutes, so a twice an hour reading may miss some price spikes.

The Public Utility Commission signed off on the deal, and so did several other groups including several retail electricity providers and the Office of Public Utility Counsel which represents residential customers and small businesses.

Michele Gregg, spokeswoman for the Public Utility Counsel, testified in December that the consumer advocate supported the change because widespread use of the networks never materialized. Catherine Webking, an Austin lawyer who represents the Texas Energy Association for Marketers, a group of retail electric providers, said she believes the deal was a reasonable resolution of providing the benefits of Smart Meter Texas while not incurring too much cost.

But Griddy, an electricity provider that offers customers the opportunity to pay wholesale power prices, which also issued a plea to customers during a price surge, said the state hasn’t given the smart-meter networks a chance and could miss out on its potential. Griddy was counting on the continued adoption of real time pricing as the next step for customers wanting to control their electricity costs.

Right now, Griddy sends out price alerts from the grid operator Electric Reliability Council of Texas so businesses like hotels can run washers and dryers when electricity prices are cheapest. But the company was counting on a smart-meter program that would allow customers to track wholesale prices and manage consumption themselves, making Griddy’s offerings attractive to more people.

Wholesale prices are generally cheaper than retail prices, but they can fluctuate widely, especially when the Texas power grid faces another crisis during extreme weather. Last year, wholesale prices averaged less than 3 cents per kilowatt hour, much lower than than retail rates that now are running above 11 cents, but they can spike at times of high demand to as much as $9 a kilowatt hour.

What customers want is to be able to use energy when it’s cheapest, said Greg Craig, Griddy’s CEO, and they want to do it automatically. They want to be able to program their thermostat so that if the price rises they can shut off their air conditioning and if the price falls, they can charge their electric-powered vehicle.

Griddy customers may still save money even without real time data, he said. But they won’t be able to see their usage in real time or see how much they’re spending.

“The big utilities have big investments in the existing way and going to real time and more transparency isn’t really in their best interest,” said Craig.

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Sub-Saharan Africa Energy Access faces critical deficits; SDG7, clean energy finance, off-grid solar, and microgrids drive electrification for health, education, and economy amid World Bank and IEA efforts to expand reliable, affordable power.

Key Points

Reliable, affordable power in sub-Saharan Africa via renewables, off-grid solar, and SDG7-led electrification.

✅ SDG7 targets universal, modern energy access by 2030

✅ Off-grid solar and microgrids boost rural electrification

✅ Health, education, and business depend on reliable power

Sub-Saharan Africa has an electricity problem. While the world as a whole has made great strides when it comes to providing access to electricity and moving toward universal electricity access worldwide (the world average is now 90 per cent with access, up from 83 per cent in 2010), southern and western African states still lag far behind.

According to Tracking SDG7: The Energy Progress Report, produced by a consortium of organisations including the World Bank, the International Energy Agency and the World Health Organization, 759 million people were without electricity in 2019 and threequarters of them were based in sub-Saharan Africa. At just seven per cent, South Sudan had the lowest access figures; Chad, Burundi and Malawi were only marginally higher. What’s more, due to a combination of factors, the situation is getting worse. In total, the region’s access deficit increased from 556 million people in 2010 to 570 million people in 2019.

These days, being without electricity has an impact on every sphere of life. The Covid-19 pandemic only served to put this into sharper relief. Intermittent electricity meant vaccination doses that rely on cold storage were impossible to deliver and, as more than 70 per cent of the health facilities in sub-Saharan Africa have no access to reliable electricity, the problem was vast. But even without a global pandemic, having no power stymies opportunity in every field, from education to economics.

