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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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PG&E COVID-19 Shutoff Moratorium suspends service disconnections, offers flexible payment plans, and expands customer support with safety protocols, social distancing, and public health guidance for residential and commercial utility customers during the pandemic.

Key Points

A temporary halt to utility shutoffs with flexible payment plans to support PG&E customers during COVID-19.

✅ Suspends shutoffs for residential and commercial accounts

✅ Offers most flexible payment plans upon COVID-19 hardship

✅ Enhances safety: social distancing, PPE, remote work protocols

Pacific Gas and Electric Company has announced that due to the COVID-19 pandemic, it has voluntarily implemented a moratorium on service disconnections for non-payment, effective immediately. This suspension, similar to policies in New Jersey and New York, will apply to both residential and commercial customers and will remain in effect until further notice. To further support customers who may be impacted by the pandemic, PG&E will offer its most flexible pay plans to customers who indicate either an impact or hardship as a result of COVID-19. PG&E will continue to monitor current events and identify opportunities to support our customers and communities through concrete actions.

In addition to the moratorium on service shut-offs, PG&E’s response to the COVID-19 pandemic is focused on efforts to protect the health and safety of its customers, employees, contractors and the communities it serves, including ongoing wildfire risk reduction efforts that continue alongside its pandemic response. Actions the company has taken include providing guidance for employees who have direct customer contact to take social distancing precautionary measures, such as avoiding handshakes and wearing disposable nitrile gloves while in customers' homes, and continuing safety work related to power line-related fires across its service area.

Customers who visit local offices to pay bills and are sick or experiencing symptoms are being asked to use other payment options such as online or by phone, as seen when Texas utilities waived fees during the pandemic, at 1-877-704-8470.

“We recognize that this is a rapidly changing situation and an uncertain time for many of our customers. Our most important responsibility is the health and safety of our customers and employees. We also want to provide some relief from the stress and financial challenges many are facing during this worldwide, public health crisis, and with rates set to stabilize in 2025 the company remains focused on affordability. We understand that many of our customers may experience a personal financial strain due to the slowdown in the economy related to the pandemic, and programs like the Wildfire Assistance Program can help eligible customers,” said Chief Customer Officer and Senior Vice President Laurie Giammona.

Internally, the company is taking advanced cleaning measures, communicating best practices frequently with employees, and is asking its leaders to let employees work remotely if their job allows, while avoiding critical business disruption. PG&E has activated an enterprise-wide incident response team and is vigilantly monitoring the Centers for Disease Control and Prevention and World Health Organization for updates related to the virus. The company is committed to continue addressing customer service needs and does not expect any disruption in gas or electric service due to the public health crisis.

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TransAlta Alberta Data Centre integrates AI, cloud computing, and renewable energy, tackling electricity demand, grid capacity, decarbonization, and energy storage with clean power, cooling efficiency, and PPA-backed supply for hyperscale workloads.

Key Points

TransAlta Alberta Data Centre is a planned AI facility powered mostly by renewables to meet high electricity demand.

✅ Targets partner exclusivity mid-year; ops 18-24 months post-contract.

✅ Supplies ~90% power via TransAlta; balance from market.

✅ Anchors $3.5B clean energy growth and storage in Alberta.

TransAlta Corp., one of Alberta’s leading power producers, is moving toward finalizing agreements with partners to establish a data centre in the province, aligned with AI data center grid integration efforts nationally, aiming to have definitive contracts signed before the end of the year.

CEO John Kousinioris stated during an analyst conference that the company seeks to secure exclusivity with key partners by mid-year, with detailed design plans and final agreements expected by late 2025. Once the contracts are signed, the data centre is anticipated to be operational within 18 to 24 months, a horizon mirrored by Medicine Hat AI grid upgrades initiatives that aim to modernize local systems.

