GE Energy Wins Contracts for New Power Plants in Middle East

CO2 Tax for UK Offshore Energy Efficiency can accelerate adoption of aero-derivative gas turbines, flare gas recovery, and combined cycle power, reducing emissions on platforms like Equinor's Mariner and supporting net zero goals.

Key Points

A carbon price pushing operators to adopt efficient turbines, flare recovery, and combined cycle to cut emissions.

✅ Aero-derivative turbines beat industrial units on efficiency

✅ Flare gas recovery cuts routine flaring and fuel waste

✅ Combined cycle raises efficiency and lowers emissions

By Tom Baxter

The recent Energy Voice article from the Equinor chairman concerning the Mariner project heralding a ‘significant point of reference’ for growth highlighted the energy efficiency achievements associated with the platform.

I view energy efficiency as a key enabler to net zero, and alongside this the UK must start large-scale storage to meet system needs; it is a topic I have been involved with for many years.

As part of my energy efficiency work, I investigated Norwegian practices and compared them with the UK.

There were many differences, here are three;

1. Power for offshore installations is usually supplied from gas turbines burning fuel from the oil and gas processing plant, and even as the UK's offshore wind supply accelerates, installations convert that to electricity or couple the gas turbine to a machine such as a gas compressor.

There are two main generic types of gas turbine – aero-derivative and industrial. As the name implies aero-derivatives are aviation engines used in a static environment. Aero-derivative turbines are designed to be energy efficient as that is very import for the aviation industry.

Not so with industrial type gas turbines; they are typically 5-10% less efficient than a comparable aero-derivative.

Industrial machines do have some advantages – they can be cheaper, require less frequent maintenance, they have a wide fuel composition tolerance and they can be procured within a shorter time frame.

My comparison showed that aero-derivative machines prevailed in Norway because of the energy efficiency advantages – not the case in the UK where there are many more offshore industrial gas turbines.

Tom Baxter is visiting professor of chemical engineering at Strathclyde University and a retired technical director at Genesis Oil and Gas Consultants

2. Offshore gas flaring is probably the most obvious source of inefficient use of energy with consequent greenhouse gas emissions.

On UK installations gas is always flared due to the design of the oil and gas processing plant.

Though not a large quantity of gas, a continuous flow of gas is routinely sent to flare from some of the process plant.

In addition the flare requires pilot flames to be maintained burning at all times and, while Europe explores electricity storage in gas pipes, a purge of hydrocarbon gas is introduced into the pipes to prevent unsafe air ingress that could lead to an explosive mixture.

On many Norwegian installations the flare system is designed differently. Flare gas recovery systems are deployed which results in no flaring during continuous operations.

Flare gas recovery systems improve energy efficiency but they are costly and add additional operational complexity.

3. Returning to gas turbines, all UK offshore gas turbines are open cycle – gas is burned to produce energy and the very hot exhaust gases are vented to the atmosphere. Around 60 -70% of the energy is lost in the exhaust gases.

Some UK fields use this hot gas as a heat source for some of the oil and gas treatment operations hence improving energy efficiency.

There is another option for gas turbines that will significantly improve energy efficiency – combined cycle, and in parallel plans for nuclear power under the green industrial revolution aim to decarbonise supply.

Here the exhaust gases from an open cycle machine are taken to a separate turbine. This additional turbine utilises exhaust heat to produce steam with the steam used to drive a second turbine to generate supplementary electricity. It is the system used in most UK power stations, even as UK low-carbon generation stalled in 2019 across the grid.

Open cycle gas turbines are around 30 – 40% efficient whereas combined cycle turbines are typically 50 – 60%. Clearly deploying a combined cycle will result in a huge greenhouse gas saving.

I have worked on the development of many UK oil and gas fields and combined cycle has rarely been considered.

The reason being is that, despite the clear energy saving, they are too costly and complex to justify deploying offshore.

However that is not the case in Norway where combined cycle is used on Oseberg, Snorre and Eldfisk.

What makes the improved Norwegian energy efficiency practices different from the UK – the answer is clear; the Norwegian CO2 tax.

