Coal plant backers still fired up about prospects

Alberta Hydropower Potential highlights renewable energy, dams, reservoirs, grid flexibility, contrasting wind and solar growth with limited investment, regulatory hurdles, river basin resources, and decarbonization pathways across Athabasca, Peace, and Slave River systems.

Key Points

It is the technical capacity for new hydro in Alberta's river basins to support a more reliable, lower carbon grid.

✅ 42,000 GWh per year developable hydro identified in studies.

✅ Major potential in Athabasca, Peace, and Slave River basins.

✅ Barriers include high capital costs, market design, water rights.

When you think about renewable energy sources on the Prairies, your mind may go to the wind farms in southern Alberta, or even the Travers Solar Project, southeast of Calgary.

Most of the conversation around renewable energy in the province is dominated by advancements in solar and wind power, amid Alberta's renewable energy surge that continues to attract attention. 

But what about Canada's main source of electricity — hydro power?

More than half of Canada's electricity is generated from hydro sources, with 632.2 terawatt-hours produced as of 2019. That makes it the fourth largest installed capacity of hydropower in the world. 

But in Alberta, it's a different story. 

Currently, hydro power contributes between three and five per cent of Alberta's energy mix, while fossil fuels make up about 89 per cent.

According to Canada's Energy Future report from the Canada Energy Regulator, by 2050 it will make up two per cent of the province's electricity generation shares.

So why is it that a province so rich in mountains and rivers has so little hydro power?

Hydro's history in Alberta
Hydro power didn't always make up such a small sliver of Alberta's electricity generation. Hydro installations began in the early 20th century as the province's population exploded. 

Grant Berg looks after engineering for hydro for TransAlta, Alberta's largest producer of hydro power with 17 facilities across the province.

"Our first plant was Horseshoe, which started in 1911 that we formed as Calgary Power," he said. 

"It was really in response to the City of Calgary growing and having some power needs."

Berg said in 1913, TransAlta's second installation, the Kananaskis Plant, started as Calgary continued to grow.

A historical photo of a hydro-electric dam in Kananaskis Alta. taken in 1914.
Hydro power plant in Kananaskis as seen in 1914. (Glenbow Archives)
Some bigger installations were built in the 1920s, including Ghost reservoir, but by mid-century population growth increased.

"Quite a large build out really, I think in response to the growth in Alberta following the war. So through the 1950s really quite a large build out of hydro from there."

By the 1950s, around half of the province's installed capacity was hydro power.

"Definitely Calgary power was all hydro until the 1950s," said Berg. 

Hydro potential in the province 
Despite the current low numbers in hydroelectricity, Alberta does have potential. 

According to a 2010 study, there is approximately 42,000 gigawatt-hours per year of remaining developable hydroelectric energy potential at identified sites. 

An average home in Alberta uses around 7,200 kilowatt-hours of electricity per year, meaning that the hydro potential could power 5.8 million homes each year. 

"This volume of energy could be sufficient to serve a significant amount of Alberta's load and therefore play a meaningful role in the decarbonization of the province's electric system," the Alberta Electric System Operator said in its 2022 Pathways to Net-Zero Emissions report.

Much of that potential lies in northern Alberta, in the Athabasca, Peace and Slave River basins.

The AESO report says that despite the large resource potential, Alberta's energy-only market framework has attracted limited investment in hydroelectric generation. 

Hydro power was once a big deal in Alberta, but investment in the industry has been in decline since the 1950s. Climate change reporter Christy Climenhaga explains why.
So why does Alberta leave out such a large resource potential on the path to net zero?

The government of Alberta responded to that question in a statement. 

"Hydro facilities, particularly large scale ones involving dams, are associated with high costs and logistical demands," said the Ministry of Affordability and Utilities. 

"Downstream water rights for other uses, such as irrigation, further complicate the development of hydro projects."

The ministry went on to say that wind and solar projects have increased far more rapidly because they can be developed at relatively lower cost and shorter timelines, and with fewer logistical demands.

