Solar panels described as “eyesores”

Ontario electricity emissions forecast highlights rising grid CO2 as nuclear refurbishments and the Pickering closure drive more natural gas, limited renewables, and delayed Quebec hydro imports, pending advances in storage and transmission upgrades.

Key Points

A projection that Ontario's grid CO2 will rise as nuclear units refurbish or retire, increasing natural gas use.

✅ Nuclear refurbs and Pickering shutdown cut zero-carbon baseload

✅ Gas plants fill capacity gaps, boosting GHG emissions

✅ Quebec hydro imports face cost, transmission, and timing limits

Ontario's energy grid is among the cleanest in North America — but the province’s nuclear plans mean that some of our progress will be reversed over the next decade.

What was once Canada’s largest single source of greenhouse-gas emissions is now a solar-power plant. The Nanticoke Generating Station, a coal-fired power plant in Haldimand County, was decommissioned in stages from 2010 to 2013 — and even before the last remaining structures were demolished earlier this year, Ontario Power Generation had replaced its nearly 4,000 megawatts with a 44-megawatt solar project in partnership with the Six Nations of the Grand River Development Corporation and the Mississaugas of the Credit First Nation.

But neither wind nor solar has done much to replace coal in Ontario’s hydro sector, a sign of how slowly Ontario is embracing clean power in practice across the province. At Nanticoke, the solar panels make up less than 2 per cent of the capacity that once flowed out to southern Ontario over high-voltage transmission lines. In cleaning up its electricity system, the province relied primarily on nuclear power — but the need to extend the nuclear system’s lifespan will end up making our electricity dirtier again.

“We’ve made some pretty great strides since 2005 with the fuel mix,” says Terry Young, vice-president of corporate communications at the Independent Electricity System Operator, the provincial agency whose job it is to balance supply and demand in Ontario’s electricity sector. “There have been big changes since 2005, but, yes, we will see an increase because of the closure of Pickering and the refurbs coming.”

“The refurbs” is industry-speak for the major rebuilds of both the Darlington and Bruce nuclear-power stations. The two are both in the early stages of major overhauls intended to extend their operating lives into the 2060s: in the coming years, they’ll be taken offline and rebuilt. (The Pickering nuclear plant will not be refurbished and will shut down in 2024.)

The catch is that, as the province loses its nuclear capacity in increments, Ontario will be short of electricity in the coming years and the IESO will need to find capacity elsewhere to make sure the lights stay on. And that could mean burning a lot more natural gas — and creating more greenhouse-gas emissions.

According to the IESO’s planning assumptions, electricity will be responsible for 11 megatonnes of greenhouse-gas emissions annually by 2035 (last year, it was three megatonnes). That’s the “reference case” scenario: if conservation and efficiency policies shave off some electricity demand, we could get it down to something like nine megatonnes. But if demand is higher than expected, it could be as high as 13 megatonnes — more than quadruple Ontario’s 2018 emissions.

Even in the worst-case scenario, the province’s emissions from electricity would still be less than half of what they were in 2005, before the province began phasing out its coal generation. But it’s still a reversal of a trend that both Liberals and Progressive Conservatives have boasted about — the Liberals to justify their energy policies, the PCs to justify their hostility to a federal carbon tax.

Young emphasized that technology can change and that the IESO’s planning assumptions are just that: projections based on the information available today. A revolution in electricity storage could make it possible to store the province’s cleaner power sources overnight for use during the day, but that’s still only in the realm of speculation — and the natural-gas infrastructure exists in the real world, today.

Ontario Power Generation — the Crown corporation that operates many of the province’s power plants, including Pickering and Darlington — recently bought four gas plants, two of them outright (two it already owned in part). All were nearly complete or already operational, so the purchase itself won’t change the province’s emissions prospects. Rather, OPG is simply looking to maintain its share of the electricity market after the Pickering shutdown.

“It will allow us to maintain our scale, with the upcoming end of Pickering’s commercial operations, so that we can continue our role as the driver of Ontario’s lower carbon future,” Neal Kelly, OPG’s director of media, issues, and management, told TVO.org via email. “Further, there is a growing need for flexible gas fired generation to support intermittent wind and solar generation.”