Data centres, which are critical for high-tech industries such as artificial intelligence, consume large amounts of electricity to run and cool servers, a trend reflected in U.S. utility power challenges reporting, underscoring the scale of energy demand. In this context, TransAlta plans to supply around 90% of its partner's energy needs for the facility, with the remainder coming from the broader electricity market.

Alberta has identified data centres as a strategic priority, aiming to see $100 billion in AI-related data centre construction over the next five years. However, the rapid growth of this sector presents challenges for the region’s energy infrastructure. Electricity demand from data centres has already outpaced the available capacity in Alberta’s power grid, intensifying discussions about a western Canadian electricity grid to improve regional reliability, potentially impacting the province’s decarbonization goals.

To address these challenges, TransAlta has adopted a renewable energy investment strategy. The company announced a $3.5 billion growth plan focused primarily on clean electricity generation and storage, as British Columbia's clean energy shift advances across the region, through 2028. By then, more than two-thirds of TransAlta’s earnings are expected to come from renewable power generation, supporting progress toward a net-zero electricity grid by 2050 nationally.

The collaboration between TransAlta and data centre developers represents an opportunity to balance growing energy demand with sustainability goals. By integrating renewable energy generation into data centre operations and broader macrogrid investments, Alberta could move toward a cleaner and more resilient energy future.

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We Energies rate increase driven by nuclear energy costs at Point Beach, Wisconsin PSC filings, and rising utility rates, affecting electricity prices for residential, commercial, and industrial customers while supporting WEC carbon reduction goals.

Key Points

A 2021 utility rate hike to recover Point Beach nuclear costs, modestly raising Wisconsin electricity bills.

✅ Residential bills rise about $0.73 per month

✅ Driven by $55.82/MWh Point Beach contract price

✅ PSC review and consumer advocates assessing alternatives

Wisconsin's largest utility company is again asking regulators to raise rates to pay for the rising cost of nuclear energy.

We Energies says it needs to collect an additional $26.5 million next year, an increase of about 3.4%.

For residential customers, that would translate to about 73 cents more per month, or an increase of about 0.7%, while some nearby states face steeper winter rate hikes according to regulators. Commercial and industrial customers would see an increase of 1% to 1.5%, according to documents filed with the Public Service Commission.

If approved, it would be the second rate increase in as many years for about 1.1 million We Energies customers, who saw a roughly 0.7% increase in 2020 after four years of no change, while Manitoba Hydro rate increase has been scaled back for next year, highlighting regional contrasts.

We Energies' sister utility, Wisconsin Public Service Corp., has requested a 0.13% increase, which would add about 8 cents to the average monthly residential bill, which went up 1.6% this year.

We Energies said a rate increase is needed to cover the cost of electricity purchased from the Point Beach nuclear power plant, which according to filings with the Securities Exchange Commission will be $55.82 per megawatt-hour next year.

So far this year, the average wholesale price of electricity in the Midwestern market was a little more than $25.50 per megawatt-hour, and recent capacity market payouts on the largest U.S. grid have fallen sharply, reflecting broader market conditions.

Owned and operated by NextEra Energy Resources, the 1,200-megawatt Point Beach Nuclear Plant is Wisconsin's last operational reactor. We Energies sold the plant for $924 million in 2007 and entered into a contract to purchase its output for the next two decades.

Brendan Conway, a spokesman for WEC Energy Group, said customers have benefited from the sale of the plant, which will supply more than a third of We Energies' demand and is a key component in WEC's strategy to cut 80% of its carbon emissions by 2050, amid broader electrification trends nationwide.

"Without the Point Beach plant, carbon emissions in Wisconsin would be significantly higher," Conway said.

As part of negotiations on its last rate case, WEC agreed to work with consumer advocates and the PSC to review alternatives to the contracted price increases, which were structured to begin rising steeply in 2018.

Tom Content, executive director of the Citizens Utility Board, said the contract will be an issue for We Energies customers into the next decade

"It's a significant source (of energy) for the entire state," Content said. "But nuclear is not cheap."

