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Infrastructure Security Algorithm prioritizes cyber defense for power grids and critical infrastructure, mitigating ransomware, blackout risks, and cascading failures by guiding utilities, regulators, and cyber insurers on optimal security investment allocation.

Key Points

An algorithm that optimizes security spending to cut ransomware and blackout risks across critical infrastructure.

✅ Guides utilities on optimal security allocation

✅ Uses incentives to correct human risk biases

✅ Prioritizes assets to prevent cascading outages

Millions of people could suddenly lose electricity if a ransomware attack just slightly tweaked energy flow onto the U.S. power grid, as past US utility intrusions have shown.

No single power utility company has enough resources to protect the entire grid, but maybe all 3,000 of the grid's utilities could fill in the most crucial security gaps if there were a map showing where to prioritize their security investments.

Purdue University researchers have developed an algorithm to create that map. Using this tool, regulatory authorities or cyber insurance companies could establish a framework for protecting the U.S. power grid that guides the security investments of power utility companies to parts of the grid at greatest risk of causing a blackout if hacked.

Power grids are a type of critical infrastructure, which is any network - whether physical like water systems or virtual like health care record keeping - considered essential to a country's function and safety. The biggest ransomware attacks in history have happened in the past year, affecting most sectors of critical infrastructure in the U.S. such as grain distribution systems in the food and agriculture sector and the Colonial Pipeline, which carries fuel throughout the East Coast, prompting increased military preparation for grid hacks in the U.S.

With this trend in mind, Purdue researchers evaluated the algorithm in the context of various types of critical infrastructure in addition to the power sector, including electricity-sector IoT devices that interface with grid operations. The goal is that the algorithm would help secure any large and complex infrastructure system against cyberattacks.

"Multiple companies own different parts of infrastructure. When ransomware hits, it affects lots of different pieces of technology owned by different providers, so that's what makes ransomware a problem at the state, national and even global level," said Saurabh Bagchi, a professor in the Elmore Family School of Electrical and Computer Engineering and Center for Education and Research in Information Assurance and Security at Purdue. "When you are investing security money on large-scale infrastructures, bad investment decisions can mean your power grid goes out, or your telecommunications network goes out for a few days."

Protecting infrastructure from hacks by improving security investment decisions

The researchers tested the algorithm in simulations of previously reported hacks to four infrastructure systems: a smart grid, industrial control system, e-commerce platform and web-based telecommunications network. They found that use of this algorithm results in the most optimal allocation of security investments for reducing the impact of a cyberattack.

The team's findings appear in a paper presented at this year's IEEE Symposium on Security and Privacy, the premier conference in the area of computer security. The team comprises Purdue professors Shreyas Sundaram and Timothy Cason and former PhD students Mustafa Abdallah and Daniel Woods.

"No one has an infinite security budget. You must decide how much to invest in each of your assets so that you gain a bump in the security of the overall system," Bagchi said.

The power grid, for example, is so interconnected that the security decisions of one power utility company can greatly impact the operations of other electrical plants. If the computers controlling one area's generators don't have adequate security protection, as seen when Russian hackers accessed control rooms at U.S. utilities, then a hack to those computers would disrupt energy flow to another area's generators, forcing them to shut down.

Since not all of the grid's utilities have the same security budget, it can be hard to ensure that critical points of entry to the grid's controls get the most investment in security protection.

The algorithm that Purdue researchers developed would incentivize each security decision maker to allocate security investments in a way that limits the cumulative damage a ransomware attack could cause. An attack on a single generator, for instance, would have less impact than an attack on the controls for a network of generators, which sophisticated grid-disruption malware can target at scale, rather than for the protection of a single generator.

Building an algorithm that considers the effects of human behavior

Bagchi's research shows how to increase cybersecurity in ways that address the interconnected nature of critical infrastructure but don't require an overhaul of the entire infrastructure system to be implemented.

As director of Purdue's Center for Resilient Infrastructures, Systems, and Processes, Bagchi has worked with the U.S. Department of Defense, Northrop Grumman Corp., Intel Corp., Adobe Inc., Google LLC and IBM Corp. on adopting solutions from his research. Bagchi's work has revealed the advantages of establishing an automatic response to attacks, and analyses like Symantec's Dragonfly report highlight energy-sector risks, leading to key innovations against ransomware threats, such as more effective ways to make decisions about backing up data.

There's a compelling reason why incentivizing good security decisions would work, Bagchi said. He and his team designed the algorithm based on findings from the field of behavioral economics, which studies how people make decisions with money.

