California ISO will help track renewable 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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National Grid power supply warning highlights electricity shortage risks amid low wind output, generator outages, and cold weather, reducing capacity margins and grid stability; considering demand response and reserve power to avoid blackout risk.

Key Points

An alert that reduced capacity from low wind and outages requires actions to maintain UK grid stability.

✅ Low wind output and generator outages reduce capacity margins

✅ ESO exploring demand response and reserve generation options

✅ Aim: maintain grid stability and avoid blackout risk

National Grid has warned that Britain’s electricity will be in short supply over the next few days after a string of unplanned power plant outages and unusually low wind speeds this week, as cheap wind power wanes across the system.

The electricity system operator said it will take action to “make sure there is enough generation” during the cold weather spell, including virtual power plants and other demand-side measures, to prevent a second major blackout in as many years.

“Unusually low wind output coinciding with a number of generator outages means the cushion of spare capacity we operate the system with has been reduced,” the company told its Twitter followers.

“We’re exploring measures and actions to make sure there is enough generation available to increase our buffer of capacity.”

A spokeswoman for National Grid said the latest electricity supply squeeze was not expected to be as severe as recorded last month, following reports that the government’s emergency energy plan was not going ahead, and added that the company did not expect to issue an official warning in the next 24 hours.

“We’re monitoring how the situation develops,” she said.

The warning is the second from the electricity system operator in recent weeks. In mid-September the company issued an official warning to the electricity market as peak power prices climbed, that its ‘buffer’ of power reserves had fallen below 500MW and it may need to call on more power plants to help prevent a blackout. The notice was later withdrawn.

Concerns over National Grid’s electricity supplies have been relatively rare in recent years. It was forced in November 2015 to ask businesses to cut their demand as a “last resort” measure to keep the lights on after a string of coal plant breakdowns.

But since then, National Grid’s greater challenge has been an oversupply of electricity, partly due to record wind generation, which has threatened to overwhelm the grid during times of low electricity demand.

National Grid has already spent almost £1bn on extra measures to prevent blackouts over the first half of the year by paying generators to produce less electricity during the coronavirus lockdown, as daily demand fell.

The company paid wind farms to turn off, and EDF Energy to halve the nuclear generation from its Sizewell B nuclear plant, to avoid overwhelming the grid when demand for electricity fell by almost a quarter from last year.

The electricity supply squeeze comes a little over a year after National Grid left large parts of England and Wales without electricity after the biggest blackout in a decade left a million homes in the dark. National Grid blamed a lightning strike for the widespread power failure.

Similar supply strains have recently caused power cuts in China, underscoring how weather and generation mix can trigger blackouts.

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Brazil ICMS Tax Cap limits state VAT on fuels, natural gas, electricity, communications, and transit, promising short-term price relief amid inflation, with federal compensation to states and potential legal challenges affecting investments and ANP auctions.

Key Points

A policy capping state VAT at 17-18 percent on fuels, electricity, and services to temper prices and inflation.

✅ Caps VAT to 17-18% on fuels, power, telecom, transit

✅ Short-term relief; medium-long term impact uncertain

✅ Federal compensation; potential court challenges, investment risk

Brazil’s congress approved a bill that limits the ICMS tax rate that state governments can charge on fuels, natural gas, electricity, communications, and public transportation. 

Local lawyers told BNamericas that the measure may reduce fuel and power prices in the short term, similar to Brazil power sector relief loans seen during the pandemic, but it is unlikely to produce any major effects in the medium and long term. 

In most states the ceiling was set at 17% or 18% and the federal government will pay compensation to the states for lost tax revenue until December 31, via reduced payments on debts that states owe the federal government.

The bill will become law once signed by President Jair Bolsonaro, who pushed strongly for the proposal with an eye on his struggling reelection campaign for the October presidential election. Double-digit inflation has turned into a major election issue and fuel and electricity prices have been among the main inflation drivers, as seen in EU energy-driven inflation across the bloc this year. Congress’ approval of the bill is seen by analysts as political victory for the Brazilian leader.

How much difference will it make?

Marcus Francisco, tax specialist and partner at Villemor Amaral Advogados, said that in the formation of fuel and electricity prices there are other factors, including high natural gas prices, that drive increases.

“In the case of fuels, if the barrel of oil [price] increases, automatically the final price for the consumer will go up. For electricity, on the other hand, there are several subsidies and policy choices such as Florida rejecting federal solar incentives that are part of the price and that can increase the rate [paid],” he said. 