"Sources from wind power and solar are increasingly more competitive," said Jean-Denis Charlebois, chief economist with the Canadian Energy Regulator. 

Hydro on the path to net zero
Hydro power is incredibly important to Canada's grid, and will remain so, despite growth in wind and solar power across the province.

Charlebois said that across Canada, the energy make-up will depend on the province. 

"Canadian provinces will generate electricity in very different ways from coast to coast. The major drivers are essentially geography," he said. 

Charlebois says that in British Columbia, Manitoba, Quebec and Newfoundland and Labrador, hydropower generation will continue to make up the majority of the grid.

"In Alberta and Saskatchewan, we see a fair bit of potential for wind and solar expansion in the region, which is not necessarily the case on Canada's coastlines," he said.

And although hydro is renewable, it does bring its adverse effects to the environment — land use changes, changes in flow patterns, fish populations and ecosystems, which will have to be continually monitored. 

"You want to be able to manage downstream effects; make sure that you're doing all the proper things for the environment," said Ryan Braden, director of mining and hydro at TransAlta.

Braden said hydro power still has a part to play in Alberta, even with its smaller contributions to the future grid. 

"It's one of those things that, you know, the wind doesn't blow or the sun doesn't shine, this is here. The way we manage it, we can really support that supply and demand," he said.

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Japan Electricity Crunch exposes vulnerabilities in a liberalised power market as LNG shortages, JEPX price spikes, snow-hit solar, and weak hedging strain energy security and retail providers amid cold snap demand and limited reserve capacity.

Key Points

A winter demand shock and LNG shortfalls sent JEPX to records, exposing gaps in hedging, data, and energy security.

✅ JEPX wholesale prices spiked to an all-time high

✅ LNG inventories and procurement proved insufficient

✅ Snow disabled solar; new entrants lacked hedging

Japan's worst electricity crunch since the aftermath of the Fukushima crisis has exposed vulnerabilities in the country's recently liberalised power market, although some of the problems appear self-inflicted.

Power prices in Japan hit record highs last month, mirroring UK peak power prices during tight conditions, as a cold snap across northeast Asia prompted a scramble for supplies of liquefied natural gas (LNG), a major fuel for the country's power plants. Power companies urged customers to ration electricity to prevent blackouts, although no outages occurred.

The crisis highlighted how many providers were unprepared for such high demand. Experts say LNG stocks were not topped up ahead of winter and snow disabled solar power farms, while China's power woes strained solar supply chains.

The hundreds of small power companies that sprang up after the market was opened in 2016 have struggled the most, saying the government does not disclose the market data they need to operate. The companies do not have their own generators, instead buying electricity on the wholesale market.

Prices on the Japan Electric Power Exchange (JEPX) hit a record high of 251 yen ($2.39) per kilowatt hour in January, equating to $2,390 per megawatt hour of electricity, above record European price surges seen recently and the highest on record anywhere in the world. One megawatt hour is roughly what an average home in the U.S. would consume over 35 days.

But the vast majority of the new, smaller companies are locked into low, fixed rates they set to lure customers from bigger players, crushing them financially during a price spike like the one in January.

More than 50 small power providers wrote on Jan. 18 to Japan's industry minister, Hiroshi Kajiyama, who oversees the power sector, asking for more accessible data on supply and demand, reserve capacity and fuel inventories.

"By organising and disclosing this information, retail electricity providers will be able to bid at more appropriate prices," said the companies, led by Looop Co.

They also called on Kajiyama to require transmission and distribution companies to pass on some of the unexpected profits from price spikes to smaller operators.

The industry ministry said it had started releasing more timely market data, and is reviewing the cause of the crunch and considering changes, echoing calls by Fatih Birol to keep electricity options open amid uncertainty.

Japan reworked its power markets after the Fukushima nuclear disaster in 2011, liberalizing the sector in 2016 while pushing for more renewables.

But Japan is still heavily reliant on LNG and coal, and only four of 33 nuclear reactors are operating. The power crisis has led to growing calls to restart more reactors.