"Before our work, not much computer security research had been done on how behaviors and biases affect the best defense mechanisms in a system. That's partly because humans are terrible at evaluating risk and an algorithm doesn't have any human biases," Bagchi said. "But for any system of reasonable complexity, decisions about security investments are almost always made with humans in the loop. For our algorithm, we explicitly consider the fact that different participants in an infrastructure system have different biases."

To develop the algorithm, Bagchi's team started by playing a game. They ran a series of experiments analyzing how groups of students chose to protect fake assets with fake investments. As in past studies in behavioral economics, they found that most study participants guessed poorly which assets were the most valuable and should be protected from security attacks. Most study participants also tended to spread out their investments instead of allocating them to one asset even when they were told which asset is the most vulnerable to an attack.

Using these findings, the researchers designed an algorithm that could work two ways: Either security decision makers pay a tax or fine when they make decisions that are less than optimal for the overall security of the system, or security decision makers receive a payment for investing in the most optimal manner.

"Right now, fines are levied as a reactive measure if there is a security incident. Fines or taxes don't have any relationship to the security investments or data of the different operators in critical infrastructure," Bagchi said.

In the researchers' simulations of real-world infrastructure systems, the algorithm successfully minimized the likelihood of losing assets to an attack that would decrease the overall security of the infrastructure system.

Bagchi's research group is working to make the algorithm more scalable and able to adapt to an attacker who may make multiple attempts to hack into a system. The researchers' work on the algorithm is funded by the National Science Foundation, the Wabash Heartland Innovation Network and the Army Research Lab.

Cybersecurity is an area of focus through Purdue's Next Moves, a set of initiatives that works to address some of the greatest technology challenges facing the U.S. Purdue's cybersecurity experts offer insights and assistance to improve the protection of power plants, electrical grids and other critical infrastructure.

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Airport City Solar Edmonton will deliver a 120-megawatt, 627-acre photovoltaic, utility-scale renewable energy project at EIA, creating jobs, attracting foreign investment, and supplying clean power to Fortis Alberta and airport distribution systems.

Key Points

A 120 MW, 627-acre photovoltaic solar farm at EIA supplying clean power to Fortis Alberta and airport systems.

✅ 120 MW utility-scale project over 627 acres at EIA

✅ Feeds Fortis Alberta and airport distribution networks

✅ Drives jobs, investment, and regional sustainability

A European-based company is proposing to build a solar farm bigger than 300 CFL football fields at Edmonton's international airport, aligning with Alberta's red-hot solar growth seen across the province.

Edmonton International Airport and Alpin Sun are working on an agreement that will see the company develop Airport City Solar, a 627-acre, 120-megawatt solar farm that reflects how renewable power developers combine resources for stronger projects on what is now a canola field on the west side of the airport lands.

The solar farm will be the largest at an airport anywhere in the world, EIA said in a news release Tuesday, in a region that also hosts the largest rooftop solar array at a local producer.

"It's a great opportunity to drive economic development as well as be better for the environment," Myron Keehn, vice-president, commercial development and air service at EIA, told CBC News, even as Alberta faces challenges with solar expansion that require careful planning.

"We're really excited that [Alpin Sun] has chosen Edmonton and the airport to do it. It's a great location. We've got lots of land, we're geographically located north, which is great for us, because it allows us to have great hours of sunlight.

"As everyone knows in Edmonton, you can golf early in the morning or golf late at night in the summertime here. And in wintertime it's great, because of the snow, and the reflective [sunlight] off the snow that creates power as well."

Airport official Myron Keehn says the field behind him will become home to the world's largest solar farm at an airport. (Scott Neufeld/CBC)

The project will "create jobs, provide sustainable solar power for our region and show our dedication to sustainability," Tom Ruth, EIA president and CEO, said in the news release, while complementing initiatives by Ermineskin First Nation to expand Indigenous participation in electricity generation.

Construction is expected to begin in early 2022, as new solar facilities in Alberta demonstrate lower costs than natural gas. The solar farm would be operational by the end of that year, the release said. 

Alpin Sun says the project will bring in $169 million in foreign investment to the Edmonton metro region amid federal green electricity contracts that are boosting market certainty. 

Power generated by Airport City Solar will feed into Fortis Alberta and airport distribution systems.

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US Termination of Ukraine Energy Grid Support signals a policy shift: USAID halts aid for grid restoration amid Russia attacks, impacting energy security, infrastructure resilience, winter readiness, and negotiations leverage with Moscow and allies.