The shift to more gas-fired generation has been coming for a while, and critics say that Ontario has missed an opportunity to replace the lost Pickering capacity with something cleaner. MPP Mike Schreiner, leader of the Green party, has argued for years that Ontario should have pursued an agreement with Quebec to import clean hydroelectricity.

“To me, it’s a cost-effective solution, and it’s a zero-emissions solution,” Schreiner says. “Regardless of your position on sources of electricity, I think everyone could agree that waterpower from Quebec is going to be less expensive.”

Quebec is eager to sell Ontario its surplus hydro power, but not everyone agrees that importing power would be cheaper. A study published by the Ontario Chamber of Commerce (and commissioned by Ontario Power Generation) calls the claim a “myth” and states that upgrading electric-transmission wires between Ontario and Quebec would cost $1.2 billion and take 10 years, while some estimates suggest fully greening Ontario's grid would cost far more overall.

With Quebec imports seemingly a non-starter and major changes to Ontario’s nuclear fleet already underway, there’s only one path left for this province’s greenhouse-gas emissions: upwards.

Related News

• Electricity Forum News

• Power Generation News

Electricity Market Competition drives lower wholesale prices, stable retail rates, better grid reliability, and faster emissions cuts as deregulation and renewables adoption pressure utilities, improve efficiency, and enhance consumer choice in power markets.

Key Points

Electricity market competition opens supply to rivals, lowering prices, improving reliability, and reducing emissions.

✅ Wholesale prices fell faster in competitive markets

✅ Retail rates rose less than in monopoly states

✅ Fewer outages, shorter durations, improved reliability

By Bernard L. Weinstein

Electricity used to be boring.  Public utilities that provided power to homes and businesses were regulated monopolies and, by law, guaranteed a fixed rate-of-return on their generation, transmission, and distribution assets. Prices per kilowatt-hour were set by utility commissions after lengthy testimony from power companies, wanting higher rates, and consumer groups, wanting lower rates.

About 25 years ago, the electricity landscape started to change as economists and others argued that competition could lead to lower prices and stronger grid reliability. Opponents of competition argued that consumers weren’t knowledgeable enough about power markets to make intelligent choices in a competitive pricing environment. Nonetheless, today 20 states have total or partial competition for electricity, allowing independent power generators to compete in wholesale markets and retail electric providers (REPs) to compete for end-use customers, a dynamic echoed by the Alberta electricity market across North America. (Transmission, in all states, remains a regulated natural monopoly).

A recent study by the non-partisan Pacific Research Institute (PRI) provides compelling evidence that competition in power markets has been a boon for consumers. Using data from the U.S. Energy Information Administration (EIA), PRI’s researchers found that wholesale electricity prices in competitive markets have been generally declining or flat, prompting discussions of free electricity business models, over the last five years. For example, compared to 2015, wholesale power prices in New England have dropped more than 44 percent, those in most Mid-Atlantic States have fallen nearly 42 percent, and in New York City they’ve declined by nearly 45 percent. Wholesale power costs have also declined in monopoly states, but at a considerably slower rate.

As for end-users, states that have competitive retail electricity markets have seen smaller price increases, as consumers can shop for electricity in Texas more cheaply than in monopoly states. Again, using EIA data, PRI found that in 14 competitive jurisdictions, retail prices essentially remained flat between 2008 and 2020. By contrast, retail prices jumped an average of 21 percent in monopoly states.  The ten states with the largest retail price increases were all monopoly-based frameworks. A 2017 report from the Retail Energy Supply Association found customers in states that still have monopoly utilities saw their average energy prices increase nearly 19 percent from 2008 to 2017 while prices fell 7 percent in competitive markets over the same period.

The PRI study also observed that competition has improved grid reliability, the recent power disruptions in California and Texas, alongside disruptions in coal and nuclear sectors across the U.S., notwithstanding. Looking at two common measures of grid resiliency, PRI’s analysis found that power interruptions were 10.4 percent lower in competitive states while the duration of outages was 6.5 percent lower.

