A greener way to get power from natural gas

Polycrystalline Tin Selenide Thermoelectrics enable waste heat recovery with ZT 3.1, matching single crystals while cutting costs, powering greener car engines, industrial furnaces, and thermoelectric generators via p-type and emerging n-type designs.

Key Points

Low-cost tin selenide devices that turn waste heat into power, achieving ZT 3.1 and enabling p-type and n-type modules.

✅ Oxygen removal prevents heat-leaking tin oxide grain skins.

✅ Polycrystalline ingots match single-crystal ZT 3.1 at lower cost.

✅ N-type tin selenide in development to pair with p-type.

So-called thermoelectric generators turn waste heat into electricity without producing greenhouse gas emissions, providing what seems like a free lunch. But despite helping power the Mars rovers, the high cost of these devices has prevented their widespread use. Now, researchers have found a way to make cheap thermoelectrics that work just as well as the pricey kind. The work could pave the way for a new generation of greener car engines, industrial furnaces, and other energy-generating devices.

“This looks like a very smart way to realize high performance,” says Li-Dong Zhao, a materials scientist at Beihang University who was not involved with the work. He notes there are still a few more steps to take before these materials can become high-performing thermoelectric generators. However, he says, “I think this will be used in the not too far future.”

Thermoelectrics are semiconductor devices placed on a hot surface, like a gas-powered car engine or on heat-generating electronics using thin-film converters to capture waste heat. That gives them a hot side and a cool side, away from the hot surface. They work by using the heat to push electrical charges from one to the other, a process of turning thermal energy into electricity that depends on the temperature gradient. If a device allows the hot side to warm up the cool side, the electricity stops flowing. A device’s success at preventing this, as well as its ability to conduct electrons, feeds into a score known as the figure of merit, or ZT.

 Over the past 2 decades, researchers have produced thermoelectric materials with increasing ZTs, while related advances such as nighttime solar cells have broadened thermal-to-electric concepts. The record came in 2014 when Mercouri Kanatzidis, a materials scientist at Northwestern University, and his colleagues came up with a single crystal of tin selenide with a ZT of 3.1. Yet the material was difficult to make and too fragile to work with. “For practical applications, it’s a non-starter,” Kanatzidis says.

So, his team decided to make its thermoelectrics from readily available tin and selenium powders, an approach that, once processed, makes grains of polycrystalline tin selenide instead of the single crystals. The polycrystalline grains are cheap and can be heated and compressed into ingots that are 3 to 5 centimeters long, which can be made into devices. The polycrystalline ingots are also more robust, and Kanatzidis expected the boundaries between the individual grains to slow the passage of heat. But when his team tested the polycrystalline materials, the thermal conductivity shot up, dropping their ZT scores as low as 1.2.

In 2016, the Northwestern team discovered the source of the problem: an ultrathin skin of tin oxide was forming around individual grains of polycrystalline tin selenide before they were pressed into ingots. And that skin acted as an express lane for the heat to travel from grain to grain through the material. So, in their current study, Kanatzidis and his colleagues came up with a way to use heat to drive any oxygen away from the powdery precursors, leaving pristine polycrystalline tin selenide, whereas other devices can generate electricity from thin air using ambient moisture.

The result, which they report today in Nature Materials, was not only a thermal conductivity below that of single-crystal tin selenide but also a ZT of 3.1, a development that echoes nighttime renewable devices showing electricity from cold conditions. “This opens the door for new devices to be built from polycrystalline tin selenide pellets and their applications to be explored,” Kanatzidis says.

Getting through that door will still take some time. The polycrystalline tin selenide the team makes is spiked with sodium atoms, creating what is known as a “p-type” material that conducts positive charges. To make working devices, researchers also need an “n-type” version to conduct negative charges.

Zhao’s team recently reported making an n-type single-crystal tin selenide by spiking it with bromine atoms. And Kanatzidis says his team is now working on making an n-type polycrystalline version. Once n-type and p-type tin selenide devices are paired, researchers should have a clear path to making a new generation of ultra-efficient thermoelectric generators. Those could be installed everywhere from automobile exhaust pipes to water heaters and industrial furnaces to scavenge energy from some of the 65% of fossil fuel energy that winds up as waste heat. 

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EU Winter Energy Mix 2022-2023 shows renewables, wind, solar, and hydro overtaking coal and gas, as demand fell amid high prices; Ember and IEA confirm lower emissions across Europe during the energy crisis.

Key Points

It describes Europe's winter power mix: reduced coal and gas, and record wind, solar, and hydro output.

✅ Coal generation fell 11% YoY; gas output declined even more.

✅ Renewables supplied 40%: wind, solar, and hydro outpaced fossil fuels.

✅ Ember and IEA confirm trends; mild winter tempered demand.

The EU burned less coal this winter during the energy crisis than in previous years, according to an analysis, quashing fears that consumption of the most polluting fossil fuel would soar as countries scrambled to find substitutes for lost supplies of Russian gas.

The study from energy think-tank Ember shows that between October 2022 and March 2023 coal generation fell 27 terawatt hours, or almost 11 per cent year on year, while gas generation fell 38 terawatt hours, as renewables crowded out gas and consumers cut electricity consumption in response to soaring prices.

Renewable energy supplies also rose, with combined wind and solar power and hydroelectric output outstripping fossil fuel generation for the first time, providing 40 per cent of all electricity supplies. The Financial Times checked Ember’s findings with the International Energy Agency, which said they broadly matched its own preliminary analysis of Europe’s electricity generation over the winter.