WEC filed the rate requests Monday, one week after the withdrawing similar applications. Conway said the largely unchanged filings had "undergone additional review by senior management."

WEC last week raised its second quarter profit forecast to 67 to 69 cents per share, up from the previous range of 58 to 62 cents per share.

The company credited better than expected sales in April and May along with operational cost savings and higher authorized profit margin for American Transmission Company, of which WEC is the majority owner.

Wisconsin's other investor-owned utilities have reported lower than expected fuel costs for 2020 and 2021, even as emergency fuel stock programs in New England are expected to cost millions this year.

Alliant Energy has proposed using about $31 million in fuel savings to help freeze rates in 2021, aligning with its carbon-neutral electricity plans as it rolls out long-term strategy, while Xcel Energy is proposing to lower its rates by 0.8% next year and refund its customers about $9.7 million in fuel costs for this year.

Madison Gas and Electric is negotiating a two-year rate structure with consumer groups who are optimistic that fuel savings can help prevent or offset rate increases, though some utilities are exploring higher minimum charges for low-usage customers to recover fixed costs.

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UK Peak Power Prices surged as low wind speeds forced National Grid to rely on gas-fired plants and coal generation, amid soaring wholesale gas prices and weak wind generation during the energy crisis.

Key Points

UK Peak Power Prices are electricity costs at peak hours, driven by wind output, gas reliance, and market dynamics.

✅ Spikes when wind generation drops and demand rises.

✅ Driven by gas-fired plants, coal backup, and wholesale gas prices.

✅ Moderate as wind output recovers and interconnectors supply.

Low wind speeds pushed peak hour power prices to the second highest level for at least three years on Monday, a move consistent with UK electricity prices hitting a 10-year high earlier this year, as Britain’s grid was forced to increase its reliance on gas-fired power plants and draw on coal generation.

Calm weather this year has exacerbated the energy price crisis in the UK, as gas-fired power stations have had to pick up the slack from wind farms. Energy demand has surged as countries open up from pandemic restrictions, which together with lower supplies from Russia to western Europe, has sent wholesale gas prices soaring.

Power prices in the UK for the peak evening period between 5pm and 6pm on Monday surpassed £2,000 per megawatt hour, only the second time they have exceeded that level in recent years.

This was still below the levels reached at the height of the gas price crisis in mid-September, when they hit £2,500/MWh, according to the energy consultancy Cornwall Insight, whose records date back to 2018.

Low wind speeds were the main driver behind Monday’s price spike, although expectations of a pick-up in wind generation on Tuesday, after recent record wind generation days, should push them back down to similar levels seen in recent weeks, analysts said.

Despite the expansion of renewables, such as wind and solar, over the past decade, with instances of wind leading the power mix in recent months, gas remains the single biggest source of electricity generation in Britain, typically accounting for nearly 40 per cent of output.

At lunchtime on Monday, gas-fired power plants were producing nearly 55 per cent of electricity, while coal accounted for 3 per cent, reflecting more power from wind than coal in 2016 milestones. Britain’s wind farms were contributing 1.67 gigawatts or just over 4 per cent, according to data from the Drax Electrics Insights website. Over the past 12 months, wind farms have produced 21 per cent of the UK’s electricity on average.

National Grid, which manages the UK’s electricity grid, has been forced on a number of occasions in recent months to ask coal plants to fire up to help offset the loss of wind generation, after issuing a National Grid short supply warning to the market. The government announced in June that it planned to bring forward the closure of the remaining coal stations to the end of September 2024.

Ministers also committed this year to making Britain’s electricity grid “net zero carbon” by 2035, and milestones such as when wind was the main source underline the transition, although some analysts have pointed out that would not signal the end of gas generation.

Since the start of the energy crisis in August, 20 energy suppliers have gone bust as they have struggled to secure the electricity and gas needed to supply customers at record wholesale prices, with further failures expected in coming weeks.

