Nuclear has a place in Ontario energy mix

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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Rooftop solar grids transform urban infrastructure with distributed generation, photovoltaic panels, smart grid integration and energy storage, cutting greenhouse gas emissions, lowering utility costs, enabling net metering and community solar for low-carbon energy systems.

Key Points

Rooftop solar grids are PV systems on buildings that generate power, cut emissions, and enable smart grid integration.

✅ Lowers utility bills via net metering and demand offset

✅ Reduces greenhouse gases and urban air pollution

✅ Enables resiliency with storage, smart inverters, and microgrids

As urban areas expand and the climate crisis intensifies, cities are seeking innovative ways to integrate renewable energy sources into their infrastructure. One such solution gaining traction is the installation of rooftop solar grids. A recent CBC News article highlights the significant impact of these solar systems on urban environments, showcasing their benefits and the challenges they present.

Harnessing Unused Space for Sustainable Energy

Rooftop solar panels are revolutionizing how cities approach energy consumption and environmental sustainability. By utilizing the often-overlooked space on rooftops, these systems provide a practical solution for generating renewable energy in densely populated areas. The CBC article emphasizes that this approach not only makes efficient use of available space but also contributes to reducing a city's reliance on non-renewable energy sources.

The ability to generate clean energy directly from buildings helps decrease greenhouse gas emissions and, as scientists work to improve solar and wind power, promotes a shift towards a more sustainable energy model. Solar panels absorb sunlight and convert it into electricity, reducing the need for fossil fuels and lowering overall carbon footprints. This transition is crucial as cities grapple with rising temperatures and air pollution.

Economic and Environmental Advantages

The economic benefits of rooftop solar grids are considerable. For homeowners and businesses, installing solar panels can lead to substantial savings on electricity bills. The initial investment in solar technology is often balanced by long-term energy savings and financial incentives, such as tax credits or rebates, and evidence that solar is cheaper than grid electricity in Chinese cities further illustrates the trend toward affordability. According to the CBC report, these financial benefits make solar energy a compelling option for many urban residents and enterprises.

Environmentally, the advantages are equally compelling. Solar energy is a renewable and clean resource, and increasing the number of rooftop solar installations can play a pivotal role in meeting local and national renewable energy targets, as illustrated when New York met its solar goals early in a recent milestone. The reduction in greenhouse gas emissions from fossil fuel energy sources directly contributes to mitigating climate change and improving air quality.

Challenges in Widespread Adoption

Despite the clear benefits, the adoption of rooftop solar grids is not without its challenges. One of the primary hurdles is the upfront cost of installation. While prices for solar panels have decreased over time, the initial financial outlay remains a barrier for some property owners, and regions like Alberta have faced solar expansion challenges that highlight these constraints. Additionally, the effectiveness of solar panels can vary based on factors such as geographic location, roof orientation, and local weather patterns.

The CBC article also highlights the importance of supportive infrastructure and policies for the success of rooftop solar grids. Cities need to invest in modernizing their energy grids to accommodate the influx of solar-generated electricity, and, in the U.S., record clean energy purchases by Southeast cities have signaled growing institutional demand. Furthermore, policies and regulations must support solar adoption, including issues related to net metering, which allows solar panel owners to sell excess energy back to the grid.

Innovative Solutions and Future Prospects

The future of rooftop solar grids looks promising, thanks to ongoing technological advancements. Innovations in photovoltaic cells and energy storage solutions are expected to enhance the efficiency and affordability of solar systems. The development of smart grid technology and advanced energy management systems, including peer-to-peer energy sharing, will also play a critical role in integrating solar power into urban infrastructures.

The CBC report also mentions the rise of community solar projects as a significant development. These projects allow multiple households or businesses to share a single solar installation, making solar energy more accessible to those who may not have suitable rooftops for solar panels. This model expands the reach of solar technology and fosters greater community engagement in renewable energy initiatives.

Conclusion

Rooftop solar grids are emerging as a key element in the transition to sustainable urban energy systems. By leveraging unused rooftop space, cities can harness clean, renewable energy, reduce greenhouse gas emissions, and, as developers learn that more energy sources make better projects, achieve long-term economic savings. While there are challenges to overcome, such as initial costs and regulatory hurdles, the benefits of rooftop solar grids make them a crucial component of the future energy landscape. As technology advances and policies evolve, rooftop solar grids will play an increasingly vital role in shaping greener, more resilient urban environments.

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EU Electricity Market Reform advances two-way CfDs, PPAs, and fixed-price tariffs to cut volatility, support renewables and nuclear, stabilize investor revenues, and protect consumers from price spikes across wholesale power markets.