A tax that makes CO2 a significant part of offshore operating costs.

The consequence being that deploying energy efficient technology is much easier to justify in Norway when compared to the UK.

Do we need a CO2 tax in the UK to meet net zero – I am convinced we do. I am in good company. BP, Shell, ExxonMobil and Total are supporting a carbon tax.

Not without justification there has been much criticism of Labour’s recent oil tax plans, alongside proposals for state-owned electricity generation that aim to reshape the power market.

To my mind Labour’s laudable aims to tackle the Climate Emergency would be much better served by supporting a CO2 tax that complements the UK's coal-free energy record by strengthening renewable investment.

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Energy equity in utility regulation prioritizes fair rates, clean energy access, and DERs, addressing fixed charges and energy burdens on low-income households through stakeholder engagement and public utility commission reforms.

Key Points

Fairly allocates clean energy benefits and rate burdens, ensuring access and protections for low-income households.

✅ Reduces fixed charges that burden low-income households

✅ Funds community participation in utility proceedings

✅ Prioritizes DERs, energy efficiency, and solar in impacted areas

By Kiran Julin

Pouring over the line items on your monthly electricity bill may not sound like an enticing way to spend an afternoon, but the way electricity bills are structured has a significant impact on equitable energy access and distribution. For example, fixed fees can have a disproportionate impact on low-income households. And combined with other factors, low-income households and households of color are far more likely to report losing home heating service, with evidence from pandemic power shut-offs highlighting these disparities, according to recent federal data.

Advancing Equity in Utility Regulation, a new report published by the U.S. Department of Energy’s (DOE’s) Lawrence Berkeley National Laboratory (Berkeley Lab), makes a unifying case that utilities, regulators, and stakeholders need to prioritize energy equity in the deployment of clean energy technologies and resources, aligning with a people-and-planet electricity future envisioned by advocacy groups. Equity in this context is the fair distribution of the benefits and burdens of energy production and consumption. The report outlines systemic changes needed to advance equity in electric utility regulation by providing perspectives from four organizations — Portland General Electric, a utility company; the National Consumer Law Center, a consumer advocacy organization; and the Partnership for Southern Equity and the Center for Biological Diversity, social justice and environmental organizations.
 
“While government and ratepayer-funded energy efficiency programs have made strides towards equity by enabling low-income households to access energy-efficiency measures, that has not yet extended in a major way to other clean-energy technologies,” said Lisa Schwartz, a manager and strategic advisor at Berkeley Lab and technical editor of the report. “States and utilities can take the lead to make sure the clean-energy transition does not leave behind low-income households and communities of color. Decarbonization and energy equity goals are not mutually exclusive, and in fact, they need to go hand-in-hand.”

Energy bills and electricity rates are governed by state laws and utility regulators, whose mission is to ensure that utility services are reliable, safe, and fairly priced. Public utility commissions also are increasingly recognizing equity as an important goal, tool, and metric, and some customers face major changes to electric bills as reforms advance. While states can use existing authorities to advance equity in their decision-making, several, including Illinois, Maine, Oregon, and Washington, have enacted legislation over the last couple of years to more explicitly require utility regulators to consider equity.

“The infrastructure investments that utility companies make today, and regulator decisions about what goes into electricity bills, including new rate design steps that shape customer costs, will have significant impacts for decades to come,” Schwartz said.

Solutions recommended in the report include considering energy justice goals when determining the “public interest” in regulatory decisions, allocating funding for energy justice organizations to participate in utility proceedings, supporting utility programs that increase deployment of energy efficiency and solar for low-income households, and accounting for energy inequities and access in designing electricity rates, while examining future utility revenue models as technologies evolve.

The report is part of the Future of Electric Utility Regulation series that started in 2015, led by Berkeley Lab and funded by DOE, to encourage informed discussion and debate on utility trends and tackling the toughest issues related to state electric utility regulation. An advisory group of utilities, public utility commissioners, consumer advocates, environmental and social justice organizations, and other experts provides guidance.