Phil Hewitt, director of the consultancy EnAppSys, said Monday’s high prices would further exacerbate pressures on those energy suppliers that do not have adequate hedging strategies. “This winter is a good time to be a generator,” he added.

Energy companies including Orsted of Denmark and SSE of the UK have reported some of the lowest wind speeds for at least two decades this year, even though record output during Storm Malik highlighted the system's volatility.

According to weather modelling group Vortex, the strength of the wind blowing across northern Europe has fallen by as much as 15 per cent on average in places this year, which some scientists suggest could be due to climate change.
 

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North Carolina Utility Arrears Crisis strains households and municipal budgets as COVID-19 cuts jobs; unpaid utility bills mount, shutoffs loom, and emergency aid, unemployment benefits, and CARES Act relief lag behind rising arrears across cities.

Key Points

A COVID-19 driven spike in unpaid utility bills, threatening households and municipal budgets as federal aid lapses.

✅ 1 million families behind on power, water, sewage bills

✅ $218M arrears accrued April to June, double last year

✅ Municipal utilities face shutoffs, budget shortfalls

As many as 1 million families in North Carolina have fallen behind on their electric, water and sewage bills, a sign of energy insecurity threatening residents and their cities with severe financial hardship unless federal lawmakers act to approve more emergency aid.

The trouble stems from the widespread economic havoc wrought by the coronavirus, which has left millions of workers out of a job and struggling to cover their monthly costs as some states moved to suspend utility shut-offs to provide relief. Together, they’ve been late or missed a total of $218 million in utility payments between April 1 and the end of June, according to data released recently by the state, nearly double the amount in arrears at this time last year.

In some cases, cities that own or operate their own utilities have been forced to absorb these losses, as some utilities reconnected customers to prevent harm, creating a dire situation in which the government’s attempt to save people from the financial brink instead has pushed municipal coffers to their own breaking point.

In Elizabeth City, N.C., for example, about 2,500 residents haven’t paid their electric bills on time, according to Richard Olson, the city manager. The late payments at one point proved so problematic that Olson said he calculated Elizabeth City wouldn’t have enough money to pay for its expenses in July. In response, city leaders requested and obtained a waiver from a statewide order, similar to New York’s disconnection moratorium, issued in March, that protects people from being penalized for their past-due utility bills.

The predicament has presented unique budget challenges throughout North Carolina, while illustrating the consequences of a cash crunch plaguing the entire country, where proposals such as a Texas electricity market bailout surfaced following severe grid stress. State and federal leaders have extended a range of coronavirus relief programs since March to try to help people through the pandemic. But the money is limited and restricted — and it’s not clear whether more help from Congress is on the way — creating a crisis in which the nation’s economic woes are outpacing some of the aid programs adopted to combat them.

“We are entering a phase where the utilities [may] be able to shut off power, but what was propping up people’s economic lives, the unemployment benefits and Cares Act support, won’t be there,” said Paul Meyer, the executive director of the North Carolina League of Municipalities.

White House, GOP in disarray over coronavirus spending plan as deadline nears on expiring emergency aid

The future of that safety-net support — and other federal aid — hangs in the balance as lawmakers returned to work this week in their final sprint ahead of the August recess. The White House and congressional leaders are split over the contours of the next coronavirus relief package, including the need to extend more aid to cities and states as some utilities have waived fees to help customers, and reauthorize an extra $600 in weekly unemployment payments that were approved as part of the Cares Act in March.

Outside Washington, workers, businesses and government officials nationwide have pleaded with federal lawmakers to renew or expand those programs. Last week, Roy Cooper, the Democratic governor of North Carolina, urged Congress to act swiftly and adopt a wide array of new federal spending, including proposals for DOE nuclear cleanup funding, stressing in a letter that the “actions you take in the next few weeks are vital to our ability to emerge from this crisis. ”

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