Canadian Solar moves HQ to Kitchener

Texas Power Grid Crisis strains ERCOT as extreme cold, ice storms, and heavy snow trigger rolling blackouts, load shedding, and boil-water notices, leaving millions without electricity while frozen turbines and low gas pressure hinder generation.

Key Points

A statewide emergency of outages and boil-water notices as ERCOT battles extreme cold and load shedding.

✅ Millions without power; ERCOT orders load shedding

✅ Boil-water notices in Austin, Houston, Fort Worth

✅ Frozen equipment, low gas pressure, extreme cold disrupt supply

Nearly 3 million homes and businesses in Texas remain without power, some for a third consecutive day, as severe winter weather continues to pummel the state, forcing some localities to issue boil-water notices and urge residents to reduce their electricity usage.

Heavy snowfall, ice storms and bitter temperatures continue to put an enormous strain on the state's power grid. This as the Electric Reliability Council of Texas (ERCOT), which manages roughly 75% of the Texas power grid, announced Wednesday morning that some 600,000 households had power restored overnight.

That still left another 2.7 million customers having to endure extreme cold with no indication of when the thaw would break in their homes.

"We know millions of people are suffering," ERCOT's president and CEO, Bill Magness, said in a statement Wednesday. "We have no other priority than getting them electricity. No other priority."

ERCOT also said Wednesday that it was urging local utilities to shed some 14,000 megawatts of load, which translates to roughly 2.8 million customers, to prepare for a sudden increase in demand.

"The ability to restore more power is contingent on more generation coming back online," said Dan Woodfin, the senior director of ERCOT's system operations, and utility supply-chain constraints can further complicate repair timelines for some utilities.

He said that about 185 generating units were offline, stemming from a range of factors including frozen wind turbines, low gas pressure and frozen instrumentation.

But many Texans feel abandoned by the council and power companies and they are lashing out at the local face of utilities.

The City of Austin's community-owned electric utility, Austin Energy, issued a tweet saying crews that are working to restore power are facing harassment.

"Our crews have been working 24/7 and in these elements," Austin Energy announced. "Some of our crews are reporting incidents of harassment, threatening them and even throwing things at them."

Officials pleaded with the public to remain calm. "I know people are extremely frustrated. But please, I bet of you, do not approach AE crews."

Parts of Austin are under a boil water notice, which Austin Water Director Greg Meszaros attempted to explain during a press briefing Wednesday afternoon.

"There was a large main break in that area, maybe multiple ones. We're seeing main breaks and pipes bursting by the tens of thousands. Our entire system is under stress," Meszaros said.

It's not just the Lone Star State that is being crippled by the arctic blast, with a deep freeze slamming the energy sector across the country.

At least two dozen people have died this week from weather-related incidents, according to The Associated Press.

The National Weather Service reports that more than 100 million Americans are being affected by extreme winter weather from the south central U.S. to the East Coast, including Arkansas, Louisiana, Mississippi, North Carolina, Virginia and West Virginia, and analysts warn of blackout risks nationwide during extreme heat as well.

The National Weather Service adds that cold temperatures over the nation's heartland will begin to "moderate in the coming days" but that many parts will remain 20 to 35 degrees below normal in the Great Plains, Mississippi Valley and lower Great Lakes region.

"Potential is increasing for significant icing across portions of the Mid-Atlantic, which will be very impactful, especially for those hardest hit from the previous ice storm," the National Weather Service tweeted Wednesday.

Texas Gov. Greg Abbott railed against ERCOT, and Elon Musk criticized the agency as unreliable, saying the utility "has been anything but reliable over the past 48 hours."

"This is unacceptable," Abbott added, as residents were facing rotating intentional power outages. The governor issued an executive order that will add reforms for how the power grid is managed, including grid reliability improvements under discussion, as an emergency legislative item for the state legislature to review.

The rolling power outages forced Fort Worth to extend a boil-water notice for roughly 212,000 residents. Officials said the outages affected the city's systems that both treat water and move it to customers.