Taking stock of past and current energy inequities

One focus of the report is electricity bills. In addition to charges based on usage, electricity bills usually also have a fixed basic customer charge, which is the minimum amount a household has to pay every month to access electricity. The fixed charge varies widely, from $5 to more than $20. In recent years, utility companies have sought sizable increases in this charge to cover more costs, amid rising electricity prices in some markets.

This fixed charge means that no matter what a household does to use energy more efficiently or to conserve energy, there is always a minimum cost. Moreover, low-income households often live in older, poorly insulated housing. Current levels of public and utility funding for energy-efficiency programs fall far short of the need. The combined result is that the energy burden – or percent of income needed to keep the lights on and their homes at a healthy temperature – is far greater for lower-income households.

“While all households require basic lighting, heating, cooling, and refrigeration, low-income households must devote a greater proportion of income to maintain basic service,” explained John Howat and Jenifer Bosco from the National Consumer Law Center and co-authors of Berkeley Lab’s report. Their analysis of data from the most recent U.S. Energy Information Administration’s Residential Energy Consumption Survey shows households with income less than $20,000 reported losing home heating service at a pace more than five times higher than households with income over $80,000. Households of color were far more likely than those with a white householder to report loss of heating service. In addition, low-income households and households of color are more likely to have to choose between paying their energy bill or paying for other necessities, such as healthcare or food.

Based on the most recent data (2015) from the U.S. Energy Information Administration (EIA), households with income less than $20,000 reported losing home heating service at a rate more than five times higher than households with income over $80,000. Households of color were far more likely than those with a white householder to report loss of heating service. Click on chart for larger view. (Credit: John Howat/National Consumer Law Center, using EIA data)

Moreover, while many of the infrastructure investment decisions that utilities make, such as whether and where to build a new power plant, often have long-term environmental and health consequences, impacted communities often are not at the table. “Despite bearing an inequitable proportion of the negative impacts of environmental injustices related to fossil fuel-based energy production and climate change, marginalized communities remain virtually unrepresented in the energy planning and decision-making processes that drive energy production, distribution, and regulation,” wrote Chandra Farley, CEO of ReSolve and a co-author of the report.

Engaging impacted communities
Each of the perspectives in the report identify a need for meaningful engagement of underrepresented and disadvantaged communities in energy planning and utility decision-making. “Connecting the dots between energy, racial injustice, economic disinvestment, health disparities, and other associated equity challenges becomes a clarion call for communities that are being completely left out of the clean energy economy,” wrote Farley, who previously served as the Just Energy Director at Partnership for Southern Equity. “We must prioritize the voices and lived experiences of residents if we are to have more equity in utility regulation and equitably transform the energy sector.”

In another essay in the report, Nidhi Thaker and Jake Wise from Portland General Electric identify the importance of collaborating directly with the communities they serve. In 2021, the Oregon Legislature passed Oregon HB 2475, which allows the Oregon Public Utility Commission to allocate ratepayer funding for organizations representing people most affected by a high energy burden, enabling them to participate in utility regulatory processes.

The report explains why energy equity requires correcting inequities resulting from past and present failures as well as rethinking how we achieve future energy and decarbonization goals. “Equity in energy requires adopting an expansive definition of the ‘public interest’ that encompasses energy, climate, and environmental justice. Energy equity also means prioritizing the deployment of distributed energy resources and clean energy technologies in areas that have been hit first and worst by the existing fossil fuel economy,” wrote Jean Su, energy justice director and senior attorney at the Center for Biological Diversity.

This report was supported by DOE’s Grid Modernization Laboratory Consortium, with funding from the Office of Energy Efficiency and Renewable Energy and the Office of Electricity.

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Tesla Energy Ventures Texas enters the deregulated market as a retail electricity provider, leveraging ERCOT, battery storage, solar, and grid software to enable virtual power plants and customer energy trading with Powerwall and Megapack assets.

Key Points

Tesla Energy Ventures Texas is Tesla's retail power unit selling grid and battery energy and enabling solar exports.