Citing data from the EIA between 2008 and 2018, PRI reports that greenhouse gas emissions in competitive states declined on average 12.1 percent compared to 7.3 percent in monopoly states. This result is not surprising, and debates over whether Israeli power supply competition can bring cheaper electricity mirror these dynamics.  In a competitive wholesale market, independent power producers have an incentive to seek out lower-cost options, including subsidized renewables like wind and solar. By contrast, generators in monopoly markets have no such incentive as they can pass on higher costs to end-users. Perhaps the most telling case is in the monopoly state of Georgia where the cost to build nuclear Plant Vogtle has doubled from its original estimate of $14 billion 12 years ago. Overruns are estimated to cost Georgia ratepayers an average of $854, and there is no definite date for this facility to come on line. This type of mismanagement doesn’t occur in competitive markets.

Unfortunately, some critics are attempting to halt the momentum for electricity competition and have pointed to last winter’s “deep freeze” in Texas that left several million customers without power for up to a week. But this example is misplaced. Power outages in February were the result of unprecedented and severe weather conditions affecting electricity generation and fuel supply, and numerous proposals to improve Texas grid reliability have focused on weatherization and fuel resilience; the state simply did not have enough access to natural gas and wind generation to meet demand. Competitive power markets were not a factor.

The benefits of wholesale and retail competition in power markets are incontrovertible. Evidence shows that households and businesses in competitive states are paying less for electricity while grid reliability has improved. The facts also suggest that wholesale and retail competition can lead to faster reductions in greenhouse gas emissions. In short, competition in power markets is good for consumers and good for the environment.

Bernard L. Weinstein is emeritus professor of applied economics at the University of North Texas, former associate director of the Maguire Energy Institute at Southern Methodist University, and a fellow of Goodenough College, London. He wrote this for InsideSources.com.

Related News

• Electricity Forum News

• Energy Policy News

DOE Environmental Management Funding Boost seeks $7.25B to accelerate nuclear cleanup, upgrade Savannah River Site infrastructure, create jobs, and support small businesses, echoing ARRA 2009 results and expediting DOE EM waste remediation nationwide.

Key Points

A proposed $7.25B stimulus for DOE's EM to accelerate nuclear cleanup, modernize infrastructure, and create jobs.

✅ $7.25B one-time stimulus for DOE EM cleanup and infrastructure.

✅ Targets Savannah River Site; supports jobs and small businesses.

✅ Builds on ARRA 2009; accelerates nuclear waste remediation.

A bloc of local governments and nuclear industry, nuclear innovation efforts, labor and community groups are pressing Congress to provide a one-time multibillion-dollar boost to the U.S. Department of Energy Office of Environmental Management, the remediation-focused Savannah River Site landlord.

The organizations and officials -- including Citizens For Nuclear Technology Awareness Executive Director Jim Marra and Savannah River Site Community Reuse Organization President and CEO Rick McLeod -- sent a letter Friday to U.S. House and Senate leadership "strongly" supporting a $7.25 billion funding injection, even as ACORE challenges coal and nuclear subsidies in separate regulatory proceedings, arguing it "will help reignite the national economy," help revive small businesses and create thousands of new jobs despite the novel coronavirus crisis.

More than 30 million Americans have filed unemployment claims in the past two months, with additional clean energy job losses reported, too. Hundreds of thousands of claims have been filed in South Carolina since mid-March, compounding issues like unpaid utility bills in neighboring states.

The requested money could, too, speed Environmental Management's nuclear waste cleanup missions and be used to fix ailing infrastructure and strengthen energy security for rural communities nationwide -- some of which dates back to the Cold War -- at sites across the country. That's a "rare" opportunity, reads the letter, which prominently features the Energy Communities Alliance logo and its chairman's signature.

Similar funding programs, like what was done with the 2009 American Recovery and Reinvestment Act and recent clean energy funding initiatives, have been successful.

At the time, amid a staggering economic downturn nationwide, Environmental Management contractors "hired over 20,000 new workers," putting them "to work to reduce the overall cleanup complex footprint by 688 square miles while strengthening local economies," the Friday letter reads.

The Energy Department's cleanup office estimates the $6 billion investment years ago reduced its environmental liability by $13 billion, according to a 2012 report.

Such a leap forward, the coalition believes, is repeatable, a view reflected in current plans to revitalize coal communities with clean energy projects across the country.

"We are confident that DOE can successfully manage increased funding and leverage it for future economic development as it has in the past," the letter states. It continues: "We take pride in working together to support jobs and development of infrastructure and work that make our country stronger and assists us to recover from the impacts of COVID-19."