Fort Worth officials said nine other localities that purchase water from the city are also affected, including Haslet, Keller, Lake Worth and Northlake.

Officials in Houston also issued a boil-water notice for the city's residents Wednesday.

"Do not drink the water without boiling it first," Houston Public Works said from its official Twitter account. "Bring all water to a boil for at least two minutes. Let it cool before using."

In Harris County, which includes Houston, Judge Lina Hidalgo warned residents about extended power outages.

"Let me give it to you straight, based on the visibility I have: Whether you have power or not right now, there is a possibility of power outages even beyond the length of this weather," Hidalgo said, according to Houston Public Media.

The NPR member station adds that county officials have also reported more than 300 cases of carbon monoxide poisoning since Monday as residents going without electricity search desperately for alternative sources of warmth.

"In no uncertain terms, this is a public health disaster and a public health emergency," Samuel Prater, an emergency physician at Memorial Hermann-Texas Medical Center, said at a news briefing Tuesday.

Prater warned residents that over the last 24 hours, emergency officials "have seen a striking increase in the number of cases related to improper heating sources," including indoor use of generators, charcoal grills, campfire stoves and other devices that are being used to warm homes. The result, he added, is carbon monoxide poisoning of entire families.

"If you think you or a loved one has become ill from carbon monoxide poisoning, first thing you need to do is get outside to fresh air," Prater said.

A woman and an 8-year-old girl are among those who have reportedly died from carbon monoxide poisoning after a vehicle was left running inside a garage in an attempt to generate heat, according to Houston's ABC affiliate.

As Texas endures further weather-related issues, including road and highway closures, there's a renewed focus on how the Texas power grid has failed, and why the grid is facing another crisis amid this prolonged cold.

The Texas electrical grid is "facing conditions that it was not designed for," said Emily Grubert, a professor at Georgia Tech whose expertise includes electric networks.

"These are really extreme conditions for the Texas grid. It's very cold. It's cold across the entire state, and it's cold for a long time. This does not happen very often," she said in an interview with NPR's Morning Edition.

"Demand really spiked both in the electricity and the natural gas systems at the same time as a lot of the generators were not able to operate because of those cold conditions, and not being prepared for it is really what's going on," Grubert said. "But a lot of grids are susceptible to really, really major failures when they are this far outside of design conditions."

Abbott told Fox News on Tuesday that with weather-related shutdowns in wind and solar energy, which account for more than 10% of the state's grid, renewable energy is partly to blame for the Texas power crisis, even as he later touted the grid's readiness heading into the fall.

"It just shows that fossil fuel is necessary for the state of Texas as well as other states to make sure that we'll be able to heat our homes in the wintertime and cool our homes in the summertime," Abbott said.

But Grubert said that "coal, gas and nuclear actually shut down because of the extreme cold due to things like instruments freezing, et cetera. So I think the overall point here is all of the fuels were really, really struggling."

Related News

• Electricity Forum News

• Energy Policy News

Costa Rica Renewable Energy Record highlights 99.99% clean power in May 2019, driven by hydropower, wind, solar, geothermal, and biomass, enabling ICE REM electricity exports and reduced rates from optimized generation totaling 984.19 GWh.

Key Points

May 2019 benchmark: Costa Rica generated 99.99% of 984.19 GWh from renewables, shifting from imports to regional exports.

✅ 99.99% renewable share across hydro, wind, solar, geothermal, biomass

✅ 984.19 GWh generated; ICE suspended imports and exported via REM

✅ Geothermal output increased to offset dry-season hydropower variability

During the whole month of May 2019, Costa Rica generated a total of 984.19 gigawatt hours of electricity, the highest in the country’s history. What makes this feat even more impressive is the fact that 99.99% of this energy came from a portfolio of renewable sources such as hydropower, wind, biomass, solar, and geothermal.

With such a high generation rate, the state power company Instituto Costariccense de Electricidad (ICE) were able to suspend energy imports from the first week of May and shifted to exports, while U.S. renewable electricity surpassed coal in 2022 domestically. To date, the power company continues to sell electricity to the Regional Electricity Market (REM) which generates revenues and is likely to reduce local electricity rates, a trend echoed in places like Idaho where a vast majority of electricity comes from renewables.

