Universal Powerline Association (UPA) and OPERA Announce Joint Agreement on Powerline Access Specification

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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US Electricity Generation H1 2018 saw wind and solar gains but hydro declines, as natural gas led the grid mix and coal fell; renewables' share, GWh, emissions, and capacity additions shaped the power sector.

Key Points

It is the H1 2018 US power mix, where natural gas led, coal declined, and wind and solar grew while hydro fell.

✅ Natural gas reached 32% of generation, highest share

✅ Coal fell; renewables roughly tied nuclear at ~20%

✅ Wind and solar up; hydro output down vs 2017

To complement our revival of US electricity capacity reports, here’s a revival of our reports on US electricity generation.

As with the fresh new capacity report, things are not looking too bright when it comes to electricity generation. There’s still a lot of grey — in the bar charts below, in the skies near fossil fuel power plants, and in the human and planetary outlook based on how slowly we are cutting fossil fuel electricity generation.

As you can see in the charts above, wind and solar energy generation increased notably from the first half of 2017 to the first half of 2018, and the EIA expected larger summer solar and wind generation in subsequent months, reinforcing that momentum.

A large positive when it comes to the environment and human health is that coal generation dropped a great deal year over year — by even more than renewables increased, though the EIA later noted an increase in coal-fired generation in a subsequent year, complicating the trend. However, on the down side, natural gas soared as it became the #1 source of electricity generation in the United States (32% of US electricity). Furthermore, coal was still solidly in the #2 position (27% of US electricity). Renewables and nuclear were essentially in a tie at 19.8% of generation, with renewables just a tad above nuclear.

Actually, combined with an increase in nuclear power generation, natural gas electricity production increased so much that the renewable energy share of electricity generation actually dropped in the first half of 2018 versus the first half of 2017, even amid declining electricity use in some periods. It was 19.8% this year and 20% last year.

Again, solar and wind saw a significant growth in its market share, from 9% to 9.9%, but hydro brought the whole category down due to a decrease from 9% to 8%.

The visuals above are probably the best way to examine it all. The H1 2018 chart was still dominated by fossil fuels, which together accounted for approximately 60% of electricity generation, even though by 2021 non-fossil sources supplied about 40% of U.S. electricity, highlighting the longer-term shift. In H1 2017, the figure was 59.7%. Furthermore, if you switch to the “Change H1 2018 vs H1 2017 (GWh)” chart, you can watch a giant grey bar representing natural gas take over the top of the chart. It almost looks like it’s part of the border of the chart. The biggest glimmer of positivity in that chart is seeing the decline in coal at the bottom.

What will the second half of the year bring? Well, the gigantic US electricity generation market shifts slowly, even as monthly figures can swing, as January generation jumped 9.3% year over year according to the EIA, reminding us about volatility. There is so much base capacity, and power plants last so long, that it takes a special kind of magic to create a rapid transition to renewable energy. As you know from reading this quarter’s US renewable energy capacity report, only 43% of new US power capacity in the first half of the year was from renewables. The majority of it was from natural gas. Along with other portions of the calculation, that means that electricity generation from natural gas is likely to increase more than electricity generation from renewables.

Jump into the numbers below and let us know if you have any more thoughts.

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Vehicle-to-Grid (V2G) enables EV batteries to provide grid balancing, flexibility, and demand response, integrating renewables with bidirectional charging, reducing peaker plant reliance, and unlocking distributed energy storage from millions of connected electric vehicles.

Key Points

Vehicle-to-Grid (V2G) lets EVs export power via bidirectional charging to balance grids and support renewables.

✅ Turns parked EVs into distributed energy storage assets

✅ Delivers balancing services and demand response to the grid

✅ Cuts peaker plant use and supports renewable integration

“There are already many Gigawatt-hours of batteries on wheels”, which could be used to provide balance and flexibility to electrical grids, if the “ultimate potential” of vehicle-to-grid (V2G) technology could be harnessed.