Kazuno Power, a small retail provider controlled by a municipality of the same name in northern Japan, where abundant renewable energy is locally produced, buys electricity from hydropower stations and JEPX.

During the crunch, the company had to pay nearly 10 times the usual price, Kazuno Power president Takao Takeda said in an interview. Like most other new providers, it could not pass on the costs, lost money, and folded. The local utility has taken over its customers.

"There is a contradiction in the current system," Takeda said. "We are encouraged to locally produce power for local consumption as well as use more renewable energy, but prices for these power supplies are linked to wholesale prices, which depend on the overall power supply."

The big utilities, which receive most of their LNG on long-term contracts, blamed the power shortfall on a tight spot market and glitches at generation units.

"We were not able to buy as much supply as we wanted from the spot market because of higher demand from South Korea and China, where power cuts have tightened supply," Kazuhiro Ikebe, the head of the country's electricity federation, said recently.

Ikebe is also president of Kyushu Electric Power, which supplies the southern island of Kyushu.

Utilities took extreme measures - from burning polluting fuel oil in coal plants to scavenging the dregs from empty LNG tankers - to keep the grid from breaking down.

"There is too much dependence on JEPX for procurement," said Bob Takai, the local head of European Energy Exchange, where electricity pricing reforms are being discussed, and which started offering Japan power futures last year. He added that new entrants were not hedging against sharp price moves.

Three people, who requested anonymity because of the sensitivity of the matter, were more blunt. One called the utilities arrogant in assuming they could find LNG cargoes in a pinch. Prices were already rising as China snapped up supplies, the sources noted.

"You had volatility caused by people saying 'Oh, well, demand is going to be weak because of coronavirus impacts' and then saying 'we can rely more on solar than in the past,' but solar got snowed out," said a senior executive from one generator. "We have a problem of who is charge of energy security in Japan."

Inventories of LNG, generally about two weeks worth of supplies, were also not topped up enough to prepare for winter, a market analyst said.

The fallout from the crunch has become more apparent in recent days, with new power companies like Rakuten Inc suspending new sales and Tokyo Gas, along with traditional electricity utilities, issuing profit downgrades or withdrawing their forecasts.

Although prices have fallen sharply as temperatures warmed up slightly and more generation units have come back online, the power generator executive said, "we are not out of the woods yet."
 

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European Energy Market Crisis drives record natural gas and electricity prices across the EU, as LNG supply constraints, Russian pipeline dependence, marginal pricing, and renewables integration expose volatility in liberalised power markets.

Key Points

A 2021 surge in European gas and electricity prices from supply strains, demand rebounds, and marginal pricing exposure.

✅ Record TTF gas and day-ahead power prices across Europe

✅ LNG constraints and Russian pipeline dependence tightened supply

✅ Debate over marginal pricing vs regulated models intensifies

By Ronan Bolton

The year 2021 was a turbulent one for energy markets across Europe, as Europe's energy nightmare deepened across the region. Skyrocketing natural gas prices have created a sense of crisis and will lead to cost-of-living problems for many households, as wholesale costs feed through into retail prices for gas and electricity over the coming months.

This has created immediate challenges for governments, but it should also encourage us to rethink the fundamental design of our energy markets as we seek to transition to net zero, with many viewing it as a wake-up call to ditch fossil fuels across the bloc.

This energy crisis was driven by a combination of factors: the relaxation of Covid-19 lockdowns across Europe created a surge in demand, while cold weather early in the year diminished storage levels and contributed to increasing demand from Asian economies. A number of technical issues and supply-side constraints also combined to limit imports of liquefied natural gas (LNG) into the continent.

Europe’s reliance on pipeline imports from Russia has once again been called into question, as Gazprom has refused to ride to the rescue, only fulfilling its pre-existing contracts. The combination of these, and other, factors resulted in record prices – the European benchmark price (the Dutch TTF Gas Futures Contract) reached almost €180/MWh on 21 December, with average day-ahead electricity prices exceeding €300/MWh across much of the continent in the following days.