French photojournalist Pascal Maitre, who has spent much of his career writing about sub-Saharan Africa, wanted to document the problems faced by people in areas with no electricity. He thought particularly carefully about the location for his project. ‘First, I was thinking I could take images in the Democratic Republic of the Congo,’ he says. ‘But then I thought that if you chose a place that has war, it’s logical that electricity won’t really work. So, instead, I wanted to find a place that is quite stable. I decided to go to Benin, where they have a democracy. It is a good example of a country that’s not in really bad shape but where they still have this problem. Also, I didn’t want to go to a place that is very remote, where it is normal not to have good service. So I decided to go to a place around 50 kilometres from the capital that you can get to by road.’

Maitre visited several villages in the region, as well as making trips to Chad and Senegal, and encountered the full range of limitations engendered by the power shortage. From teachers struggling to conduct lessons in the dark to midwives forced to work with only the weak light from a phone, the situation was clearly unacceptable. ‘People were very, very, very upset,’ he says. ‘I conducted a lot of interviews in different villages and lack of electricity touches education, economy, business, security and also emigration, because people have to move to big cities or maybe to Europe to get jobs.’

Where once the situation might have been accepted as the norm, people today are fully aware of the ways in which they are held back by the lack of power. As Maitre remembers: ‘A guy said to me one day, “Do you think it is normal that last time my wife delivered a baby, the midwife had to hold her phone between her teeth in order to see what she was doing?” You feel very frustrated.’ He adds that the fact that most people now have mobile phones only highlights the hardship. ‘Before, maybe it was not so frustrating. But now, most of these people have cellphones. The cellphone company puts antennae everywhere so the phones work, but people cannot recharge their phones. They have to go to the market, where someone will come with a generator to recharge.’

Governments and global organisations are very aware of the problem across the world as a whole. Sustainable Development Goal 7 (SDG7) – one of the 17 goals set out in 2015 by the United Nations General Assembly – was designed to ensure universal access to affordable, reliable, sustainable and modern energy by 2030, underscoring the push for clean, affordable and sustainable electricity for all by 2030. As part of this goal, international financial flows to developing countries in support of clean energy reached US$17 billion in 2018. As a result, some areas have seen huge improvement. According to the Energy Progress Report, in Latin America and the Caribbean, and in Eastern and South-Eastern Asia, the advance of electrification has been enough to approach universal access. By 2019, in Western Asia and North Africa, and Central and South Asia, 94 and 95 per cent of the population respectively had access to electricity.

But these statistics only serve to emphasise just how bad the situation is in sub-Saharan Africa, where electricity systems are unlikely to go green this decade according to several analyses. As the report states: ‘While renewable energy has demonstrated remarkable resilience during the pandemic, the unfortunate fact is that gains in energy access throughout Africa are being reversed: the number of people lacking access to electricity is set to increase in 2020, making basic electricity services unaffordable for up to 30 million people who had previously enjoyed access.’

The small silver lining is that if the situation is dealt with properly, the region could build a renewable-energy system from the ground up, rather than having to undergo the costly and complex transitions underway in developed countries. In rural areas, small-scale or off-grid renewable systems (mostly solar) are expected to play an important role, as highlighted by a recent IRENA report on decarbonisation, in increasing access. In fact, solar panels are already used in many areas. In 2019, 105 million people had access to off-grid solar solutions, up from 85 million in 2016, and almost half lived in sub-Saharan Africa, with 17 million in Kenya and eight million in Ethiopia.

Rachel Kyte is currently serving as the 14th dean of the Fletcher School at Tufts University in the USA, but her CV is long. She was previously CEO of the UN-affiliated Sustainable Energy for All (SeforALL), as well as the World Bank Group vice president and special envoy for climate change, leading the run-up to the Paris Agreement. According to her, a focus on renewables is absolutely essential, both for wider efforts to tackle climate change, with some advocating a fossil fuel lockdown to drive a climate revolution, but also for the people of sub-Saharan Africa. ‘The fossil fuel industry has said it will just extend the centralised fossil-fuel power systems that we have today to reach these people,’ she says.

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Nighttime thermoradiative power converts outgoing infrared radiation into electricity using semiconductor photodiodes, leveraging negative illumination and sky cooling to harvest renewable energy from Earth-to-space heat flow when solar panels rest, regardless of weather.