That’s according to a panel of experts and stakeholders convened by our sister site Current±, which covers the business models and technologies inherent to the low carbon transition to decentralised and clean energy. Focusing mainly on the UK grid but opening up the conversation to other territories and the technologies themselves, representatives including distribution network operator (DNO) Northern Powergrid’s policy and markets director and Nissan Europe’s director of energy services debated the challenges, benefits and that aforementioned ultimate potential.

Decarbonisation of energy systems and of transport go hand-in-hand amid grid challenges from rising EV uptake, with vehicle fuel currently responsible for more emissions than electricity used for energy elsewhere, as Ian Cameron, head of innovation at DNO UK Power Networks says in the Q&A article.

“Furthermore, V2G technology will further help decarbonisation by replacing polluting power plants that back up the electrical grid,” Marc Trahand from EV software company Nuvve Corporation added, pointing to California grid stability initiatives as a leading example.

While the panel states that there will still be a place for standalone utility-scale energy storage systems, various speakers highlighted that there are over 20GWh of so-called ‘batteries on wheels’ in the US, capable of powering buildings as needed, and up to 10 million EVs forecast for Britain’s roads by 2030.

“…it therefore doesn’t make sense to keep building expensive standalone battery farms when you have all this capacity on wheels that just needs to be plugged into bidirectional chargers,” Trahand said.

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Duke Energy Smart Meters enable remote meter reading, daily energy usage data, and two-way outage detection via AMI, with encrypted data, faster restoration, and remote connect/disconnect for Indiana customers in Howard County.

Key Points

Advanced meters that support remote readings, daily usage insights, two-way outage detection, and secure, encrypted data.

✅ Daily energy usage available online the next day

✅ Two-way communications speed outage detection and restoration

✅ Remote connect/disconnect; manual reads optional with opt-out fee

Say goodbye to your neighborhood meter reader. Say hello to your new smart meter.

Over the next three months, Duke Energy will install nearly 43,000 new high-tech electric meters for Howard County customers that will allow the utility company to remotely access meters via the digital grid instead of sending out employees to a homeowner's property for walk-by readings.

That means there's no need to estimate bills when meters can't be easily accessed, such as during severe weather or winter storms.

Other counties serviced by Duke Energy slated to receive the meters include Miami, Tipton, Cass and Carroll counties.

Angeline Protogere, Duke Energy's lead communication consultant, said besides saving the company money and manpower, the new smart meters come with a host of benefits for customers enabled by smart grid solutions today.

The meters are capable of capturing daily energy usage data, which is available online the next day. Having this information available on a daily basis can help customers make smarter energy decisions and support customer analytics that avoid billing surprises at the end of the month, she said.

"The real advantage is for the consumer, because they can track their energy usage and adjust their usage before the bills come," Protogere said.

When it comes to power outages, the meters are capable of two-way communications. That allows the company to know more about an outage through synchrophasor monitoring, which can help speed up restoration. However, customers will still need to notify Duke Energy if their power goes out.

If a customer is moving, they don't have to wait for a Duke Energy representative to come to the premises to connect or disconnect the energy service because requests can be performed remotely.

Protogere said when it comes to installing the meters, the changeover takes less than 5 minutes to complete. Customers should receive advance notices from the company, but the technician also will knock on the door to let the customer know they are there.

If no one is available and the meter is safely accessible, the technician will go ahead and change out the meter, Protogere said. There will be a momentary outage between the time the old meter is removed and the new meter is installed.

Kokomo and the surrounding areas are one of the last parts of the state to receive Duke Energy's new, high-tech meters, which are commonly used by other utility companies and in smart city initiatives across the U.S.

Protogere said statewide, the company started installing smart meters in August 2016 as utilities deploy digital transformer stations to modernize the grid. To date, they have installed 694,000 of the 854,000 they have planned for the state.

The company says the information stored and transmitted on the smart meters is safe, protected and confidential. Duke Energy said on its website that it does not share data with anyone without customers' authorization. The information coming from the meters is encrypted and protected from the moment it is collected until the moment it is purged, the company said.