There is also a possibility that some states will take the issue to the supreme court since ICMS is a key source of revenue for them, Francisco added.

Tiago Severini, a partner at law firm Vieira Rezende, said the comparison between the revenue impact and the effective price reduction, based on the estimates made by the states and the federal government, seems disproportionate, and, as seen in Europe, rolling back European electricity prices is often tougher than it appears. 

“In other words, a large tax collection impact is generated, which is quite unequal among the different states, for a not so strong price reduction,” he said.

“Due to the lack of clarity regarding the precision of the calculations involved, it’s difficult even to assess the adequacy of the offsets the federal government has been considering, and international cases such as France's new electricity pricing scheme illustrate how complex it can be to align fiscal offsets with regulatory constraints, to cover the cost it would have with the compensation for the states” Severini added.

The compensation ideas that are known so far include hiking other taxes, such as the social contribution on net profits (CSLL) that is paid by oil and gas firms focused on exploration and production.

“This can generate severe adverse effects, such as legal disputes, reduced investments in the country, and reduced attractiveness of the new auctions by [sector regulator] ANP, and costly interventions like the Texas electricity market bailout after extreme weather events,” Severini said. 

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U.S. Utility Spending Shift highlights rising transmission and distribution costs, grid modernization, and smart meters, while generation expenses decline amid fuel price volatility, capital and labor pressures, and renewable integration across the power sector.

Key Points

A decade-long trend where utilities spend more on delivery and grid upgrades, and less on electricity generation costs.

✅ Delivery O&M, wires, poles, and meters drive rising costs

✅ Generation spending declines amid fuel price changes and PPI

✅ Grid upgrades add reliability, resilience, and renewable integration

Over the past decade, major utilities in the United States have been spending more on delivering electricity to customers and less on producing that electricity, a shift occurring as electricity demand is flat across many regions.

After adjusting for inflation, major utilities spent 2.6 cents per kilowatthour (kWh) on electricity delivery in 2010, using 2020 dollars. In comparison, spending on delivery was 65% higher in 2020 at 4.3 cents/kWh, and residential bills rose in 2022 as inflation persisted. Conversely, utility spending on power production decreased from 6.8 cents/kWh in 2010 (using 2020 dollars) to 4.6 cents/kWh in 2020.

Utility spending on electricity delivery includes the money spent to build, operate, and maintain the electric wires, poles, towers, and meters that make up the transmission and distribution system. In real 2020 dollar terms, spending on electricity delivery increased every year from 1998 to 2020 as utilities worked to replace aging equipment, build transmission infrastructure to accommodate new wind and solar generation amid clean energy transition challenges that affect costs, and install new technologies such as smart meters to increase the efficiency, reliability, resilience, and security of the U.S. power grid.

Spending on power production includes the money spent to build, operate, fuel, and maintain power plants, as well as the cost to purchase power in cases where the utility either does not own generators or does not generate enough to fulfill customer demand. Spending on electricity production includes the cost of fuels including natural gas prices alongside capital, labor, and building materials, as well as the type of generators being built.

Other utility spending on electricity includes general and administrative expenses, general infrastructure such as office space, and spending on intangible goods such as licenses and franchise fees, even as electricity sales declined in recent years.

The retail price of electricity reflects the cost to produce and deliver power, the rate of return on investment that regulated utilities are allowed, and profits for unregulated power suppliers, and, as electricity prices at 41-year high have been reported, these components have drawn increased scrutiny.

In 2021, demand for consumer goods and the energy needed to produce them has been outpacing supply, though power demand sliding in 2023 with milder weather has also been noted. This difference has contributed to higher prices for fuels used by electric generators, especially natural gas. The increased cost for fuel, capital, labor, and building materials, as seen in the U.S. Bureau of Labor Statistics’ Producer Price Index, is increasing the cost of power production for 2021. U.S. average electricity prices have been higher every month of this year compared with 2020, according to our Monthly Electric Power Industry Report.

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Ukraine Winter Energy Strategy strengthens the power grid through infrastructure repairs, electricity imports, renewable integration, nuclear output, and conservation to ensure reliable heating, blackout mitigation, and grid resilience with international aid, generators, and transmission lines.

Key Points

A wartime plan to stabilize Ukraine's grid via repairs, imports, renewables, and nuclear to deliver reliable electricity.

✅ Repairs, imports, and demand management stabilize the grid.

✅ Renewables and nuclear reduce outage risks in winter.

