Going tankless to save energy

Near-Field Thermophotovoltaics captures radiated energy across a nanoscale gap, using thin-film photovoltaic cells and indium gallium arsenide to boost power density and efficiency, enabling compact Army portable power from emitters via radiative heat transfer.

Key Points

A nanoscale TPV method capturing near-field photons for higher power density at lower emitter temperatures.

✅ Nanoscale gap boosts radiative transfer and usable photon flux

✅ Thin-film InGaAs cells recycle sub-band-gap photons via reflector

✅ Achieved ~5 kW/m2 power density with higher efficiency

With the addition of sensors and enhanced communication tools, providing lightweight, portable power has become even more challenging, with concepts such as power from falling snow illustrating how diverse new energy-harvesting approaches are. Army-funded research demonstrated a new approach to turning thermal energy into electricity that could provide compact and efficient power for Soldiers on future battlefields.

Hot objects radiate light in the form of photons into their surroundings. The emitted photons can be captured by a photovoltaic cell and converted to useful electric energy. This approach to energy conversion is called far-field thermophotovoltaics, or FF-TPVs, and has been under development for many years; however, it suffers from low power density and therefore requires high operating temperatures of the emitter.

The research, conducted at the University of Michigan and published in Nature Communications, demonstrates a new approach, where the separation between the emitter and the photovoltaic cell is reduced to the nanoscale, enabling much greater power output than what is possible with FF-TPVs for the same emitter temperature.

This approach, which enables capture of energy that is otherwise trapped in the near-field of the emitter is called near-field thermophotovoltaics or NF-TPV and uses custom-built photovoltaic cells and emitter designs ideal for near-field operating conditions, alongside emerging smart solar inverters that help manage conversion and delivery.

This technique exhibited a power density almost an order of magnitude higher than that for the best-reported near-field-TPV systems, while also operating at six-times higher efficiency, paving the way for future near-field-TPV applications, including remote microgrid deployments in extreme environments, according to Dr. Edgar Meyhofer, professor of mechanical engineering, University of Michigan.

"The Army uses large amounts of power during deployments and battlefield operations and must be carried by the Soldier or a weight constrained system," said Dr. Mike Waits, U.S. Army Combat Capabilities Development Command's Army Research Laboratory. "If successful, in the future near-field-TPVs could serve as more compact and higher efficiency power sources for Soldiers as these devices can function at lower operating temperatures than conventional TPVs."

The efficiency of a TPV device is characterized by how much of the total energy transfer between the emitter and the photovoltaic cell is used to excite the electron-hole pairs in the photovoltaic cell, where insights from near-light-speed conduction research help contextualize performance limits in semiconductors. While increasing the temperature of the emitter increases the number of photons above the band-gap of the cell, the number of sub band-gap photons that can heat up the photovoltaic cell need to be minimized.

"This was achieved by fabricating thin-film TPV cells with ultra-flat surfaces, and with a metal back reflector," said Dr. Stephen Forrest, professor of electrical and computer engineering, University of Michigan. "The photons above the band-gap of the cell are efficiently absorbed in the micron-thick semiconductor, while those below the band-gap are reflected back to the silicon emitter and recycled."

The team grew thin-film indium gallium arsenide photovoltaic cells on thick semiconductor substrates, and then peeled off the very thin semiconductor active region of the cell and transferred it to a silicon substrate, informing potential interfaces with home battery systems for distributed use.

All these innovations in device design and experimental approach resulted in a novel near-field TPV system that could complement distributed resources in virtual power plants for resilient operations.

"The team has achieved a record ~5 kW/m2 power output, which is an order of magnitude larger than systems previously reported in the literature," said Dr. Pramod Reddy, professor of mechanical engineering, University of Michigan.

Researchers also performed state-of-the-art theoretical calculations to estimate the performance of the photovoltaic cell at each temperature and gap size, informing hybrid designs with backup fuel cell solutions that extend battery life, and showed good agreement between the experiments and computational predictions.