Countries which rely heavily on natural gas as a source of electricity generation have been particularly exposed, with governments quickly put under pressure to intervene in the market.

In Spain the government and large energy companies have clashed over a proposed windfall tax on power producers. In Ireland, where wind and gas meet much of the country’s surging electricity demand, the government is proposing a €100 rebate for all domestic energy consumers in early 2022; while the UK government is currently negotiating a sector-wide bailout of the energy supply sector and considering ending the gas-electricity price link to curb bills.

This follows the collapse of a number of suppliers who had based their business models on attracting customers with low prices by buying cheap on the spot market. The rising wholesale prices, combined with the retail price cap previously introduced by the Theresa May government, led to their collapse.

While individual governments have little control over prices in an increasingly globalised and interconnected natural gas market, they can exert influence over electricity prices as these markets remain largely national and strongly influenced by domestic policy and regulation. Arising from this, the intersection of gas and power markets has become a key site of contestation and comment about the role of government in mitigating the impacts on consumers of rising fuel bills, even as several EU states oppose major reforms amid the price spike.

Given that renewables are constituting an ever-greater share of production capacity, many are now questioning why gas prices play such a determining role in electricity markets.

As I outline in my forthcoming book, Making Energy Markets, a particular feature of the ‘European model’ of liberalised electricity trade since the 1990s has been a reliance on spot markets to improve the efficiency of electricity systems. The idea was that high marginal prices – often set by expensive-to-run gas peaking plants – would signal when capacity limits are reached, providing clear incentives to consumers to reduce or delay demand at these peak periods.

This, in theory, would lead to an overall more efficient system, and in the long run, if average prices exceeded the costs of entering the market, new investments would be made, thus pushing the more expensive and inefficient plants off the system.

The free-market model became established during a more stable era when domestically-sourced coal, along with gas purchased on long-term contracts from European sources (the North Sea and the Netherlands), constituted a much greater proportion of electricity generation.

While prices fluctuated, they were within a somewhat predictable range, and provided a stable benchmark for the long-term contracts underpinning investment decisions. This is no longer the case as energy markets become increasingly volatile and disrupted during the energy transition.

The idea that free price formation in a competitive market, with governments standing back, would benefit electricity consumers and lead to more efficient systems was rooted in sound economic theory, and is the basis on which other major commodity markets, such as metals and agricultural crops, have been organised for decades.

The free-market model applied to electricity had clear limitations, however, as the majority of domestic consumers have not been exposed directly to real-time price signals. While this is changing with the roll-out of smart meters in many countries, the extent to which the average consumer will be willing or able to reduce demand in a predicable way during peak periods remains uncertain.

Also, experience shows that governments often come under pressure to intervene in markets if prices rise sharply during periods of scarcity, thus undermining a basic tenet of the market model, with EU gas price cap strategies floated as one option.

Given that gas continues to play a crucial role in balancing supply and demand for electricity, the options available to governments are limited, illustrating why rolling back electricity prices is harder than it appears for policymakers. One approach would be would be to keep faith with the liberalised market model, with limited interventions to help consumers in the short term, while ultimately relying on innovations in demand side technologies and alternatives to gas as a means of balancing systems with high shares of variable renewables.

An alternative scenario may see a return to old style national pricing policies, involving a move away from marginal pricing and spot markets, even as the EU prepares to revamp its electricity market in response. In the past, in particular during the post-WWII decades, and until markets were liberalised in the 1990s, governments have taken such an approach, centrally determining prices based on the costs of delivering long term system plans. The operation of gas plants and fuel procurement would become a much more regulated activity under such a model.

Many argue that this ‘traditional model’ better suits a world in which governments have committed to long-term decarbonisation targets, and zero marginal cost sources, such as wind and solar, play a more dominant role in markets and begin to push down prices.

A crucial question for energy policy makers is how to exploit this deflationary effect of renewables and pass-on cost savings to consumers, whilst ensuring that the lights stay on.