As of Monday afternoon, 8,942 cases of COVID-19, the disease caused by the novel coronavirus, have been logged in South Carolina. Aiken County is home to 155 of those cases.

Related News

• Electricity Forum News

• Energy Policy News

Texas Deep Freeze Energy Crisis strains grids as polar vortex triggers rolling blackouts, record natural gas and electricity prices, refinery shutdowns, WTI gains, and scarcity pricing across Texas, Oklahoma, SPP, and Mexico.

Key Points

A polar vortex slamming Texas energy: outages, record power prices, gas spikes, and reduced oil output.

✅ Record gas trades near $500/mmBtu; power hits $6,000/MWh

✅ WTI tops $60 as Texas shuts in ~1 million bpd

✅ Rolling blackouts across SPP; ERCOT scarcity pricing

A deep freeze is roiling electricity markets in more than a dozen U.S. states, leading to record-setting prices for electricity and natural gas, knocking oil production off line and shutting down some of North America’s largest refineries.

“It’s freakishly cold,” said Eric Fell, a senior natural gas analyst with Wood Mackenzie in Houston, where record cold temperatures and snow have blanketed the city, caused rolling power outages, shut down refineries and sent both natural gas and electricity prices soaring.

'It’s freakishly cold': Deep freeze slams North American energy sector

The polar vortex has led to freezing temperatures in every county in Texas, the largest energy-producing state in the U.S., and caused massive disruptions across the North American energy complex, triggering Texas power outages as far south as Mexico.

As the plunge in temperatures forced oil companies to shut in an estimated one million barrels of oil production in Texas on Monday, the West Texas Intermediate benchmark price rose above the US$60 per barrel threshold for the first time in a year to settle up 1 per cent, or US65 cents, at US$60.12 per barrel.

President Joe Biden declared an emergency on Monday, unlocking federal assistance to Texas.

People carry groceries from a local gas station on Monday in Austin, Texas. Winter storm Uri has brought historic cold weather to Texas, causing traffic delays and power outages. 

Frozen wind farms are just a small piece of Texas’s power grid woes right now.

Fell said regional natural gas and electricity prices in Oklahoma and Texas broke U.S. records over the weekend.

On Friday, Oklahoma gas transmission prices averaged US$350 per million British thermal units and Fell said one trade went as high as US$600 per mmBtu. In parts of the Texas panhandle and elsewhere, prices jumped to US$200, “all of which individually would have been new records,” Fell said, noting the previous record was US$160.

On Monday, natural gas for physical delivery in the U.S. was trading for as much as US$500 per mmBtu as demand for the heating and power plant fuel soared.  Spot gas has been trading for hundreds of dollars across the central U.S. since Thursday with a surge in heating demand triggering widespread blackouts and sending electricity prices soaring. The fuel normally trades in the region for less than US$3 per mmBtu.

Similarly, electricity prices in Texas surged to US$6,000 per megawatt hour on Monday, as U.S. power companies grapple with supply-chain constraints, which Fell said is “100 times the normal price.”

“You’re seeing scarcity pricing in power and gas. The only thing that’s different this time is it’s staying there – it’s not just an hour or two hours, it’s the whole day,” he said.

The blast of Arctic cold, which has blanketed Canada and much of the U.S., has created a massive draw on natural gas supplies, used both for home heating and industrial uses like electricity generation.

Little Rock, Ark.-based Southwest Power Pool, which coordinates electricity distribution for parts of 14 states including Oklahoma Kansas, Nebraska and even as far north as North Dakota, announced rolling blackouts across its network on Monday as a result of the power outages.

“In our history as a grid operator, this is an unprecedented event and marks the first time SPP has ever had to call for controlled interruptions of service” SPP’s executive vice-president and chief operating officer Lanny Nickell said in a release, adding the move was “a last resort” to “prevent circumstances from getting worse.”

The frigid conditions have led to a surge in natural gas prices across the continent, including in Alberta where the AECO benchmark price jumped to a seven-year high of $6.36 per thousand cubic feet last week, a price not seen since 2014.

Energy systems in Texas and Oklahoma, which are major energy exporters to other U.S. states, are built to withstand severe heat – not extreme cold. The result is a disruption to the gas supply at exactly the time the U.S. energy system is demanding those molecules.