"This current demonstration meets theoretical predictions of radiative heat transfer at the nanoscale, and directly shows the potential for developing future near-field TPV devices for Army applications in power and energy, communication and sensors," said Dr. Pani Varanasi, program manager, DEVCOM ARL that funded this work.

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Doug Ford's Hydro One firing vow targets CEO pay, the utility's board, and privatization, amid Ontario politics over electricity rates, governance, and control, raising questions about legal tools, contracts, and impacts on customers and taxpayers.

Key Points

Ford vows to oust Hydro One's CEO and board to curb pay and signal rate restraint, subject to legal and governance limits.

✅ Province lacks direct control post-privatization

✅ Possible board removals to influence executive pay

✅ Impact on rates, contracts, and shareholders unclear

Ontario PC Leader Doug Ford is vowing to fire the head of Hydro One, and its entire board if he's elected premier in June.

Ford made the announcement, calling President and CEO Mayo Schmidt, Premier "Kathleen Wynne's $6-Million dollar man," referring to his yearly salary and bonuses, which now add up to $6.2 million.

"This board and this CEO are laughing themselves to the bank," Ford said.

However, it's unclear how Ford would do that since the province does not control the company anymore.

"We don't have the ability to go out and say we are firing the CEO at Hydro One," PC energy critic Todd Smith said while speaking to reporters after Ford's remarks.

#google#

However, he said "we do have tools at our disposal in the tool box. The unfortunate thing is that Kathleen Wynne and the Liberals have just let those tools sit there for the last couple of years and [have] not taken action on things like this."

Smith declined to provide details about what those tools are, but suggested Ford would have the right to fire Hydro's board.

He said that would send a message "that we're not going to accept these salaries."

Smith says the Ontario gov still has the right to fire Hydro One board. What about their contracts? Pay them out? Smith says they don't know the details of people's contacts

We will not engage in politics,' Hydro One says

A Hydro One spokesperson said the amount customers pay to compensate the CEO's salary is the same as before privatization — two cents on each monthly bill.

"We will not engage in politics, however our customers deserve the facts," said the email statement to CBC Toronto.

"Nearly 80 per cent of the total executive compensation package is paid for by shareholders."

Ontario NDP MPP Peter Tabuns says Ford is pro-privatization, and that won't help those struggling with high hydro bills. (Michelle Siu/The Canadian Press)

Peter Tabuns, the NDP's energy critic, said his government would aim to retake public control of Hydro One to cap CEO pay and control the CEO's "outrageous salary."

But while he shares Ford's goal of cutting Schmidt's pay, Tabuns blasted what he believes would be the PC leader's approach.

"Doug Ford has no idea how to reign [sic] in the soaring hydro bills that Ontario families are facing — in fact, if his threats of further privatization include hydro, he'll drive bills and executive salaries ever higher," he said in an email statement.

The only plan we've heard from Doug Ford so far is firing people and laying off people.- Glenn Thibeault, Energy Minister

​Tabuns says his party would aim to cut hydro bills by 30 per cent.

Meanwhile, Liberal Energy Minister Glenn Thibeault said Ford's plan will do nothing to address the actual issue of keeping hydro rates low, comparing his statement Thursday to the rhetoric and actions of U.S. President Donald Trump.

"The only plan we've heard from Doug Ford so far is firing people and laying off people," Thibeault said.

"What I'm seeing a very strong prevalence to is the person running the White House. He's been doing a lot of firing as well and that's not been working out so well for them."

Wynne government has taken steps to cut hydro bills, including legislation to lower electricity rates in Ontario.

Hydro prices have shot up in recent years prompting criticism from across Ontario. Wynne made the controversial move of privatizing part of the utility beginning in 2015.

By Oct. 2017, the Ontario Liberal government's "Fair Hydro Plan" had brought down the average household electricity bill by a 25% rate cut from the peak it hit in the summer of 2016. The Wynne government has also committed to keep rate increases below inflation for the next four years, but admits bills will rise significantly in the decade that follows as a recovery rate could drive costs higher.