Digital smart meter technology uses radio frequency bands that have been used for many years in devices such as baby monitors and medical monitors. The radio signals are far below the levels emitted by common household appliances and electronics, including cellphones and microwave ovens.

According to the World Health Organization, FCC, U.S. Food and Drug Administration and Electric Power Research Institute, no adverse health effects have been shown to occur from the radio frequency signals produced by smart meters or other such wireless networks.

However, customers can still opt-out of getting a smart meter and continue to have their meter manually read.

Those who choose not to get a smart meter must pay a $75 initial opt-out fee and an additional $17.50 monthly meter reading charge per account.

If smart meters have not yet been installed, Duke Energy will waive the $75 initial opt-out fee if customers notify the company they want to opt out within 21 days of receiving the installation postcard notice.

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EV Decarbonization Strategy weighs life-cycle emissions and climate targets, highlighting mode shift to public transit, cycling, and walking, grid decarbonization, renewable energy, and charging infrastructure to cut greenhouse gases while reducing private car dependence.

Key Points

A plan to cut transport emissions by pairing EV adoption with mode shift, clean power, and less private car use.

✅ Prioritize mode shift: transit, cycling, and walking.

✅ Electrify remaining vehicles with clean, renewable power.

✅ Expand charging, improve batteries, and manage critical minerals.

California recently announced that it plans to ban the sales of gas-powered vehicles by 2035, a move similar to a 2035 electric vehicle mandate seen elsewhere, Ontario has invested $500 million in the production of electric vehicles (EVs) and Tesla is quickly becoming the world's highest-valued car company.

It almost seems like owning an electric vehicle is a silver bullet in the fight against climate change, but it isn't, as a U of T study explains today. What we should also be focused on is whether anyone should use a private vehicle at all.
 
As a researcher in sustainable mobility, I know this answer is unsatisfying. But this is where my latest research has led.

Battery EVs, such as the Tesla Model 3 - the best selling EV in Canada in 2020 - have no tailpipe emissions. But they do have higher production and manufacturing emissions than conventional vehicles, and often run on electricity that comes from fossil fuels.

Almost 18 per cent of the electricity generated in Canada came from fossil fuels in 2019, and even as Canada's EV goals grow more ambitious today, the grid mix varies from zero in Quebec to 90 per cent in Alberta.
 
Researchers like me compare the greenhouse gas emissions of an alternative vehicle, such as an EV, with those of a conventional vehicle over a vehicle lifetime, an exercise known as a life-cycle assessment. For example, a Tesla Model 3 compared with a Toyota Corolla can provide up to 75 per cent reduction in greenhouse gases emitted per kilometre travelled in Quebec, but no reductions in Alberta.

Hundreds of millions of new cars

To avoid extreme and irreversible impacts on ecosystems, communities and the overall global economy, we must keep the increase in global average temperatures to less than 2 C - and ideally 1.5 C - above pre-industrial levels by the year 2100.

We can translate these climate change targets into actionable plans. First, we estimate greenhouse gas emissions budgets using energy and climate models for each sector of the economy and for each country. Then we simulate future emissions, taking alternative technologies into account, as well as future potential economic and societal developments.

I looked at the U.S. passenger vehicle fleet, which adds up to about 260 million vehicles, while noting the potential for Canada-U.S. collaboration in this transition, to answer a simple question: Could the greenhouse gas emissions from the sector be brought in line with climate targets by replacing gasoline-powered vehicles with EVs?

The results were shocking. Assuming no changes to travel behaviours and a decarbonization of 80 per cent of electricity, meeting a 2 C target could require up to 300 million EVs, or 90 per cent of the projected U.S. fleet, by 2050. That would require all new purchased vehicles to be electric from 2035 onwards.

To put that into perspective, there are currently 880,000 EVs in the U.S., or 0.3 per cent of the fleet. Even the most optimistic projections, despite hype about an electric-car revolution gaining steam, from the International Energy Agency suggest that the U.S. fleet will only be at about 50 per cent electrified by 2050.