✅ International aid supplies transformers, generators, expertise.

As Ukraine braces for the winter months, the question of how the country will keep the lights on has become a pressing concern, as the country fights to keep the lights on amid ongoing strikes. The ongoing war with Russia has severely disrupted Ukraine's energy infrastructure, leading to widespread damage to power plants, transmission lines, and other critical energy facilities. Despite these challenges, Ukraine has been working tirelessly to maintain its energy supply during the cold winter months, which are essential not only for heating but also for the functioning of homes, businesses, hospitals, and schools. Here's a closer look at the steps Ukraine is taking to keep the lights on this winter and ensure that its people have access to reliable electricity.

1. Repairing Damaged Infrastructure

One of the most immediate concerns for Ukraine's energy sector is the extensive damage inflicted on its power infrastructure by Russian missile and drone attacks. Since the war began in 2022, Ukraine has faced repeated attacks targeting power plants, substations, and power lines, including strikes on western regions that caused widespread outages across communities. These attacks have left parts of the country with intermittent or no electricity, and repairing the damage has been a monumental task.

However, Ukraine has made significant progress in restoring its energy infrastructure. Government agencies and energy companies have been working around the clock to repair power plants and transmission networks. Teams of technicians and engineers have been deployed to restore power to areas that have been hardest hit by Russian attacks, often under difficult and dangerous conditions. While some areas may continue to face outages, efforts to rebuild the energy grid are ongoing, with the government prioritizing critical infrastructure to ensure that hospitals, military facilities, and essential services have access to power.

2. Energy Efficiency and Conservation Measures

To cope with reduced energy availability and avoid overloading the grid, Ukrainian authorities have been encouraging energy efficiency and conservation measures. These efforts are particularly important during the winter when demand for electricity and heating is at its peak.

The government has implemented energy-saving programs, urging citizens and businesses to reduce their consumption and adopt new energy solutions that can be deployed quickly. Measures include limiting electricity use during peak hours, setting thermostats lower in homes and businesses, and encouraging the use of energy-efficient appliances. Ukrainian officials have also been promoting public awareness campaigns to educate people about the importance of energy conservation, which is crucial to avoid grid overload and ensure the distribution of power across the country.

3. Importing Energy from Abroad

To supplement domestic energy production, Ukraine has been working to secure electricity imports from neighboring countries. Ukraine has long been interconnected with energy grids in countries such as Poland, Slovakia, and Hungary, which allows it to import electricity during times of shortage. In recent months, Ukraine has ramped up efforts to strengthen these connections, ensuring that it can import electricity when domestic production is insufficient to meet demand, and in a notable instance, helped Spain during blackouts through coordinated cross-border support.

While electricity imports from neighboring countries provide a temporary solution, this is not without its challenges. The cost of importing electricity can be high, and the country’s ability to import large amounts of power depends on the availability of energy in neighboring nations; officials say there are electricity reserves and no scheduled outages if strikes do not resume. Ukraine has been actively seeking new energy partnerships and working with international organizations to secure access to electricity, including exploring the potential for importing energy from the European Union.

4. Harnessing Renewable Energy Sources

Another key part of Ukraine's strategy to keep the lights on this winter is tapping into renewable energy sources, particularly wind and solar power. While Ukraine’s energy sector has historically been dependent on fossil fuels, the country has been making strides in integrating renewable energy into its grid. Solar and wind energy are particularly useful in supplementing the national grid, especially during the winter months when demand is high.

Renewable energy sources are less vulnerable to missile strikes compared to traditional power plants, making them an attractive option for Ukraine's energy strategy. Although renewable energy currently represents a smaller portion of Ukraine’s overall energy mix, its contribution is expected to increase as the country invests more in clean energy infrastructure. In addition to reducing dependence on fossil fuels, this shift is aligned with Ukraine’s broader environmental goals and will be important for the long-term sustainability of its energy sector.

5. International Aid and Support

International support has been crucial in helping Ukraine keep the lights on during the war. Western allies, including the European Union and the United States, have provided financial assistance, technical expertise, and equipment to help restore the energy infrastructure, though Washington recently ended some grid restoration support as priorities shifted. In addition to rebuilding power plants and transmission lines, Ukraine has received advanced energy technologies and materials to strengthen its energy security.

The U.S. has sent electrical transformers, backup generators, and other essential equipment to help Ukraine restore its energy grid. The European Union has also provided both financial and technical assistance, supporting Ukraine’s efforts to integrate more renewable energy into its grid and enhancing the country’s ability to import electricity from neighboring states.