The record-breaking power generation was made possible by optimization of the country’s renewable sources, much as U.S. wind capacity surpassed hydro capacity at the end of 2016 to reshape portfolios. As the period coincided with the tail end of the dry season, the geothermal quota had to be increased.

Costa Rica remains a leader in renewable power generation, whereas U.S. wind generation has become the most-used renewable source in recent years. In 2015, more than 98% of the country’s electrical generation came from renewable sources, while U.S. renewables hit a record 28% in April in one recent benchmark. Through the years, this figure has remained fairly constant despite dry bouts caused by the El Niño phenomenon, and U.S. solar generation also continued to rise.

Related News

• Electricity Forum News

• Renewable Energy News

Electric Buses reduce urban emissions and noise, but require charging infrastructure, grid upgrades, and depot redesigns; they offer lower operating costs and simpler maintenance, with range limits influencing routes, schedules, and on-route fast charging.

Key Points

Battery-electric buses cut emissions and noise while lowering operating and maintenance costs for transit agencies.

✅ Lower emissions, noise; improved rider experience

✅ Requires charging, grid upgrades, depot redesigns

✅ Range limits affect routes; on-route fast charging helps

In lots of ways, the electric bus feels like a technology whose time has come. Transportation is responsible for about a quarter of global emissions, and those emissions are growing faster than in any other sector. While buses are just a small slice of the worldwide vehicle fleet, they have an outsize effect on the environment. That’s partly because they’re so dirty—one Bogotá bus fleet made up just 5 percent of the city’s total vehicles, but a quarter of its CO2, 40 percent of nitrogen oxide, and more than half of all its particulate matter vehicle emissions. And because buses operate exactly where the people are concentrated, we feel the effects that much more acutely.

Enter the electric bus. Depending on the “cleanliness” of the electric grid into which they’re plugged, e-buses are much better for the environment. They’re also just straight up nicer to be around: less vibration, less noise, zero exhaust. Plus, in the long term, e-buses have lower operating costs, and related efforts like US school bus electrification are gathering pace too.

So it makes sense that global e-bus sales increased by 32 percent last year, according to a report from Bloomberg New Energy Finance, as the age of electric cars accelerates across markets worldwide. “You look across the electrification of cars, trucks—it’s buses that are leading this revolution,” says David Warren, the director of sustainable transportation at bus manufacturer New Flyer.

Today, about 17 percent of the world’s buses are electric—425,000 in total. But 99 percent of them are in China, where a national mandate promotes all sorts of electric vehicles. In North America, a few cities have bought a few electric buses, or at least run limited pilots, to test the concept out, and early deployments like Edmonton's first e-bus offer useful lessons as systems ramp up. California has even mandated that by 2029 all buses purchased by its mass transit agencies be zero-emission.

But given all the benefits of e-buses, why aren’t there more? And why aren’t they everywhere?

“We want to be responsive, we want to be innovative, we want to pilot new technologies and we’re committed to doing so as an agency,” says Becky Collins, the manager of corporate initiative at the Southeastern Pennsylvania Transportation Authority, which is currently on its second e-bus pilot program. “But if the diesel bus was a first-generation car phone, we’re verging on smartphone territory right now. It’s not as simple as just flipping a switch.”

One reason is trepidation about the actual electric vehicle. Some of the major bus manufacturers are still getting over their skis, production-wise. During early tests in places like Belo Horizonte, Brazil, e-buses had trouble getting over steep hills with full passenger loads. Albuquerque, New Mexico, canceled a 15-bus deal with the Chinese manufacturer BYD after finding equipment problems during testing. (The city also sued). Today’s buses get around 225 miles per charge, depending on topography and weather conditions, which means they have to re-up about once a day on a shorter route in a dense city. That’s an issue in a lot of places.

If you want to buy an electric bus, you need to buy into an entire electric bus system. The vehicle is just the start.