Key Points

A US policy reversal ending USAID support for Ukraine's grid, impacting energy security, resilience, and leverage.

✅ USAID halt reduces funds for grid restoration and winter prep

✅ Policy shift may weaken Kyiv's leverage in talks with Russia

✅ Ukraine seeks EU, IFIs, private capital for energy resilience

The U.S. government has recently decided to terminate its support for Ukraine's energy grid restoration, a critical initiative managed by the U.S. Agency for International Development (USAID). This decision, reported by NBC News, comes at a time when Ukraine is grappling with significant challenges to its energy infrastructure due to ongoing Russian attacks. The termination of support was reportedly finalized before Ukrainian President Volodymyr Zelensky's scheduled visit to Washington, marking a significant shift in U.S. policy and raising concerns about the broader implications for Ukraine's energy resilience and its negotiations with Russia.

The Critical Role of U.S. Support

Since Russia's invasion of Ukraine, the country’s energy infrastructure has been one of the primary targets of military strikes. Russia has launched numerous attacks on Ukraine's power generation facilities, substations, and power lines, causing power outages across multiple regions. These attacks have led to significant material losses, with damage reaching billions of dollars. As part of its commitment to Ukraine, the U.S. government, through USAID, had been instrumental in funding restoration efforts aimed at rebuilding and reinforcing Ukraine’s energy grid.

USAID's support was crucial in helping Ukraine withstand the damage inflicted by Russian missile strikes. This aid was not just about restoring basic services but also about fortifying the energy grid to ensure that Ukraine could continue functioning amidst the war and keep the lights on this winter as temperatures drop. The U.S. contribution to Ukraine's energy sector, alongside international support, helped reduce the immediate vulnerabilities faced by Ukraine's civilians and industries.

The Abrupt Change in U.S. Policy

The decision to cut support for energy grid restoration is seen as a sharp reversal in U.S. policy, particularly as the Biden administration has previously shown strong backing for Ukraine in the aftermath of the invasion. This shift in policy was reportedly made by the U.S. State Department, which directed USAID to halt its involvement in the energy sector.

According to NBC News, USAID officials expressed concern about the timing of this decision. One official noted that terminating support for Ukraine’s energy grid restoration would severely undermine the U.S. government's ability to negotiate on issues like ceasefires and peace talks with Russia. The official argued that such a move would signal to Russia that the U.S. is backing away from its long-term investments in Ukraine, potentially weakening Ukraine's position in the ongoing war.

The abrupt end to this support is also seen as a blow to the morale of Ukraine’s government and people. Ukraine had been heavily reliant on the U.S. for resources to repair its critical infrastructure, and the decision to cut this support without warning has created uncertainty about the future of such recovery efforts.

Ukraine’s Response and Search for Alternatives

In response to the termination of U.S. support, Ukrainian officials have been seeking alternative sources of funding to continue the restoration of their energy grid. Deputy Prime Minister Olha Stefanishyna reported that Ukraine has already reached preliminary agreements with other international partners to secure financial support for energy resilience, cyber defense, and recovery programs including new energy solutions for winter blackouts.

These efforts come at a time when Ukraine is working to rebuild its war-torn economy and safeguard critical sectors like energy and infrastructure. The termination of U.S. support for energy restoration projects underscores the growing pressure on Ukraine to diversify its sources of aid and not become overly dependent on any one nation. Ukrainian leaders are in ongoing talks with European governments, international financial institutions, and private investors to ensure that essential programs do not stall due to the lack of funding from the U.S., as energy cooperation grows and Ukraine helps Spain amid blackouts in solidarity.

Implications for Ukraine’s Energy Security

Ukraine's energy security remains a critical issue in the context of the ongoing conflict with Russia. The war has made the country’s energy infrastructure vulnerable to repeated attacks, and the restoration of this infrastructure is essential for ensuring that Ukraine can keep the lights on and recover in the long term. The U.S. has been one of the largest contributors to Ukraine's energy security efforts, and its withdrawal could force Ukraine to look for other partners who may not have the same level of financial or technological resources.

This development also raises questions about the future of U.S. involvement in Ukraine's recovery efforts more broadly. As the war continues and winter looms over the battlefront for frontline communities, the need for reliable and sustained support from international partners will only increase. If the U.S. significantly scales back its aid, Ukraine may face even greater challenges in maintaining its energy infrastructure and achieving long-term recovery.