6. The Role of Nuclear Energy

Ukraine’s nuclear energy plants play a critical role in the country’s electricity supply. Before the war, nuclear power accounted for around 50% of Ukraine’s total electricity generation, and for communities near the front line, electricity is civilization that depends on reliable baseload. Despite the ongoing conflict, Ukrainian nuclear plants have remained operational, though they face heightened security risks due to the proximity of active combat zones.

In the winter months, nuclear plants are expected to continue providing a significant portion of Ukraine's electricity, which is essential for meeting the country's heating and power needs. The government has made efforts to ensure the safety and security of these plants, which remain a vital part of the country's energy strategy.

Keeping the lights on in Ukraine during the winter of 2024 is no small feat, given the war-related damage to energy infrastructure, rising energy demands, and ongoing security risks. However, the Ukrainian government has taken proactive steps to address these challenges, including repairing critical infrastructure, importing energy from neighboring countries, promoting energy efficiency, and expanding renewable energy sources. International aid and the continued operation of nuclear plants also play a vital role in ensuring a reliable energy supply. While challenges remain, Ukraine’s resilience and determination to overcome its energy crisis are clear, and the country is doing everything it can to keep the lights on through this difficult winter.

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PJM and MISO Electricity-Market Reforms promise consumer savings by enabling renewables, wind, solar, and storage participation in wholesale markets, enhancing grid flexibility, reliability services, and real-time pricing across the Midwest, Great Lakes, and Mid-Atlantic.

Key Points

Market rule updates enabling renewables and storage, improving reliability and lowering consumer costs.

✅ Removes barriers to renewables, storage, demand response

✅ Improves intermarket links and real-time price signals

✅ Rewards flexible resources and reliability services

Electricity-market reforms to enable more renewables generation and storage in the Midwest, Great Lakes, and Mid-Atlantic could save consumers in the US and Canada more than $6.9 billion a year, according to a new report.

The findings may have major implications for consumer groups, large industrial companies, businesses, and homeowners in those regions, said the Wind-Solar Alliance, (WSA), which commissioned the Customer Focused and Clean report.

The WSA is a non-profit organisation supporting the growth of renewables. American Wind Energy Association CEO Tom Kiernan is listed as WSA secretary, amid ongoing debates about the US wind market today.

"Consumers are looking for clean energy, affordable and reliable energy that will keep their monthly electricity bills low," said Kristin Munsch, president of the Board of the Consumer Advocates of the PJM States, which represents over 65 million consumers in 13 states.

"There is great potential to achieve those goals with the cost-effective integration of wind, solar and battery storage plants into our wholesale power markets."

The report found the average residential customer in the PJM and Midcontinent Independent System Operator (MISO) regions, covering 29 US states and the Canadian province of Manitoba, could each save up to $48 a year as lower wholesale electricity prices materialize with significantly more wind, solar and storage on the grid.

The average annual home electricity, for example in New Jersey, in the PJM region, was just over $106 in 2018, according to the US Energy Information Administration.

The latest report quantifies the findings of a previous one for the WSA, published in November 2018, which found that outdated wholesale market rules in the US were preventing full participation by renewable energy, including wind power.

Outdated rules

"The existing wholesale power market rules were largely developed for slower-to-react conventional generators, such as coal and nuclear plants," said Michael Milligan, president of Milligan Grid Solutions and co-author of the new report.

"This report demonstrates the benefits of updating the rules to better accommodate the characteristics and potential contributions of wind and solar and other newer sources of low-cost generation."

With more renewables generation on the grid, customers would benefit the most from increasing power-system flexibility through market structures, the new report concluded. It called for the removal of artificial barriers preventing renewables, storage and demand response from participating in markets.

The report also advocated improving the connections between markets, thereby lowering transaction costs of imports and exports between neighbouring systems.

"There are currently artificial barriers that are preventing the full participation of renewables, storage and other new technologies in the PJM and MISO markets," said Michael Goggin, vice president of Grid Strategies and co-author of the report.

"Providing consumers with a real-time price signal that allows them to adjust their demand, rewarding flexible resources for their capabilities through improved market design, and allowing renewable and storage resources to participate in reliability-services markets would yield the greatest consumer benefits," he said.

PJM and MISO, which incorporate some of the windiest areas of the country, are currently reviewing their market designs as part of a broader grid overhaul underway.

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