Ford blasted the government's moves during a Toronto news conference, echoing calls to scrap the Fair Hydro Plan and review other options.

"The party's over with the tax payer's money, we're going to start respecting the tax payers," Ford said, repeatedly saying the money spent on Hydro One salaries is "morally indefensible."

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U.S. Solar Generation 2017 surpassed biomass, delivering 77 million MWh versus 64 million MWh, trailing only hydro and wind; driven by PV expansion, capacity additions, and utility-scale and small-scale growth, per EIA.

Key Points

It was the year U.S. solar electricity exceeded biomass, hitting 77 million MWh and trailing only hydro and wind.

✅ Solar: 77 million MWh; Biomass: 64 million MWh (2017, EIA)

✅ PV expansion; late-year capacity additions dampen annual generation

✅ Hydro: 300 and wind: 254 million MWh; solar thermal ~3 million MWh

Electricity generation from solar resources in the United States reached 77 million megawatthours (MWh) in 2017, surpassing for the first time annual generation from biomass resources, which generated 64 million MWh in 2017. Among renewable sources, only hydro and wind generated more electricity in 2017, at 300 million MWh and 254 million MWh, respectively. Biomass generating capacity has remained relatively unchanged in recent years, while solar generating capacity has consistently grown.

Annual growth in solar generation often lags annual capacity additions because generating capacity tends to be added late in the year. For example, in 2016, 29% of total utility-scale solar generating capacity additions occurred in December, leaving few days for an installed project to contribute to total annual generation despite being counted in annual generating capacity additions. In 2017, December solar additions accounted for 21% of the annual total. Overall, solar technologies operate at lower annual capacity factors and experience more seasonal variation than biomass technologies.

Biomass electricity generation comes from multiple fuel sources, such as wood solids (68% of total biomass electricity generation in 2017), landfill gas (17%), municipal solid waste (11%), and other biogenic and nonbiogenic materials (4%).These shares of biomass generation have remained relatively constant in recent years, even as renewables' rise in 2020 across the grid.

Solar can be divided into three types: solar thermal, which converts sunlight to steam to produce power; large-scale solar photovoltaic (PV), which uses PV cells to directly produce electricity from sunlight; and small-scale solar, which are PV installations of 1 megawatt or smaller. Generation from solar thermal sources has remained relatively flat in recent years, at about 3 million MWh, even as renewables surpassed coal in 2022 nationwide. The most recent addition of solar thermal capacity was the Crescent Dunes Solar Energy plant installed in Nevada in 2015, and currently no solar thermal generators are under construction in the United States.

Solar photovoltaic systems, however, have consistently grown in recent years, as indicated by 2022 U.S. solar growth metrics across the sector. In 2014, large-scale solar PV systems generated 15 million MWh, and small-scale PV systems generated 11 million MWh. By 2017, annual electricity from those sources had increased to 50 million MWh and 24 million MWh, respectively, with projections that solar could reach 20% by 2050 in the U.S. mix. By the end of 2018, EIA expects an additional 5,067 MW of large-scale PV to come online, according to EIA’s Preliminary Monthly Electric Generator Inventory, with solar and storage momentum expected to accelerate. Information about planned small-scale PV systems (one megawatt and below) is not collected in that survey.

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Nordic Power Grid Dispute highlights cross-border interconnector congestion, curtailed exports and imports, hydropower priorities, winter demand spikes, rising spot prices, and transmission grid security amid decarbonization efforts across Sweden, Norway, Finland, and Denmark.

Key Points

A clash over interconnectors and capacity cuts reshaping trade, prices, and reliability in the Nordic power market.

✅ Sweden cuts interconnector capacity to protect grid stability

✅ Norway prioritizes higher-priced exports via new cables

✅ Finland and Denmark seek EU action on capacity curtailments

A spat over electricity supplies is heating up in northern Europe. Sweden is blocking Norway from using its grids to transfer power from producers throughout the region. That’s angered Norway, which in turn has cut flows to its Nordic neighbor.