Moving Forward

The termination of U.S. support for Ukraine’s energy grid restoration serves as a reminder of the complexities involved in international aid and geopolitics during wartime. As Ukraine faces the ongoing realities of the war, it must adapt to a shifting international landscape where traditional allies may not always be reliable sources of support. Ukraine’s leadership will need to be strategic in its search for alternative sources of aid, while also focusing on strengthening its energy grid, managing electricity reserves to stabilize supply, and reducing its vulnerabilities to Russian attacks.

While the end of U.S. support for Ukraine's energy restoration is a significant setback, it also underscores the urgent need for Ukraine to diversify its international partnerships. The future of Ukraine’s energy resilience may depend on how effectively it can navigate these changing dynamics while maintaining the support of the international community in the fight against Russian aggression.

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Nunavut electricity rate increase sees QEC raise domestic electricity rates 6.6% over two years, affecting customer rates, base rates, subsidies, and kWh overage charges across communities, with public housing exempt and territory-wide pricing denied.

Key Points

A 6.6% QEC hike over 2018-2019, affecting customer rates, subsidies, and kWh overage; public housing remains exempt.

✅ 3.3% on May 1, 2018; 3.3% on Apr 1, 2019

✅ Subsidy caps: 1,000 kWh Oct-Mar; 700 kWh Apr-Sep

✅ Territory-wide base rate denied; public housing exempt

Ahead of the Nunavut government's approval of the general rate increase for the Qulliq Energy Corporation, many Nunavummiut wondered how the change would impact their electricity bills.

QEC's request for a 6.6-per-cent increase was approved by the government last week. The increase will be spread out over two years, a pattern similar to BC Hydro's two-year rate plan, with the first increase (3.3 per cent) effective May 1, 2018. The remaining 3.3 per cent will be applied on April 1, 2019.

Public housing units, however, are exempt from the government's increase altogether.

The power corporation also asked for a territory-wide rate, so every community would pay the same base rate (we'll go over specific terms in a minute if you're not familiar with them). But that request was denied, even as Manitoba Hydro scaled back increases next year, and QEC will now take the next two years reassessing each community's base rate.

#google#

So, what does this mean for your home's power bill? Well, there's a few things you need to know, which we'll get to in a second.

But in essence, as long as you don't go over the government-subsidized monthly electricity usage limit, you're paying an extra 3.61 cents per kilowatt hour (kWh).

To be clear, we're talking about non-government domestic rates — basically, private homeowners — and those living in a government-owned unit but pay for their own power.

The basics

First, some quick terminology. The "base rate" term we're going to use (and used above) in this story refers to the community rate. As in, what QEC charges customers in every community. The "customer rate" is the rate customers actually pay, after the government's subsidy.

The first thing you need to know is everyone in Nunavut starts off by paying the same customer rate, unlike jurisdictions using a price cap to limit spikes.

That's because the government subsidizes electricity costs, and that subsidy is different in every community, because the base rate is different.

For example, Iqaluit's new base rate after the 3.3 per cent increase (remember, the 6.6 per cent is being applied over two years) is 56.69 cents per kWh, while Kugaaruk's base rate rose to 112.34 cents per kWh. Those, by the way, are the territory's lowest and highest respective base rates.

However, customers in both Iqaluit and Kugaaruk will each now pay 28.35 cents per kWh because, remember, the government subsidizes the base rates in every community.

Now, remember earlier we mentioned a "government-subsidized monthly electricity usage limit?" That's where customers in various communities start to pay different amounts.

As simply as we can explain it, the government will only cover so much electricity usage in a month, in every household.

Between October and March, the government will subsidize the first 1,000 kilowatt hours, and only 700 kilowatt hours from April to September. QEC says the average Nunavut home will use about 500 kilowatt hours every month over the course of a year.

But if your household goes over that limit, you're at the mercy of your community's base rate for any extra electricity you use. Homes in Kugaaruk in December, for instance, will have to pay that 122.34 cents for every extra kilowatt hour it uses, while homes in Iqaluit only have to pay 56.69 cents per kWh for its extra electricity.

That's where many Nunavummiut have criticized the current rate structure, because smaller communities are paying more for their extra costs than larger communities.

QEC had hoped — as it had asked for — to change the structure so every community pays the same base rate. So regardless of if people go over their electricity usage limits for the government subsidy, everyone would pay the same overage rates.

But the government denied that request.

New rate is actually lower

The one thing we should highlight, however, is the new rate after the increase is actually lower than what customers were paying in 2014.