The number one thing people seem to forget about electric buses is that they need to get charged, and emerging projects such as a bus depot charging hub illustrate how infrastructure can scale. “We talk to many different organizations that get so fixated on the vehicles,” says Camron Gorguinpour, the global senior manager for the electric vehicles at the World Resources Institute, a research organization, which last month released twin reports on electric bus adoption. “The actual charging stations get lost in the mix.”

But charging stations are expensive—about $50,000 for your standard depot-based one. On-route charging stations, an appealing option for longer bus routes, can be two or three times that. And that’s not even counting construction costs. Or the cost of new land: In densely packed urban centers, movements inside bus depots can be tightly orchestrated to accommodate parking and fueling. New electric bus infrastructure means rethinking limited space, and operators can look to Toronto's TTC e-bus fleet for practical lessons on depot design. And it’s a particular pain when agencies are transitioning between diesel and electric buses. “The big issue is just maintaining two sets of fueling infrastructure,” says Hanjiro Ambrose, a doctoral student at UC Davis who studies transportation technology and policy.

“We talk to many different organizations that get so fixated on the vehicles. The actual charging stations get lost in the mix as the American EV boom gathers pace across sectors.”

Then agencies also have to get the actual electricity to their charging stations. This involves lengthy conversations with utilities about grid upgrades, rethinking how systems are wired, occasionally building new substations, and, sometimes, cutting deals on electric output, since electric truck fleets will also strain power systems in parallel. Because an entirely electrified bus fleet? It’s a lot to charge. Warren, the New Flyer executive, estimates it could take 150 megawatt-hours of electricity to keep a 300-bus depot charged up throughout the day. Your typical American household, by contrast, consumes 7 percent of that—per year. “That’s a lot of work by the utility company,” says Warren.

For cities outside of China—many of them still testing out electric buses and figuring out how they fit into their larger fleets—learning about what it takes to run one is part of the process. This, of course, takes money. It also takes time. Optimists say e-buses are more of a question of when than if. Bloomberg New Energy Finance projects that just under 60 percent of all fleet buses will be electric by 2040, compared to under 40 percent of commercial vans and 30 percent of passenger vehicles.

Which means, of course, that the work has just started. “With new technology, it always feels great when it shows up,” says Ambrose. “You really hope that first mile is beautiful, because the shine will come off. That’s always true.”

Related News

• Electricity Forum News

• EV Infrastructure News

Alberta Energy-Only Electricity Market faces capacity market debate, AESO price cap review, and coal-to-gas shifts by TransAlta and Capital Power, balancing reliability with volatility as investment signals evolve across Alberta's grid.

Key Points

An energy market paying generators only for electricity sold, with AESO oversight and a price cap guiding new capacity.

✅ AESO reviewing $999 per MW-h wholesale price cap.

✅ UCP retained energy-only; capacity market plan cancelled.

✅ TransAlta and Capital Power shift to coal-to-gas.

The Kenney government’s decision to cancel the redesign of Alberta’s electricity system to a capacity market won’t side-track two of the province’s largest power generators from converting coal-fired facilities to burn natural gas as part of Alberta’s shift from coal to cleaner energy overall.

But other changes could be coming to the province’s existing energy-only electricity market — including the alteration of the $999 per megawatt-hour (MW-h) wholesale price cap in Alberta.

The heads of TransAlta Corp. and Capital Power Corp. are proceeding with strategies to convert existing coal-fired power generating facilities to use natural gas in the coming years.

Calgary-based TransAlta first announced in 2017 that it would make the switch, as the NDP government was in the midst of overhauling the electricity sector and wind generation began to outpace coal in the province.

At the time, the Notley government planned to phase out coal-fired power by 2030, even as Alberta moved to retire coal by 2023 in practice, and shift Alberta into an electricity capacity market in 2021.

Such a move, made on the recommendation of the Alberta Electric System Operator (AESO), was intended to reduce price volatility and ensure system reliability.

Under the energy-only market, generators receive payments for electricity produced and sold into the grid. In a capacity market, generators are also paid for having power available on demand, regardless of how often they sell energy into the provincial grid.