Despite the promise of storage technologies such as grid-scale batteries and hydrogen produced from electrolysis, aside from highly polluting coal, no alternative to internationally sourced natural gas as a means of balancing electricity systems and ensuring our energy security is immediately available.

This fact, above all else, will constrain the ambitions of governments to fundamentally transform energy markets.

Ronan Bolton is Reader at the School of Social and Political Science, University of Edinburgh and Co-Director of the UK Energy Research Centre. His book Making Energy Markets: The Origins of Electricity Liberalisation in Europe is to be published by Palgrave Macmillan in 2022.

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Everything Electric Vancouver spotlights EV innovation, electric vehicles, charging infrastructure, battery technology, autonomous driving, and sustainability, with test drives, consumer education, and incentives accelerating mainstream adoption and shaping the future of clean transportation.

Key Points

Everything Electric Vancouver is a premier EV expo for vehicles, charging tech, and clean mobility solutions.

✅ New EV models: better range, battery tech, autonomous features

✅ Focus on charging networks: ultra-fast and home solutions

✅ Consumer education: test drives, incentives, ownership costs

Vancouver has once again become the epicenter of electric vehicle (EV) innovation with the return of the "Everything Electric" event. This prominent showcase, as reported by Driving.ca, highlights the accelerating shift towards electric mobility, echoing momentum seen at the Quebec Electric Vehicle Show and the growing role of EVs in shaping the future of transportation. The event, held at the Vancouver Convention Centre, provided a comprehensive look at the latest advancements in electric vehicles, infrastructure, and technologies, drawing attention from industry experts, enthusiasts, and consumers alike.

A Showcase of Electric Mobility

"Everything Electric" has established itself as a key platform for unveiling new electric vehicles and technologies. This year’s event was no exception, featuring a diverse range of electric vehicles from leading manufacturers. Attendees had the opportunity to explore a wide array of models, from sleek sports cars and luxury sedans to practical SUVs and compact city cars. The showcase underscored the significant progress in EV design, performance, and affordability, reflecting a broader trend towards mainstream adoption of electric mobility.

One of the highlights of this year’s event was the unveiling of several cutting-edge electric models. Automakers used the platform to debut their latest innovations, including enhanced battery technologies, improved range capabilities, and advanced autonomous driving features. This not only demonstrated the rapid evolution of electric vehicles but also underscored the commitment of the automotive industry to addressing environmental concerns and meeting consumer demands for sustainable transportation solutions.

Expanding Charging Infrastructure

Beyond showcasing vehicles, "Everything Electric" also emphasized the critical role of charging infrastructure in supporting the growth of electric mobility. The event featured exhibits on the latest developments in charging technology, including ultra-fast chargers, innovative home charging solutions, and corridor networks such as B.C.'s Electric Highway that connect communities. With the increasing number of electric vehicles on the road, expanding and improving charging infrastructure is essential for ensuring convenience and reducing range anxiety among EV owners.

Industry experts and policymakers discussed strategies for accelerating the deployment of charging stations and integrating them into urban planning, while considering the B.C. Hydro bottleneck projections as demand grows. The event highlighted initiatives aimed at expanding public charging networks, particularly in underserved areas, and improving the overall user experience. As electric vehicles become more prevalent, the development of a robust and accessible charging infrastructure will be crucial for supporting their widespread adoption.

Driving Innovation and Sustainability

"Everything Electric" also served as a platform for discussions on the broader impact of electric vehicles on sustainability and innovation. Panels and presentations explored topics such as the environmental benefits of reducing greenhouse gas emissions, the role of renewable energy in powering EVs, insights from the evolution of U.S. EV charging infrastructure, and advancements in battery recycling and second-life applications. The event underscored the interconnected nature of electric mobility and sustainability, highlighting how innovations in one area can drive progress in others.

The emphasis on sustainability was evident throughout the event, with many exhibitors showcasing eco-friendly technologies and practices. From energy-efficient manufacturing processes to sustainable materials used in vehicle interiors, the event highlighted the automotive industry's efforts to reduce its environmental footprint and contribute to a more sustainable future.