For the past seven months, customers have been getting power from QEC at a discount, whereas Newfoundland customers began paying for Muskrat Falls during the same period, to different effect.

That's because when QEC sets its rates, it does so based on global oil price forecasts. Since 2014, the price of oil worldwide has slumped, and so QEC was able to purchase it at less than it had anticipated.

When that happens, and QEC makes more than $1 million within a six month period thanks to the lower oil prices, it refunds the excess profits back to customers through a discount on electricity base rates — a mechanism similar to a lump-sum credit used elsewhere — the government subsidy, however, doesn't change so the savings are passed on directly to customers.

Now, the 6.6 per cent increase to electricity rates, is actually being applied to the discounted base rate from the last seven months.

So again, while customers are paying more than they have been for the last seven months, it's lower than what they were paying in 2014.

Lastly, to be clear, all the figures used in this story are only for domestic non-government rates. Commercial rates and changes have not been explored in this story, given the differences in subsidy and rate application.

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Gander Curling Club Debt Forgiveness Agreement explained: town council tax relief, loan write-off conditions, community benefits, and economic impact, covering long-standing taxes and loans while protecting the facility with asset clauses and compliance terms.

Key Points

Town plan erasing 25 years of tax and loan debt, with conditions to keep the curling facility open for residents.

✅ Conditions: no borrowing against property without consent.

✅ Water and sewer taxes must be paid annually.

✅ If sold or use changes, debt due; transfer for $1.

Gander town council has agreed to forgive the local curling club's debt of over $250,000.

Gina Brown, chair of the town council's finance committee, says the agreement has been put in place to help the curling club survive, amid broader discussions on electricity affordability in Newfoundland and Labrador.

"When we took a look at this and realized there was a significant outstanding debt for Gander curling club … we have to mitigate," Brown told CBC Newfoundland Morning. "[Getting] what the taxpayers are owed, with also understanding and appreciating the role that that recreational facility plays in our community."

According to Brown, the debt comes from a combination of taxes and loans, going back about 25 years. She says the curling club understood there was debt, but didn't know the number was so high. The club has been in the black since 2007, but used their profits for other items like renovations.

"Like so many cases when you're dealing with an organization with a changing board, and the same for council … [people are] coming in and coming out," Brown said. "And as a result, my understanding from the curling club's perspective is they weren't aware of how much was outstanding."

Chris McLeod, president of the Gander Curling Club, told CBC the club had been trying to address the debt since he became president in 2014.

Terms of agreement
The town's agreement with the club comes with the following stipulations:

The club will not use the property as security for any form of borrowing without the town's consent.
 
The club will continue to pay water and sewer tax annually.
 
If the club sells the property, the town reserves the right to void the agreement and the debt will immediately become due in full.
 
If the club stops using the facility as a curling club, the property will be transferred to the town for $1.
McLeod says the club will not attempt to pay back the debt, as it is not part of the agreement. The only way the debt would be paid is if the building is sold, which McLeod says it won't be, and there are also no plans to use the building for anything other than a curling club.

"[The debt] is basically gone now," McLeod said.

McLeod says the move was made to help get the debt off the books, and make sure the curling club can be financially responsible in the future, similar to relief programs some utilities offered during the pandemic.

The curling club is something that encourages people. So we felt that this has to be maintained.
- Gina Brown

Brown says keeping the curling club in Gander is important for the town, and brings different benefits to the area, as regional power cooperation debates illustrate broader trends.

"They are servicing people from as young as Grade 1 to seniors," Brown said. "You need little to no equipment, you need no background. So for the town itself, for its social and health implications, as provinces advance emissions plans that can affect communities, is one. But the other thing is the economic benefit that comes from having this facility here."

The Gander Curling Club's debt forgiveness comes with several conditions. (Google Maps)
The curling club can help attract people into the community, as recreational facilities are often a key draw for families, she added, while other provinces are creating transition funds to support communities.

"When you're as a town, trying to attract people coming in … whether you're a doctor, nurse, anybody looking at the recreational facilities, the curling club is something that encourages people," Brown said. "So we felt that this has to be maintained."

Brown says the town understands they might be setting a precedent with other businesses in forgiving the debts of the curling club, as major infrastructure like B.C.'s Site C dam has faced budget overruns.

"That's another thing we had to consider, what kind of precedents are [we] establishing?" Brown said. "From our standpoint, I think one of the things about this agreement that we felt was beneficial to the town is that they have an asset, helping to avoid costly delays seen with large projects. And the asset is a great building. To us, the taxpayers are in a win-win situation."

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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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