The dispute has built up around the use of cross-border power cables, which are a key part of Europe’s plans to decarbonize since they give adjacent countries access to low-carbon resources such as wind or hydropower. The electricity flows to wherever prices are higher, informed by how electricity is priced across Europe, without interference from grid operators -- but in the event of a supply squeeze, flows can be stopped.

Sweden moved to safeguard the security of its grid after Norway started increasing electricity exports through huge new cables to Germany and the U.K. Those exports at times have drawn energy away from Sweden, resulting in the country’s system operator cutting capacity at its Nordic borders, preventing exports but also hindering imports, which it relies on to handle demand spikes during winter.

“This is not a good situation in the long run,” Christian Holtz, a energy market consultant for Merlin & Metis AB.

Norway hit back last week by cutting flows to Sweden, this will prioritize better paying customers in Europe, amid Irish price spikes that highlight dispatchable shortages, giving them access to its vast hydro resources at the expense of its Nordic neighbors. 

By partially closing its borders Sweden can’t access imports either, which it relies on to handle demand spikes during the coldest days of the winter. 

In Denmark, unusual summer and autumn winds have at times delivered extraordinarily low electricity prices that ripple through regional markets.

The Swedish grid manager Svenska Kraftnat has reduced export capacity at cables across its borders by as much as half this year to keep operations secure. Finland and Denmark rely on imports too and the cuts will come at a cost for millions of homes and industries across the four nations already contending with record electricity rates this year. 

Finland and Denmark want the European Union to end the exemption to regulations that make such reductions possible in the first place, as Europe is losing nuclear power and facing tighter supply.

“Imports from our neighboring countries ensure adequacy at times of peak consumption,” said Reima Paivinen, head of operation at the Finland’s Fingrid. “The recent surge in electricity prices throughout Europe does not directly affect the adequacy of electricity, but prices may rise dramatically for short periods.”

Svenska Kraftnat says it’s not political -- it has no choice but to cut capacity until its old grids are expanded to handle the new direction of flows, a challenge mirrored by grid expansion woes in Germany that slow integration. That could take at least until 2030 to complete, it said earlier this year. At the same time, Norway halving available export capacity to about 1,200 megawatts will increase risk of shortages. 

“If we need more we will have to count on imports from other countries,” said Erik Ek, head of strategic operation at Svenska Kraftnat. “If that is not available, we will have to disconnect users the day it gets cold.”

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UK Energy Price Cap aims to protect consumers on gas and electricity bills, tackling Big Six overcharging on default and standard variable tariffs, with Ofgem and MPs pushing urgent reforms to the broken market.

Key Points

A temporary absolute limit on default energy tariffs to shield consumers from overcharging on gas and electricity bills.

✅ Caps standard variable and default tariffs to protect loyalty.

✅ Targets Big Six pricing; oversight by Ofgem and BEIS MPs.

✅ Aims for winter protection while maintaining competition.

MPs are calling for a cap on the price of gas and electricity, with questions over the expected cost of a UK price cap amid fears consumers are being ripped off.

The Business, Energy and Industrial Strategy (BEIS) Select Committee says the Big Six energy companies have been overcharging for years.

MPs on the committee backed plans for a temporary absolute cap, noting debates over EU gas price cap strategies to fix what they called a "broken" energy market.

Labour's Rachel Reeves, who chairs the committee, said: "The energy market is broken. Energy is an essential good and yet millions of customers are ripped off for staying loyal to their energy provider.

"An energy price cap is now necessary and the Government must act urgently to ensure it is in place to protect customers next winter.

"The Big Six energy companies might whine and wail about the introduction of a price cap but they've been overcharging their customers on default and SVTs (standard variable tariffs) for years and their recent feeble efforts to move consumers off these tariffs has only served to highlight the need for this intervention."