“Given how far south it’s gone into Texas, this is where you have a lot of gas production that isn’t properly winterized,” said Jeremy McCrea, an analyst with Raymond James covering the natural gas industry.

Related News

• Electricity Forum News

• Energy Policy News

Electricity System Climate Resilience underpins grid reliability amid heatwaves and drought, integrating solar, wind, hydropower, nuclear, storage, and demand response with efficient transmission, flexibility, and planning to secure power for homes, industry, and services.

Key Points

Power systems capacity to endure extreme weather and integrate clean energy, maintaining reliability and flexibility.

✅ Grid hardening, transmission upgrades, and digital forecasting.

✅ Flexible low-carbon supply: hydropower, nuclear, storage.

✅ Demand response, efficient cooling, and regional integration.

Summer is just half done in the northern hemisphere and yet we are already seeing electricity systems around the world struggling to cope with the severe strain of heatwaves and low rainfall.

These challenges highlight the urgent need for strong and well-planned policies and investments to improve the security of our electricity systems, which supply power to homes, offices, factories, hospitals, schools and other fundamental parts of our economies and societies. This means making our electricity systems more resilient to the effects of global warming – and more efficient and flexible as they incorporate rising levels of solar and wind power, as solar is now the cheapest electricity in history according to the IEA, which will be critical for reaching net-zero emissions in time to prevent even worse impacts from climate change.

A range of different countries, including the US, Canada and Iraq, have been hard hit by extreme weather recently in the form of unusually high temperatures. In North America, the heat soared to record levels in the Pacific Northwest. An electricity watchdog says that five US regions face elevated risks to the security of their electricity supplies this summer, underscoring US grid climate risks that could worsen, and that California’s risk level is even higher.

Heatwaves put pressure on electricity systems in multiple ways. They increase demand as people turn up air conditioning, driving higher US electricity bills for many households, and as some appliances work harder to maintain cool temperatures. At the same time, higher temperatures can also squeeze electricity supplies by reducing the efficiency and capacity of traditional thermal power plants, such as coal, natural gas and nuclear. Extreme heat can reduce the availability of water for cooling plants or transporting fuel, forcing operators to reduce their output. In some cases, it can result in power plants having to shut down, increasing the risk of outages. If the heat wave is spread over a wide geographic area, it also reduces the scope for one region to draw on spare capacity from its neighbours, since they have to devote their available resources to meeting local demand.

A recent heatwave in Texas forced the grid operator to call for customers to raise their thermostats’ temperatures to conserve energy. Power generating companies suffered outages at much higher rates than expected, providing an unwelcome reminder of February’s brutal cold snap when outages – primarily from natural gas power plants – left up to 5 million customers across the US without power over a period of four days.

At the same time, lower than average rainfall and prolonged dry weather conditions are raising concerns about hydropower’s electricity output in various parts of the world, including Brazil, China, India and North America. The risks that climate change brings in the form of droughts adds to the challenges faced by hydropower, the world’s largest source of clean electricity, highlighting the importance of developing hydropower resources sustainably and ensuring projects are climate resilient.

The recent spate of heatwaves and unusually long dry spells are fresh warnings of what lies ahead as our climate continues to heat up: an increase in the scale and frequency of extreme weather events, which will cause greater impacts and strains on our energy infrastructure.

Heatwaves will increase the challenge of meeting electricity demand while also decarbonizing the electricity supply. Today, the amount of energy used for cooling spaces – such as homes, shops, offices and factories – is responsible for around 1 billion tonnes of global CO2 emissions. In particular, energy for cooling can have a major impact on peak periods of electricity demand, intensifying the stress on the system. Since the energy demand used for air conditioners worldwide could triple by 2050, these strains are set to grow unless governments introduce stronger policy measures to improve the energy efficiency of air conditioning units.