The UCP government decided last month to ditch plans for a capacity market after consulting with the sector, saying it would be better for consumers.

On a conference call, TransAlta CEO Dawn Farrell said the company will convert coal-fired generating plants to burn gas, although it may alter the mix between simple conversions and switching to so-called “hybrid” plants.

(A hybrid conversion is a larger and more-expensive switch, as it includes installing a new gas turbine and heat-recovery steam generator, but it creates a highly efficient combined cycle unit.)

“Our view is fundamentally that carbon will be priced over the next 20 years no matter what,” she said Friday.

“We cannot get off coal fast enough in this company, and gas right now in Alberta is extremely inexpensive…

“So our coal-to-gas strategy is completely predicated on our belief that it’s not smart to be in carbon-intensive fuels for the future.”

Elsewhere in Canada, the Stop the Shock campaign has advocated for reviving coal power, underscoring ongoing policy debates.

The company said it’s planning the coal-to-gas conversion and re-powering of some or all of the units at its Keephills and Sundance facilities to gas-fired generation sometime between 2020 and 2023.

Similarly, Capital Power CEO Brian Vaasjo said the Edmonton-based company is moving ahead with a project that will allow it to burn both coal and natural gas at its Genesee generating station, even as Ontario’s energy minister sought to explore a halt to natural gas generation elsewhere.

In June, the company announced it would spend an estimated $50 million between 2019 and 2021 to allow it to use gas at the facility.

“What we’re doing is going to be dual fuel, so we will be able to operate 100 per cent natural gas or 100 per cent coal and everything in between,” Vaasjo said in an interview.

“You can expect to see we will be burning coal in the winter when natural gas prices are high, and we will be burning natural gas in summer when gas prices are real low.”

The transition comes as the government’s decision to stick with the energy-only market has been welcomed by players in the industry, and as Alberta's electricity future increasingly leans on wind resources.

A study by electricity consultancy EDC Associates found the capacity market would result in consumers paying an extra $1.4 billion in direct costs in 2021-22, as it required more generation to come online earlier than expected.

These additional costs would have accumulated to $10 billion by 2030, said EDC chief executive Duane-Reid Carlson.

For Capital Power, the decision to stick with the current system makes the province more investable in the future. Vaasjo said there was great uncertainty about the transition to a capacity market, and the possibility of rules shifting further.

Officials with Enmax Corp. said the city-owned utility would not have invested in future generation under the proposed capacity market.

“There is no short-term need (today) for new generation, so we’re just looking at the market and saying, ‘OK, as it evolves, we will see what happens,’” said Enmax vice-president Tim Boston.

Sticking with the energy-only market doesn’t mean Alberta will keep the existing rules.

In a July 25 letter, Alberta Energy Minister Sonya Savage directed AESO chair Will Bridge to examine if changes to the existing market are needed and report back by July 2020.

AESO, which manages the power grid, has been asked to investigate whether the current price cap of $999 per megawatt-hour (MW-h) should be changed.

The price ceiling hasn’t been altered since the energy-only market was implemented by the Klein government about two decades ago.

While allowing prices to go higher would increase volatility, reflecting lessons from Europe’s power crisis about scarcity pricing, during periods of rising demand and limited supply, it would send a signal to generators when investment in new generation is required, said Kent Fellows, a research associate at the University of Calgary’s School of Public Policy.

“Keeping the price (cap) too low could end up costing us more in the long run,” he said.

In a 2016 report, AESO said the province examined raising the price cap to $5,000 per MW-h, but “determined that it was unlikely to be successful in attracting investment due to increased price volatility.”

However, the amount of future generation that will be required in Alberta has been scaled back by the province.

In the United States, the Electricity Reliability Council of Texas (ERCOT) allows wholesale power prices in the state to climb to a cap of $9,000 per megawatt hours as demand rises — as it did Tuesday in the midst of a heat wave, according to Bloomberg.

Jim Wachowich, legal counsel for the Consumers’ Coalition of Alberta, said while few players are exposed to spot electricity prices, he has yet to be convinced raising the cap would be good for Albertans.