The Committee also criticised Ofgem for failing to protect customers, especially the most vulnerable.

Draft legislation for an absolute cap on energy tariffs was published by the Government last year, and later developments like the Energy Security Bill have kept reform on the agenda.

But Business Secretary Greg Clark refused to guarantee that the flagship plans would be in place by next winter, despite warnings about high winter energy costs for households.

Committee members said there was a "clear lack of will" on the part of the Big Six to do what was necessary, including exploring decoupling gas and electricity prices, to deal with pricing problems.

A report from the committee found that customers are paying £1.4bn a year more than they should be under the current system.

Around 12 million households are stuck on poor-value tariffs, according to the report.

National assistance charity Citizens Advice said "loyal and vulnerable" customers had been "ripped off" for too long.

Chief executive Gillian Guy said: "An absolute cap, as recommended by the committee, is crucial to securing protection for the largest number of customers while continuing to provide competition in the market. This should apply to all default tariffs."

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Calgary Electricity Price Increase signals higher ENMAX bills as grid demand surges; wholesale market volatility, fixed vs floating rates, kWh costs, and transmission charges drive above-average pricing across Alberta this winter.

Key Points

A market-led rise in Calgary power rates as grid demand and wholesale volatility affect fixed and floating plans.

✅ ENMAX warns of higher winter prices amid record grid demand

✅ Fixed rates hedge wholesale volatility; floating tracks spot market

✅ Transmission and distribution fees rise 5-10 percent annually

Calgarians should expect to be charged more for their electricity bills amid significant demand on the grid and a transition to above-average rates across Alberta.

ENMAX, one of the most-used electricity providers in the city, has sent an email to customers notifying them of higher prices for the rest of the winter months.

“Although fluctuations in electricity market prices are normal, we have seen a general trend of increasing rates over time,” the email to customers read.

“The price volatility we are forecasting is due to market factors beyond a single energy provider, including but not limited to expectations for a colder-than-normal winter and changes in electricity supply and demand in Alberta’s wholesale market. ”

Earlier this month, the province set a record for electricity usage during a bitterly cold stretch of weather.

According to energy comparison website energyrates.ca, Alberta’s energy prices have increased by 34 per cent between November 2020 and 2021.

“One of the reasons that this increase seems so significant is we’re actually coming off of a low period in the market,” the site’s founder Joel MacDonald told Global News. “You’re seeing rates well below average transitioning to well above average.”

According to ENMAX’s rate in January, the price of electricity currently sits at 15.9 cents per kilowatt-hour, with an electricity price spike from 7.9 cents per kilowatt-hour last year.

MacDonald said prices for electricity have been relatively low since 2018 but a swing in the price of oil has created more activity in the province’s industrial sector, and in turn more demand on the power grid.

According to MacDonald, the price increase can also be attributed to the removal of a consumer price cap that limited regulated rates to 6.8 cents per kilowatt-hour for households and small businesses with lower demand, which, after the carbon tax was repealed, initially remained in place.

Although the cap was scrapped by the UCP three years ago, he said energy bills now depend on the rate set by the market.

“What’s increased now recently is actually the price per kilowatt, and the (transmission and distribution) charges have only increased, but annually they increase between five and 10 per cent,” MacDonald said. “So the portion of your bill that’s increasing is different than what Albertans are typically used to, or at least in recent memory.”

But Albertans do have options, MacDonald said.

As part of its email to customers, ENMAX sent a list of energy saving tips to reduce energy consumption in people’s homes, including using cold water for laundry and avoiding dryer use, energy-efficient lightbulbs and unplugging electronics when they are not in use.

Retailers also offer contracts with floating or fixed rates for consumers.

“Fixed rates, obviously, you’re going to pick your price. It’s going to be the same each and every single month,” MacDonald said. “Floating rate is based off the wholesale spot market, and that has been exceptionally high the last few months.”

He said consumers looking to save money when electricity prices are high should look into a fixed rate.

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