Electricity security is crucial for smooth energy transitions
Many countries around the world have announced ambitious targets for reaching net-zero emissions by the middle of this century and are seeking to step up their clean energy transitions. The IEA’s recent Global Roadmap to Net Zero by 2050 makes it clear that achieving this formidable goal will require much more electricity, much cleaner electricity and for that electricity to be used in far more parts of our economies than it is today. This means electricity reaching much deeper into sectors such as transport (e.g. EVs), buildings (e.g. heat-pumps) and industry (e.g. electric-arc steel furnaces), and in countries like New Zealand's electrification plans it is accelerating broader efforts. As clean electricity’s role in the economy expands and that of fossil fuels declines, secure supplies of electricity become ever-more important. This is why the climate resilience of the electricity sector must be a top priority in governments’ policy agendas.

Changing climate patterns and more frequent extreme weather events can hit all types of power generation sources. Hydropower resources typically suffer in hot and dry conditions, but so do nuclear and fossil fuel power plants. These sources currently help ensure electricity systems have the flexibility and capacity to integrate rising shares of solar and wind power, whose output can vary depending on the weather and the time of day or year.

As governments and utilities pursue the decarbonization of electricity systems, mainly through growing levels of solar and wind, and carbon-free electricity options, they need to ensure they have sufficiently robust and diverse sources of flexibility to ensure secure supplies, including in the event of extreme weather events. This means that the possible decommissioning of existing power generation assets requires careful assessments that take into account the importance of climate resilience.

Ensuring electricity security requires long-term planning and stronger policy action and investment
The IEA is committed to helping governments make well-informed decisions as they seek to build a clean and secure energy future. With this in mind, here are seven areas for action for ensuring electricity systems are as resilient as possible to climate risks:

1. Invest in electricity grids to make them more resilient to extreme weather. Spending today is far below the levels needed to double the investment for cleaner, more electrified energy systems, particularly in emerging and developing economies. Economic recovery plans from the COVID-19 crisis offer clear opportunities for economies that have the resources to invest in enhancing grid infrastructure, but much greater international efforts are required to mobilize and channel the necessary spending in emerging and developing economies.

2. Improve the efficiency of cooling equipment. Cost-effective technology already exists in most markets to double or triple the efficiency of cooling equipment. Investing in higher efficiency could halve future energy demand and reduce investment and operating costs by $3 trillion between now and 2050. In advance of COP26, the Super-Efficient Equipment and Appliance Deployment (SEAD) initiative is encouraging countries to sign up to double the energy efficiency of equipment sold in their countries by 2030.

3. Enable the growth of flexible low-carbon power sources to support more solar and wind. These electricity generation sources include hydropower and nuclear, for countries who see a role for one or both of them in their energy transitions. Guaranteeing hydropower resilience in a warming climate will require sophisticated methods and tools – such as the ones implemented in Brazil – to calculate the necessary level of reserves and optimize management of reservoirs and hydropower output even in exceptional conditions. Batteries and other forms of storage, combined with solar or wind, can also provide important amounts of flexibility by storing power and releasing it when needed.

4. Increase other sources of electricity system flexibility. Demand-response and digital technologies can play an important role. The IEA estimates that only a small fraction of the huge potential for demand response in the buildings sector is actually tapped at the moment. New policies, which associate digitalization and financial behavioural incentives, could unlock more flexibility. Regional integration of electricity systems across national borders can also increase access to flexible resources.

5. Expedite the development and deployment of new technologies for managing extreme weather threats. The capabilities of electricity utilities in forecasting and situation awareness should be enhanced with the support of the latest information and communication technologies.

6. Make climate resilience a central part of policy-making and system planning. The interconnected nature of recent extreme weather events reminds us that we need to account for many contingencies when planning resilient power systems. Climate resilience should be integral to policy-making by governments and power system planning by utilities and relevant industries, and debates over Canadian climate policy underscore how grid implications must be considered. According to the recent IEA report on climate resilience, only nine out of 38 IEA member and association countries include concrete actions on climate adaptation and resilience for every segment of electricity systems.

7. Strengthen international cooperation on electricity security. Electricity underpins vital services and basic needs, such as health systems, water supplies and other energy industries. Maintaining a secure electricity supply is thus of critical importance. The costs of doing nothing in the face of growing climate threats are becoming abundantly clear. The IEA is working with all countries in the IEA family, as well as others around the world, by providing unrivalled data, analysis and policy advice on electricity security issues. It is also bringing governments together at various levels to share experiences and best practices, and identify how to hasten the shift to cleaner and more resilient energy systems.

Related News

• Electricity Forum News

• Climate Change 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