Key Points

Nighttime thermoradiative power converts Earth's outgoing infrared heat into electricity using semiconductor diodes.

✅ Uses negative illumination to tap Earth-to-space heat flow

✅ Infrared semiconductor photodiodes generate small nighttime current

✅ Theoretical output ~4 W/m^2; lab demo reached 64 nW/m^2

There's a stark contrast between the freezing temperatures of space and the relatively balmy atmosphere of Earth, and that contrast could help generate electricity, scientists say – and alongside concepts such as space-based solar power, utilizing the same optoelectronic physics used in solar panels. The obvious difference this would have compared with solar energy is that it would work during the night time, a potential source of renewable power that could keep on going round the clock and regardless of weather conditions.

Solar panels are basically large-scale photodiodes - devices made out of a semiconducting material that converts the photons (light particles) coming from the Sun into electricity by exciting electrons in a material such as silicon, while concepts like space solar beaming could complement them during adverse weather.

In this experiment, the photodiodes work 'backwards': as photons in the form of infrared radiation - also known as heat radiation - leave the system, a small amount of energy is produced, similar to how raindrop electricity harvesting taps ambient fluxes in other experiments.

This way, the experimental system takes advantage of what researchers call the "negative illumination effect" – that is, the flow of outgoing radiation as heat escapes from Earth back into space. The setup explained in the new study uses an infrared semiconductor facing into the sky to convert this flow into electrical current.

"The vastness of the Universe is a thermodynamic resource," says one of the researchers, Shanhui Fan from Stanford University in California.

"In terms of optoelectronic physics, there is really this very beautiful symmetry between harvesting incoming radiation and harvesting outgoing radiation."

It's an interesting follow-up to a research project Fan participated in last year: a solar panel that can capture sunlight while also allowing excess heat in the form of infrared radiation to escape into space.

In the new study, this "energy harvesting from the sky" process can produce a measurable amount of electricity, the researchers have shown – though for the time being it's a long way from being efficient enough to contribute to our power grids, but advances in peer-to-peer energy sharing could still make niche deployments valuable.

In the team's experiments they were able to produce 64 nanowatts per square metre (10.8 square feet) of power – only a trickle, but an amazing proof of concept nevertheless. In theory, the right materials and conditions could produce a million times more than that, and analyses of cheap abundant electricity show how rapidly such advances compound, reaching about 4 watts per square metre.

"The amount of power that we can generate with this experiment, at the moment, is far below what the theoretical limit is," says one of the team, Masashi Ono from Stanford.

When you consider today's solar panels are able to generate up to 100-200 watts per square metre, and in China solar is cheaper than grid power across every city, this is obviously a long way behind. Even in its earliest form, though, it could be helpful for keeping low-power devices and machines running at night: not every renewable energy device needs to power up a city.

Now that the researchers have proved this can work, the challenge is to improve the performance of the experimental device. If it continues to show promise, the same idea could be applied to capture energy from waste heat given off by machinery, and results in humidity-powered generation suggest ambient sources are plentiful.

"Such a demonstration of direct power generation of a diode facing the sky has not been previously reported," explain the researchers in their published paper.

"Our results point to a pathway for energy harvesting during the night time directly using the coldness of outer space."

The research has been published in Applied Physics Letters.

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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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TVA Rates and Renewable Energy Scrutiny spotlights electricity rates, distributed energy resources, solar and wind deployment, natural gas plans, grid access charges, energy efficiency cuts, and House oversight of lobbying, FERC inquiries, and least-cost planning.

Key Points

A congressional probe into TVA pricing and practices affecting renewables, energy efficiency, and climate goals.

✅ House panel probes TVA rates, DER and solar policies.

✅ Efficiency programs cut; least-cost planning questioned.

✅ Inquiry on lobbying, hidden fees; FERC scrutiny.