✅ ERCOT retail provider; sells grid and battery-stored power

✅ Uses Powerwall/Megapack; supports virtual power plants

✅ Targets Tesla owners; enables solar export and trading

Last week, Tesla Energy Ventures, a new subsidiary of electric car maker Tesla Inc. (TSLA), filed an application to become a retail electricity provider in the state of Texas. According to reports, the company plans to sell electricity drawn from the grid to customers and from its battery storage products. Its grid transaction software may also enable customers for its solar panels to sell excess electricity back to the smart grid in Texas.1

For those who have been following Tesla's fortunes in the electric car industry, the Palo Alto, California-based company's filing may seem baffling. But the move dovetails with Tesla's overall ambitions for its renewable energy business, as utilities face federal scrutiny of climate goals and electricity rates.

Why Does Tesla Want to Become an Electricity Provider?
The simple answer to that question is that Tesla already manufactures devices that produce and store power. Examples of such devices are its electric cars, which come equipped with lithium ion batteries, and its suite of battery storage products for homes and enterprises. Selling power generated from these devices to consumers or to the grid is a logical next step.

Tesla's move will benefit its operations. The filing states that it plans to build a massive battery storage plant near its manufacturing facility in Austin. The plant will provide the company with a ready and cheap source of power to make its cars.

Tesla's filing should also be analyzed in the context of the Texas grid. The state's electricity market is fully deregulated, unlike regions debating grid privatization approaches, and generated about a quarter of its overall power from wind and solar in 2020.2 The Biden administration's aggressive push toward clean energy is only expected to increase that share.

After a February fiasco in the state grid resulted in a shutdown of renewable energy sources and skyrocketing natural gas prices, Texas committed to boosting the role of battery storage in its grid. The Electricity Reliability Council of Texas (ERCOT), the state's grid operator, has said it plans to install 3,008 MW of battery storage by the end of 2022, a steep increase from the 225 MW generated at the end of 2020.3 ERCOT's proposed increase in installation represents a massive market for Tesla's battery unit.

Tesla already has considerable experience in this arena. It has built battery storage plants in California and Australia and is building a massive battery storage unit in Houston, according to a June Bloomberg report.4 The unit is expected to service wholesale power producers. Besides this, the company plans to "drum up" business among existing customers for its batteries through an app and a website that will allow them to buy and sell power among themselves, a model also being explored by Octopus Energy in international talks.

Tesla Energy Ventures: A Future Profit Center?
Tesla's foray into becoming a retail electricity provider could boost the top line for its energy services business, even as issues like power theft in India highlight retail market challenges. In its last reported quarter, the company stated that its energy generation and storage business brought in $810 million in revenues.

Analysts have forecast a positive future for its battery storage business. Alex Potter from research firm Piper Sandler wrote last year that battery storage could bring in more than $200 billion per year in revenue and grow up to a third of the company's overall business.5

Immediately after the news was released, Morningstar analyst Travis Miller wrote that Tesla does not represent an immediate threat to other major players in Texas's retail market, where providers face strict notice obligations illustrated when NT Power was penalized for delayed disconnection notices, such as NRG Energy, Inc. (NRG) and Vistra Corp. (VST). According to him, the company will initially target its own customers to "complement" its offerings in electric cars, battery, charging, and solar panels.6

Further down the line, however, Tesla's brand name and resources may work to its advantage. "Tesla's brand name recognition gives it an advantage in a hypercompetitive market," Miller wrote, adding that the car company's entry confirmed the firm's view that consumer technology or telecom companies will try to enter retail energy markets, where policy shifts like Ontario rate reductions can shape customer expectations.

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Hospital Electricity Reliability underpins ICU operations, ventilators, medical devices, and diagnostics, reducing power outages risks via grid power and backup generators, while energy poverty and blackouts magnify COVID-19 mortality in vulnerable regions.

Key Points

Hospital electricity reliability is steady power that keeps ICU care, ventilators and medical devices operating.

✅ ICU loads: ventilators, monitors, infusion pumps, diagnostics

✅ Grid power plus backup generators minimize outage risk

✅ Energy poverty increases COVID-19 mortality and infection

Robert Bryce, Contributor

During her three-year career as a registered nurse, my friend, C., has cared for tuberculosis patients as well as ones with severe respiratory problems. She’s now caring for COVID-19 patients at a hospital in Ventura County, California, where debates about keeping the lights on continue amid the state’s energy transition. Is she scared about catching the virus? “No,” she replied during a phone call on Thursday. “I’m pretty unflappable.”