Consumer Engagement and Education

A key aspect of "Everything Electric" was its focus on consumer engagement and education. The event offered test drives and interactive demonstrations, mirroring interest at the Regina EV event as well, allowing attendees to experience firsthand the benefits and performance of electric vehicles. This hands-on approach helped demystify electric mobility for many consumers and provided valuable insights into the practical aspects of owning and operating an EV.

In addition to vehicle demonstrations, the event featured workshops and informational sessions on topics such as EV financing, government incentives, and the benefits of transitioning to electric vehicles, reflecting how EVs in southern Alberta are a growing topic today. These educational opportunities were designed to empower consumers with the knowledge they need to make informed decisions about adopting electric mobility.

Looking Ahead

The successful return of "Everything Electric" to Vancouver highlights the growing importance of electric vehicles in the automotive landscape. As the event demonstrated, the electric vehicle market is rapidly evolving, with new technologies and innovations driving progress towards a more sustainable future. The increased focus on charging infrastructure, sustainability, and consumer education reflects a comprehensive approach to supporting the transition to electric mobility, exemplified by B.C.'s charging expansion across the province.

As Canada continues to advance its climate goals and promote sustainable transportation, events like "Everything Electric" play a crucial role in showcasing the possibilities and driving forward the adoption of electric vehicles. With ongoing advancements and increased consumer interest, the future of electric mobility in Vancouver and beyond looks increasingly promising.

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Ontario Renewable Energy Cancellations highlight Doug Ford's move to scrap wind turbine contracts, citing electricity rate relief and taxpayer savings, while critics, the NDP, and industry warn of job losses, termination fees, and auditor scrutiny.

Key Points

Ontario's termination of renewable contracts, defended as cost and rate relief, faces disputes over savings and jobs.

✅ PCs cite electricity rate relief and taxpayer savings.

✅ Critics warn of job losses and termination fees.

✅ Auditor inquiry sought into contract cancellation costs.

Ontario Premier Doug Ford, whose new stance on wind power has drawn attention, said Thursday he is “proud” of his decision to tear up hundreds of renewable energy deals, a move that his government acknowledges could cost taxpayers more than $230 million.

Ford dismissed criticism that his Progressive Conservatives are wasting public money, telling a news conference that the cancellation of 750 contracts signed by the previous Liberal government will save cash, even as Ontario moves to reintroduce renewable energy projects in the coming years.

“I’m so proud of that,” Ford said of his decision. “I’m proud that we actually saved the taxpayers $790 million when we cancelled those terrible, terrible, terrible wind turbines that really for the last 15 years have destroyed our energy file.”

Later Thursday, Ford went further in defending the cancelled contracts, saying “if we had the chance to get rid of all the wind mills we would,” though a court ruling near Cornwall challenged such cancellations.

The NDP first reported the cost of the cancellations Tuesday, saying the $231 million figure was listed as “other transactions”, buried in government documents detailing spending in the 2018-2019 fiscal year.

The Progressive Conservatives have said the final cost of the cancellations, which include the decommissioning of a wind farm already under construction in Prince Edward County, Ont., has yet to be established, amid warnings about wind project cancellation costs from developers.

The government has said it tore up the deals because the province didn’t need the power and it was driving up electricity rates, and the decision will save millions over the life of the contracts. Industry officials have disputed those savings, saying the cancellations will just mean job losses for small business, and ignore wind power’s growing competitiveness in electricity markets.

NDP Leader Andrea Horwath has asked Ontario’s auditor general to investigate the contracts and their termination fees, amid debates over Ontario’s electricity future among leadership contenders. She called Ford’s remarks on Thursday “ridiculous.”

“Every jurisdiction around the world is trying to figure out how to bring more renewables onto their electricity grids,” she said. “This government is taking us backwards and costing us at the very least $231 million in tearing these energy contracts.”

At the federal level, a recent green electricity contract with an Edmonton company underscores that shift.

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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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