The Tennessee Valley Authority is facing federal scrutiny about its electricity rates and climate action, amid ongoing debates over network profits in other markets.

Members of the House Committee on Energy and Commerce are “requesting information” from TVA about its ratepayer bills and “out of concern” that TVA is interfering with the deployment of renewable and distributed energy resources, even as companies such as Tesla explore electricity retail to expand customer options.

“The Committee is concerned that TVA’s business practices are inconsistent with these statutory requirements to the disadvantage of TVA’s ratepayers and the environment,” the committee said in a letter to TVA CEO Jeffrey Lyash.

The four committee members — U.S. Reps. Frank Pallone, Jr. (D-NJ), Bobby L. Rush (D-IL), Diana DeGette (D-CO), and Paul Tonko (D-NY) — suggested that Tennessee Valley residents pay too much for electricity despite TVA’s relatively low rates, even as regulators have, in other cases, scrutinized mergers like the Hydro One-Avista deal to safeguard ratepayers, underscoring similar concerns. In 2020, Tennessee residents had electric bills higher than the national average, while low-income residents in Memphis have historically faced one of the highest energy burdens in the U.S.

In 2018, TVA reduced its wholesale rate while adding a grid access charge on local power companies—and interfered with the adoption of solar energy. Internal TVA documents obtained through a Freedom of Information Act request by the Energy and Policy Institute revealed that TVA permitted local power companies to impose new fees on distributed solar generation to “lessen the potential decrease in TVA load that may occur through the adoption of [behind the meter] generation.”

Additionally, the committee said TVA is not prioritizing energy conservation and efficiency or “least-cost planning” that includes renewables, as seen in oversight such as the OEB's Hydro One rates decision emphasizing cost allocation. TVA reduced its energy efficiency programs by nearly two-thirds between 2014 and 2018 and cut its energy efficiency customer incentive programs.

At this time, TVA has not aligned its long-term planning with the Biden administration’s goal to achieve a carbon-free electricity sector by 2035. TVA’s generation mix, which is roughly 60% carbon-free, comprises 39% nuclear, 19% coal, 26% natural gas, 11% hydro, 3% wind and solar, and 1% energy efficiency programs, according to TVA.

The committee is “greatly concerned that TVA has invested comparatively little to date in deploying solar and wind energy, while at the same time considering investments in new natural gas generation.”

TVA has announced plans to shutter the Kingston and Cumberland coal plants and is evaluating whether to replace this generation with natural gas, which is a fossil fuel, while debates over grid privatization raise questions about consumer benefits. TVA’s coal and natural gas plants represent most of the largest sources of greenhouses emissions in Tennessee.

TVA responded with a statement without directly addressing the committee’s concerns. TVA said its “developing and implementing emerging technologies to drive toward net-zero emissions by 2050.”

The final question that the House committee posed is whether TVA is funding any political activity. In 2019, the committee questioned TVA about its membership to the now-disbanded Utility Air Regulatory Group, a coalition that was involved in over 200 lawsuits that primarily fought Clear Air Act regulations.

TVA revealed that it had contributed $7.3 million to the industry lobbying group since 2001. Since TVA doesn’t have shareholders, customers paid for UARG membership fees, echoing findings that deferred utility costs burden customers in other jurisdictions. An Office of the Inspector General investigation couldn’t prove whether TVA’s contributions directly funded litigation because UARG didn’t have a line-by-line accounting of what they did with TVA’s dollars.

The congressional committee questioned whether TVA is still paying for lobbying or litigation that opposes “public health and welfare regulations.”

This last question follows a recent trend of questioning utilities about “hidden fees.” In December, the Federal Energy Regulatory Commission issued a Notice of Inquiry to examine how bills from investor-owned utilities might contain fees that fund political activity, and regulators have penalized firms like NT Power over customer notice practices, highlighting consumer protection. The Center for Biological Diversity filed a petition to protect electric and gas customers of investor-owned utilities from paying these fees, which may be used for lobbying, campaign-related donations and litigation.

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