Massive and rapid electrification

Still, 90 per cent is theoretically possible, isn't it? Probably, but is it desirable?

In order to hit that target, we'd need to very rapidly overcome all the challenges associated with EV adoption, such as range anxiety, the higher purchase cost and availability of charging infrastructure.
 
A rapid pace of electrification would severely challenge the electricity infrastructure and the supply chain of many critical materials for the batteries, such as lithium, manganese and cobalt. It would require vast capacity of renewable energy sources and transmission lines, widespread charging infrastructure, a co-ordination between two historically distinct sectors (electricity and transportation systems) and rapid innovations in electric battery technologies. I am not saying it's impossible, but I believe it's unlikely.

Read more: There aren't enough batteries to electrify all cars - focus on trucks and buses instead

So what? Shall we give up, accept our collective fate and stop our efforts at electrification?

On the contrary, I think we should re-examine our priorities and dare to ask an even more critical question: Do we need that many vehicles on the road?

Buses, trains and bikes

Simply put, there are three ways to reduce greenhouse gas emissions from passenger transport: avoid the need to travel, shift the transportation modes or improve the technologies. EVs only tackle one side of the problem, the technological one.

And while EVs do decrease emissions compared with conventional vehicles, we should be comparing them to buses, including leading electric bus fleets in North America, trains and bikes. When we do, their potential to reduce greenhouse gas emissions disappears because of their life cycle emissions and the limited number of people they carry at one time.

If we truly want to solve our climate problems, we need to deploy EVs along with other measures, such as public transit and active mobility. This fact is critical, especially given the recent decreases in public transit ridership in the U.S., mostly due to increasing vehicle ownership, low gasoline prices and the advent of ride-hailing (Uber, Lyft)

Governments need to massively invest in public transit, cycling and walking infrastructure to make them larger, safer and more reliable, rather than expanding EV subsidies alone. And we need to reassess our transportation needs and priorities.

The road to decarbonization is long and winding. But if we are willing to get out of our cars and take a shortcut through the forest, we might get there a lot faster.

Author: Alexandre Milovanoff - Postdoctoral Researcher, Environmental Engineering, University of Toronto 

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Rooftop Solar Battery Backup helps Californians keep lights on during PG&E blackouts, combining home energy storage with grid-tied systems for wildfire prevention, outage resilience, and backup power when solar panels cannot supply nighttime demand.

Key Points

A home battery paired with rooftop solar, providing backup power and blackout resilience when the grid is down.

✅ Works when grid is down; panels alone stop for safety.

✅ Requires home battery storage; market adoption is growing.

✅ Supports wildfire mitigation and PG&E outage preparedness.

Californians have embraced rooftop solar panels more than anyone in the U.S., but amid California's solar boom many are learning the hard way the systems won’t keep the lights on during blackouts.

That’s because most panels are designed to supply power to the grid -- not directly to houses, though emerging peer-to-peer energy models may change how neighbors share power in coming years. During the heat of the day, solar systems can crank out more juice than a home can handle, a challenge also seen in excess solar risks in Australia today. Conversely, they don’t produce power at all at night. So systems are tied into the grid, and the vast majority aren’t working this week as PG&E Corp. cuts power to much of Northern California to prevent wildfires, even as wildfire smoke can dampen solar output during such events.

The only way for most solar panels to work during a blackout is pairing them with solar batteries that store excess energy. That market is just starting to take off. Sunrun Inc., the largest U.S. rooftop solar company, said some of its customers are making it through the blackouts with batteries, but it’s a tiny group -- countable in the hundreds.

“It’s the perfect combination for getting through these shutdowns,” Sunrun Chairman Ed Fenster said in an interview. He expects battery sales to boom in the wake of the outages, as the state has at times reached a near-100% renewables mark that heightens the need for storage.

And no, trying to run appliances off the power in a Tesla Inc. electric car won’t work, at least without special equipment, and widespread U.S. power-outage risks are a reminder to plan for home backup.

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