Key Points

An EU plan expanding two-way CfDs, PPAs, and fixed-price contracts to curb price swings and support low-carbon power.

✅ Two-way CfDs return excess revenues to consumers

✅ Boosts PPAs and fixed-price retail options

✅ Targets renewables, nuclear; limits fossil exposure

The European Union wants to expand the use of contracts that pay power plants a fixed price for electricity, a draft proposal showed, as part of an electricity market revamp to shield European consumers from big price swings.

The European Commission pledged last year to reform the EU's electricity market rules, after record-high gas prices, caused by cuts to Russian flows, sent power prices soaring, prompting debates over gas price cap strategies in response.

A draft of the EU executive's proposal, seen by Reuters on Tuesday and due to be published on Mar. 16, steered clear of the deep redesign of the electricity market that some member states have called for, even as nine EU countries opposed sweeping reforms as a fix earlier in the crisis, suggesting instead limited changes to nudge countries towards more predictable, fixed-price power contracts.

If EU countries want to support new investments in wind, solar, geothermal, hydropower and nuclear electricity, for example - a point over which France and Germany have wrestled - they should use a two-way contract for difference (CfD) or an equivalent contract, the draft said.

The aim is to provide a stable revenue stream to investors, and help make consumers' energy bills less volatile, even though rolling back electricity prices is tougher than it appears. Restricting this support to renewable and low-carbon electricity also aims to speed up Europe's shift away from fossil fuels.

Two-way CfDs offer generators a fixed "strike price" for their electricity, regardless of the price in short-term energy markets. If the market price is above the CfD strike price, then the extra revenue the generator receives should be handed out to final electricity consumers, the draft EU document said.

Countries should also make it easier for power buyers to sign power purchase agreements (PPA) - another type of long-term contract to directly buy electricity from a generator.

Governments should also make sure consumers have access to fixed-price electricity contracts - echoing France's new electricity pricing scheme to reassure Brussels - giving them the option to avoid a contract that would expose them to volatile prices swings in energy markets, the draft said.

If European energy prices were to spike to extreme levels again, the Commission suggested allowing national governments to temporarily intervene to fix prices while weighing emergency measures to limit prices where needed, and offer consumers and small businesses a share of their electricity at a lower price.

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Texas PUC Spanish Power to Choose mandates bilingual parity in deregulated electricity markets, ensuring equal access to plans, transparent pricing, consumer protection, and provider listings for Spanish speakers, mirroring the English site offerings statewide.

Key Points

PUC mandate requiring identical Spanish and English plan listings for fair access in the deregulated power market.

✅ Orders parity across English and Spanish plan listings

✅ Increases transparency in a deregulated electricity market

✅ Deadline set for providers to post on both sites

The state’s Public Utility Commission has ordered that the Spanish-language version of the Power to Choose website provide the same options available on the English version of the site, a move that comes as shopping for electricity is getting cheaper statewide.

Texas is one of a handful of states with a deregulated electricity market, with ongoing market reforms under consideration to avoid blackouts. The idea is to give consumers the option to pick power plans that they think best fit their needs. Customers can find available plans on the state’s Power To Choose website, or its Spanish-language counterpart, Poder de Escoger. In theory, those two sites should have the exact same offerings, so no one is disadvantaged. But the Texas Public Utility Commission found that wasn’t the case.

Houston Chronicle business reporter Lynn Sixel has been covering this story. She says the Power to Choose website is important for consumers facing the difficult task of choosing an electric provider in a deregulated state, where electricity complaints have recently reached a three-year high for Texans.

“There are about 57 providers listed on the [English] Power to Choose website, and news about retailers like Griddy underscores how varied the offerings can be across providers. [Last week] there were only 23 plans on the Spanish Power to Choose site,” Sixel says. “If you speak Spanish and you’re looking for a low-cost plan, as of last week, it would have been difficult to find some of the really great offers.”

Mustafa Tameez, managing director of Outreach Strategists, a Houston firm that consults with companies and nonprofits on diversity, described this issue as a type of redlining.

“He’s referring to a practice that banks would use to circle areas on maps in which the bank decided they did not want to lend money or would charge higher rates,” Sixel says. “Typically it was poor minority neighborhoods. Those folks would not get the same great deals that their Anglo neighbors would get.”

DeAnn Walker, chairman of the Public Utility Commission, said she was not at all happy about the plans listings in a meeting Friday, against a backdrop where Texas utilities have recently backed out of a plan to create smart home electricity networks.

“She gave a deadline of 8 a.m. Monday morning for any providers who wanted to put their plans on the Power to Choose website, must put them on both the Spanish language and the English language versions,” Sixel says. “All the folks that I talked to really had no idea that there were different plans on both sites and I think that there was sort of an assumption.”