What would scare her? She quickly replied, “a power outage,” a threat that grows during summer blackouts when heat waves drive demand. About a year ago, while working in Oregon, the hospital she was working in lost power for about 45 minutes. “It was terrifying,” she said. 

C., who wasn’t authorized by her hospital to talk to the media, and thus asked me to only use the initial of her first name, said that COVID-19 patients are particularly reliant on electrical devices. She quickly ticked off the machines: “The bed, the IV machine, vital signs monitor, heart monitor, the sequential compression devices...” COVID-19 patients are hooked up to a minimum of five electrical devices, she said, and if the virus-stricken patient needs high-pressure oxygen or a ventilator, the number of electrical devices could be two or three times that number. “You name it, it plugs in,” she said.  

Today In: Energy

The virus has infected some 2.2 million people around the world and killed more than 150,000,including more than 32,000 people here in the U.S. While those numbers are frightening, it is apparent that the toll would be far higher without adequate supplies of reliable electricity. Modern healthcare systems depend on electricity. Hospitals are particularly big consumers. Power demand in hospitals is about 36 watts per square meter, which is about six times higher than the electricity load in a typical American home, and utilities are turning to AI to adapt to electricity demands during surges. 

Beating the coronavirus is all about electricity. Indeed, nearly every aspect of coronavirus detection, testing, and treatment requires juice. Second, it appears that the virus is more deadly in places where electricity is scarce or unreliable. Finally, if there are power outages in virus hotspots or hospitals, a real risk in a grid with more blackouts than other developed countries, the damage will be even more severe. 

As my nurse friend in Ventura County made clear, her ability to provide high-quality care for patients is wholly dependent on reliable electricity. The thermometers used to check for fever are powered by electricity. The monitors she uses to keep track of her patients, as well as her Vocera, the walkie-talkie that she uses to communicate with her colleagues, runs on batteries. Testing for the virus requires electricity. One virus-testing machine, Abbott Labs’ m2000, is a 655-pound appliance that, according to its specification sheet, runs on either 120 or 240 volts of electricity. The operating manual for a ventilator made by Hamilton Medical is chock full of instructions relating to electricity, including how to manage the machine’s batteries and alarms. 

While it may be too soon to make a direct connection between lack of electricity and the lethality of the coronavirus, the early signs from the Navajo reservation indicate that energy poverty amplifies the danger. The sprawling reservation has about 175,000 residents, but it has a higher death toll from the virus than 13 states. About 10 percent of Navajos do not have electricity in their homes and more than 30 percent lack indoor plumbing. 

The death rate from the virus on the reservation now stands at 3.4 percent, which is nearly twice the global average. In the middle of last week, the entire population of Native American tribes in the U.S. accounted for about 1,100 confirmed cases of the virus and about 44 deaths. Navajos accounted for the majority of those, with 830 confirmed cases of coronavirus and 28 deaths. 

On Saturday night, the Navajo Times reported a major increase, with 1,197 positive cases of COVID-19 on the reservation and 44 deaths. Other factors may contribute to the high infection and mortality rates on the reservation, including  high rates of diabetes, obesity, and crowded residential living situations. That said, electricity and water are essential to good hygiene and health authorities say that frequent hand washing helps cut the risk of contracting the virus. 

The devastation happening on Navajoland provides a window into what may happen in crowded, electricity-poor countries like India, Pakistan, and Bangladesh. It also shows what could happen if a tornado or hurricane were to wipe out the electric grid in virus hotspots like New Orleans, as extreme weather increasingly afflicts the grid nationwide. Sure, most American hospitals have backup generators to help assure reliable power. But those generators can fail. Further, they usually burn diesel fuel which needs to be replenished every few days. 