“Someone has to show me the evidence, and I suspect that’s what the minister has asked the AESO to do,” he said.

Generators say they believe some tinkering is needed to the energy-only market to ensure new generation is built when it’s required.

“The No. 1 change that the government has to … think about is in pricing,” added Farrell.

“If you don’t have enough of a price signal in an energy-only market to attract new capital, you won’t get new capital — and you’ll run up against the wall.”

Related News

• Electricity Forum News

• Power Generation News

Texas EV Registration Fee adds a $200 annual charge under Senate Bill 505, offsetting lost gasoline tax revenue to the State Highway Fund, impacting electric vehicle owners at registration and renewals across Texas.

Key Points

A $200 yearly charge on electric vehicles to replace lost gasoline tax revenue and support Texas Highway Fund road work.

✅ $200 due at registration or renewal; $400 upfront on new EVs.

✅ Enacted by Senate Bill 505 to offset lost gasoline tax revenue.

✅ Advocates propose mileage-based fees; limited $2,500 rebates exist.

Plano resident Tony Federico bought his Tesla five years ago in part because he hated spending lots of money on gas, and Supercharger billing changes have also influenced charging expenses. But that financial calculus will change slightly on Sept. 1, when Texas will start charging electric vehicle drivers an additional fee of $200 each year.

“It just seems like it’s arbitrary, with no real logic behind it,” said Federico, 51, who works in information technology. “But I’m going to have to pay it.”

Earlier this year, state lawmakers passed Senate Bill 505, which requires electric vehicle owners to pay the fee when they register a vehicle or renew their registration, even as fights for control over charging continue among utilities, automakers and retailers. It’s being imposed because lawmakers said EV drivers weren’t paying their fair share into a fund that helps cover road construction and repairs across Texas.

The cost will be especially high for those who purchase a new electric vehicle and have to pay two years of registration, or $400, up front.

Texas agencies estimated in a 2020 report that the state lost an average of $200 per year in federal and state gasoline tax dollars when an electric vehicle replaced a gas-fueled one. The agencies called the fee “the most straightforward” remedy.

Gasoline taxes go to the State Highway Fund, which the Texas Department of Transportation calls its “primary funding source.” Electric vehicle drivers don’t pay those taxes, though, because they don’t use gasoline.

Still, EV drivers do use the roads. And while electric vehicles make up a tiny portion of cars in Texas for now, that fraction is expected to increase, raising concerns about state power grids in the years ahead.

Many environmental and consumer advocates agreed with lawmakers that EV drivers should pay into the highway fund but argued over how much, and debates over fairer vehicle taxes are surfacing abroad as well.

Some thought the state should set the fee lower to cover only the lost state tax dollars, rather than both the state and federal money, because federal officials may devise their own scheme. Others argued the state should charge nothing because EVs help reduce greenhouse gas emissions that drive climate change and can offer budget benefits for many owners.

“We urgently need to get more electric vehicles on the road,” said Luke Metzger, executive director of Environment Texas. “Any increased fee could create an additional barrier for Texans, and particularly more moderate- to low-income Texans, to make that transition.”

Tom “Smitty” Smith, the executive director of the Texas Electric Transportation Resources Alliance, advocated for a fee based on how many miles a person drove their electric car, which would better mirror how the gas taxes are assessed.

Texas has a limited incentive that could offset the cost: It offers rebates of up to $2,500 for up to 2,000 new hydrogen fuel cell, electric or hybrid vehicles every two years. Adrian Shelley, Public Citizen’s Texas office director, recommended that the state expand the rebates, noting that state-level EV benefits can be significant.

In the Houston area, dealer Steven Wolf isn’t worried about the fee deterring potential customers from buying the electric Ford F-150 Lightning and Mustang Mach-E vehicles he sells. Electric cars are already more expensive than comparable gasoline-fueled cars, and charging networks compete for drivers, he said.

Related News

• Electricity Forum News

• EV Infrastructure News

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.

Related News

• Electricity Forum News

• Renewable Energy News