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AP1000 Refueling Outage Record showcases Westinghouse nuclear power excellence as Sanmen Unit 2 completes its first reactor refueling in 28.14 days, highlighting safety, reliability, outage optimization, and economic efficiency in China.

Key Points

It is the 28.14-day initial refueling at Sanmen Unit 2, a global benchmark achieved with Westinghouse AP1000 technology.

✅ 28.14-day first refueling at Sanmen Unit 2 sets global benchmark

✅ AP1000 design simplifies systems, improves safety and reliability

✅ Outage optimization by Westinghouse and CNNC accelerates schedules

Westinghouse Electric Company China operations today announced that Sanmen Unit 2, one of the world's first AP1000® nuclear power plants, has set a new refueling outage record in the global nuclear power industry, completing its initial outage in 28.14 days.

"Our innovative AP1000 technology allows for simplified systems and significantly reduces the amount of equipment, while improving the safety, reliability and economic efficiency of this nuclear power plant, reflecting global nuclear milestones reached recently," said Gavin Liu, president of the Westinghouse Asia Operating Plant Services Business. "We are delighted to see the first refueling outage for Sanmen Unit 2 was completed in less than 30 days. This is a great achievement for Sanmen Nuclear Power Company and further demonstrates the outstanding performance of AP1000 design."

All four units of the AP1000 nuclear power plants in China have completed their first refueling outages in the past 18 months, aligning with China's nuclear energy development momentum across the sector.  The duration of each subsequent outage has fallen significantly - from 46.66 days on the first outage to 28.14 days on Sanmen Unit 2.

"During the first AP1000 refueling outage at the Sanmen site in December 2019, a Westinghouse team of experts worked side-by-side with the Sanmen outage team to partner on outage optimization, and immediately set a new standard for a first-of-a-kind outage, while major refurbishments like the Bruce refurbishment moved forward elsewhere," said Miao Yamin, chairman of CNNC Sanmen Nuclear Power Company Limited. "Lessons learned were openly exchanged between our teams on each subsequent outage, which has built to this impressive achievement."

Westinghouse provided urgent technical support on critical issues during the outage, as international programs such as Barakah Unit 1 achieved key milestones, to help ensure that work was carried out on schedule with no impact to critical path.

In addition to the four AP1000 units in China, two units are under construction at the Vogtle expansion near Waynesboro, Georgia, USA.

Separately, in the United States, a new reactor startup underscored renewed momentum in nuclear generation this year.

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BC Hydro Trades Electrical Safety addresses electric contact incidents among trade workers, emphasizing power line hazards, overhead lines clearance, the 3 m rule, jobsite planning, and safety training to prevent injuries during spring and summer.

Key Points

BC Hydro Trades Electrical Safety is guidance and training to reduce power-line contact risks for trade workers.

✅ Stay at least 3 m from overhead power lines and equipment

✅ Plan worksites and spot hazards before starting tasks

✅ Use BC Hydro electrical awareness training near electricity

A BC Hydro report finds serious electrical contact incidents are more common among trades workers, and research shows this is partly due to a knowledge gap in the electricity sector in Canada.

Trade workers were involved in more than 60 per cent of electric contact incidents that led to serious injuries over the last three years, according to BC Hydro.

One-in-five trade workers have also either made contact or had a close call with electric equipment.

A recent worksite electrocution case underscores the consequences of contact.

“New research finds many have had a close call with electricity on the job or have witnessed unsafe work near overhead lines or electrical equipment,” BC Hydro staff said in the report.

“A gap in electrical safety knowledge is a contributing factor in most of these incidents.”

Most electrical contact incidents take place in the spring and summer, when trade workers are working outdoors and are working in close proximity to power lines.

BC Hydro offered tips for trades workers who may work closely to possible electrical contact points:

• Look up and down – Observe the site beforehand and plan work so you can avoid contact with power lines
• Stay back – You and your tools should stay at least 3 m away from an overhead power line
• Call for help – If you come across a fallen power line, or a tree branch or object contacts a line—stay back 10 metres and call 911. Never try and move it yourself. If you must work closer than 3 m to a power line at your worksite, call BC Hydro before you begin.
• Learn about the risks – BC Hydro offers in-person and online electrical awareness training, such as arc flash training, for anyone who works near electricity.

The report found that 38 per cent of trades workers who participated in the report said they only feel “somewhat informed” about safety measures around working near electricity and 71 per cent were unable to identify the correct distance they should be away from active power lines or electrical equipment.

BC Hydro said trade workers should participate in its electrical awareness training courses, including arc flash training, to make sure all safety measures are taken.

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