The essential point here is that our hospitals and critical health care machines aren’t running on solar panels and batteries. Instead, they are running on grid power that’s being provided by reliable sources — coal, natural gas, hydro, and nuclear power — which together produce about 89 percent of the electricity consumed in this country, even as Russian hacking of utilities highlights cyber risks. The pandemic — which is inflicting trillions of dollars of damage on our economy and tens of thousands of deaths — underscores the criticality of abundant and reliable electricity to our society and the tremendous damage that would occur if our health care infrastructure were to be hit by extended blackouts during the fight to stop COVID-19.

In a follow-up interview on Saturday with my friend, C., she told me that while caring for patients, she and her colleagues “are entirely dependent on electricity. We take it for granted. It’s a hidden assumption in our work,” a reminder echoed by a grid report card that warns of dangerous vulnerabilities. She quickly added she and her fellow nurses “aren’t trained or equipped to deal with circumstances that would come with shoddy power. If we lost power completely, people will die.”

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Dubai Green Hydrogen advances electrolysis at the Mohammed Bin Rashid Al Maktoum Solar Park, with DEWA and Siemens enabling clean energy storage, re-electrification, and fuel-cell mobility for Expo 2020 Dubai and public transport.

Key Points

Dubai Green Hydrogen is a DEWA-Siemens project making solar hydrogen for storage, mobility, and reelectrification.

✅ Electrolysis at Mohammed Bin Rashid Al Maktoum Solar Park

✅ Partners: DEWA and Siemens; public-private demonstration plant

✅ Hydrogen for buses, re-electrification, and energy storage

Something you hear frequently if you are a clean tech aficionado is that excess solar and wind power can be used to split water into oxygen and hydrogen. The Dubai Supreme Council of Energy, the 2020 Dubai Higher Committee and the Dubai Electricity and Water Authority broke ground in early February on a solar power hydrogen electrolysis facility located in the Mohammed Bin Rashid Al Maktoum Solar Park, and related initiatives like the Solar Decathlon Middle East underscore Dubai's clean energy focus. Sheikh Ahmed bin Saeed Al Maktoum, chairman of the Dubai Supreme Council of Energy and chairman of the Expo 2020 Dubai Higher Committee, participated in the groundbreaking ceremony, according to a report by Khaleej Times.

Saeed Mohammed Al Tayer, CEO of DEWA, said at the groundbreaking ceremony the project is important to understanding the limits of green hydrogen technology and how it can contribute to the UAE’s vision of clean energy, and aligns with DEWA's latest renewable initiatives now progressing in the emirate. “This pioneering project is a role model for strategic partnerships between the public and private sectors. It will contribute to developing the green economy concept in the UAE and explore the potential of green hydrogen technology. The hydrogen produced at the facility will be stored and deployed for re-electrification, transportation and other uses.”

Siemens is providing much of the technology that will be used at the demonstration facility, while DEWA expands its China outreach to woo renewable energy firms that can contribute to the ecosystem. Joe Kaeser, president and CEO of Siemens, said the UAE was the perfect location for Siemens to test the technology, building on advances in offshore green hydrogen the company is pursuing. One of the primary uses of the hydrogen produced will be to power Dubai’s public transportation system.

“We are aware of the stress that is placed on vehicles in this region due to the high levels of heat; with hydrogen cells, you are not putting as much strain on the vehicle and that improves its longevity,” Kaeser said. “However, this is only the first step and we are eager to explore more ways in which we can adapt the technology to other sectors. The interest from various companies and partners has been immense and we are eager to work with all interested parties.”

“Dewa, Expo 2020 Dubai and Siemens are working together to help realize His Highness Sheikh Mohammed bin Rashid Al Maktoum, Vice-President and Prime Minister of the UAE and Ruler of Dubai’s, vision to identify new energy resources and provide sustainable power as part of a balanced approach that prioritizes the environment. Our aim is to make Dubai a model of energy efficiency and safety,” said Sheikh Ahmed.

Expo 2020 Dubai intends to use the hydrogen generated at the facility to transport visitors to the Expo 2020 Dubai and the Mohammed bin Rashid Al Maktoum Solar Park, reflecting regional momentum such as Saudi Arabia's clean energy plans over the next decade, in hydrogen fuel cell powered vehicles. Live data of the green hydrogen electrolysis will be displayed at Expo 2020 Dubai to help inform broader efforts like hydrogen hubs in the United States.

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Electric Field-Induced Glass Softening reveals a Joule heating anomaly in silicate glass, where anode-side nanoscale alkali depletion drives ionic conduction, localized thermal runaway, melting, and evaporation, challenging homogeneity assumptions and refining materials processing models.

Key Points

An effect where electric fields lower glass softening temperature via nanoscale ionic migration and structural change.

✅ Anode-side alkali depletion creates extreme, localized heating

✅ Thermal runaway melts glass near the anode despite uniform bulk

✅ Findings refine Joule heating models and enable new glass processing

A team of scientists working with electrical currents and silicate glass have been left gobsmacked after the glass appeared to defy a basic physical law, in a field that also explores electricity-from-air devices for novel energy harvesting.

If you pass an electrical current through a material, the way that current generates heat can be described by Joule's first law. It's been observed time and time again, with the temperature always evenly distributed when the material is homogeneous (or uniform).

But not in this recent experiment. A section - and only a section - of silicate glass became so hot that it melted, and even evaporated. Moreover, it did so at a much lower temperature than the boiling point of the material.

The boiling point of pure silicate glass is 2,230 degrees Celsius (4,046 degrees Fahrenheit). The hottest temperature the researchers recorded in a homogeneous piece of silicate glass during the experiment was 1,868.7 degrees Celsius.

Say whaaaat.

"The calculations did not add up to explain what we were seeing as simply standard Joule heating," said engineer and materials scientist Himanshu Jain of Lehigh University.

"Even under very moderate conditions, we observed fumes of glass that would require thousands of degrees higher temperature than Joule's law could predict!"

Jain and his colleagues from materials science company Corning Incorporated were investigating a phenomenon they had described in a previous paper. In 2015, they reported that an electric field could reduce the temperature at which glass softens, by as much as a few hundred degrees, a line of inquiry that parallels work on low-cost heat-to-electricity materials in energy research. They called this "electric field-induced softening."

It was certainly a peculiar phenomenon, so they set up another experiment. They put pieces of glass in a furnace, and applied 100 to 200 volts in the form of both alternating and direct currents.

Next, a thin wisp of vapour emanated from the spot where the anode conveying the current contacted the glass.

"In our experiments, the glass became more than a thousand degrees Celsius hotter near the positive side than in the rest of the glass, which was very surprising considering that the glass was totally homogeneous to begin with," Jain said.

This seems to fly in the face of Joule's first law, so the team investigated more closely - and found that the glass wasn't remaining as homogeneous as it started out. The electric field changed the chemistry and the structure of the glass on nanoscale, in just a small section close to the anode.

This region heats faster than the rest of the glass, to the point of becoming a thermal runaway - where an increase in temperature further increases temperature in a blistering feedback loop.

As it turned out, that spot of structural change and dramatic heat resulted in a small area of glass reaching melting point while the rest of the material remained solid.

"Unlike electronically conducting metals and semiconductors, with time the heating of ionically conducting glass becomes extremely inhomogeneous with the formation of a nanoscale alkali-depletion region, such that the glass melts near the anode, even evaporates, while remaining solid elsewhere," the researchers wrote in their paper.

In other words, the material wasn't homogeneous any more, which means the glass heating experiment doesn't exactly change how we apply Joule's first law.

But it's an exciting result, since until now we didn't know a material could actually lose its homogeneity with the application of an electrical current, with possible implications for thin-film heat harvesters in electronics. (The thing is, no one had tried electrically heating glass to these extreme temperatures before.)

So the physical laws of the Universe are still okay, as a piece of glass hasn't broken them. But Joule's first law may need a bit of tweaking to take this effect into account, a reminder that unconventional energy concepts like nighttime solar cells also challenge our intuitions.

And, of course, it's another piece of understanding that could help us in other ways too, including advances in thermoelectric materials that turn waste heat into electricity.

"Besides demonstrating the need to qualify Joule's law," Jain said, "the results are critical to developing new technology for the fabrication and manufacturing of glass and ceramic materials."

The research has been published in Scientific Reports.

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