The study demonstrates that fears of a steep rebound in coal usage in Europe’s power mix were overstated, despite the continent’s worst energy crisis in 40 years following Russia’s full-scale invasion of Ukraine, even as stunted hydro and nuclear output in parts of Europe posed challenges.

While Russia slashed gas supplies to Europe and succeeded in boosting energy prices for consumers to record levels, the push by governments to rejuvenate old coal plants, including Germany's coal generation, to ensure the lights stayed on ultimately did not lead to increased consumption.

“With Europe successfully on the other side of this winter and major supply disruptions avoided, it is clear the threatened coal comeback did not materialise,” analysts at Ember said in the report.

“With fossil fuel generation down, EU power sector emissions during winter were the lowest they have ever been.”

Ember cautioned, however, that Europe had been assisted by a mild winter that helped cut electricity demand for heating and there was no guarantee of such weather next winter. Companies and households had also endured a lot of pain as a result of the higher prices that had led them to cut consumption, even though in some periods, such as the latest lockdown, power demand held firm in parts of Europe.

Total electricity consumption between October and March declined 94 terawatt hours, or 7 per cent, compared with the same period in winter 2021/22, continuing post-Covid transition dynamics across Europe.

“For a lot of people this winter was really hard with electricity prices that were extraordinarily high and we shouldn’t lose sight of that,” said Ember analyst Harriet Fox.

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ACCC energy underwriting guarantee proposes government-backed certainty for new generation, cutting electricity prices and supporting gas, pumped hydro, renewables, batteries, and potentially coal-fired power, addressing market failure without direct subsidies.

Key Points

A tech-neutral, government-backed plan underwriting new generation revenue to increase certainty and cut power prices.

✅ Government guarantee provides a revenue floor for new generators.

✅ Technology neutral: coal, gas, renewables, pumped hydro, batteries.

✅ Intended to reduce bills by up to $400 and address market failure.

Australian Taxpayers won't directly fund any new power plants despite some Coalition MPs seizing on a new report to call for a coal-fired power station.

The Australian Competition and Consumer Commission recommended the government give financial certainty to new power plants, guaranteeing energy will be bought at a cheap price if it can't be sold, as part of an electricity market plan to avoid threats to supply.

It's part of a bid to cut up to $400 a year from average household power prices.

Prime Minister Malcolm Turnbull said the finance proposal had merit, but he ruled out directly funding specific types of power generation.

"We are not in the business of subsidising one technology or another," he told reporters in Queensland today.

"We've done enough of that. Frankly, there's been too much of that."

Renewable subsidies, designed in the 1990s to make solar and wind technology more affordable, have worked and will end in 2020.

Some Coalition MPs claim the ACCC's recommendation to underwrite power generation is vindication for their push to build new coal-fired power plants.

But ACCC chair Rod Sims said no companies had proposed building new coal plants - instead they're trying to build new gas projects, pumped hydro or renewable projects.

Opposition Leader Bill Shorten said Mr Turnbull was offering solutions years away, having overseen a rise in power prices over the past year.

"You don't just go down to K-Mart and get a coal-fired power station off the shelf," Mr Shorten told reporters, admitting he had not read the ACCC report.

Energy Minister Josh Frydenberg said the recommendation to underwrite new power generators had a lot of merit, as it would address a market failure highlighted by AEMO warnings about reduced reserves.

"What they're saying is the government needs to step in here to provide some sort of assurance," Mr Frydenberg told 9NEWS today.

He said that could include coal, gas, renewable energy or battery storage.

Deputy Nationals leader Bridget McKenzie said science should determine which technology would get the best outcomes for power bills, with a scrapping coal report suggesting it can be costly.

Mr Turnbull said there was strong support for the vast majority of the ACCC's 56 recommendations, but the government would carefully consider the report, which sets out a blueprint to cut electricity bills by 25 percent.

Acting Greens leader Adam Bandt said Australia should exit coal-fired power in favour of renewable energy to cut pollution.

In contrast, Canada has seen the Stop the Shock campaign advocate a return to coal power in some provinces.

The Australian Energy Council, which represents 21 major energy companies, said the government should consult on changes to avoid "unintended consequences".

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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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Denmark Renewable Energy Outlook assesses Eurostat ranking, district heating and trash incineration, EV adoption, wind turbine testing expansions, and electrification to cut CO2, aligning policies with EU 2050 climate goals and green electricity usage.

Key Points

A brief analysis of Denmark's green power use, electrification, EVs, and policies needed to meet EU 2050 CO2 goals.

✅ Eurostat rank low due to trash incineration in district heating.

✅ EV adoption stalled after tax reinstatement, slowing electrification.

✅ Wind test centers expanded; electrification could cut 95% CO2.

Denmark’s low ranking in the latest figures from Eurostat regarding climate-friendly electricity, which places the country in 32nd place out of 40 countries, is partly a result of the country’s reliance on the incineration of trash to warm our homes via long-established district heating systems.

Additionally, there are not enough electric vehicles – a recent increase in sales was halted in 2016 when the government started to phase back registration taxes scrapped in 2008, and Europe’s EV slump underscores how fragile momentum can be.

Not enough green electricity being used

Denmark is good at producing green electricity, reports Politiken, but it does not use enough, and amid electricity price volatility in Europe this is bad news if it wants to fulfil the EU’s 2050 goal to eliminate CO2 emissions.

A recent report by Eurelectric and McKinsey demonstrates that if heating, transport and industry were electrified, reflecting a broader European push for electrification across the energy system, 95 percent of the country’s CO2 emissions could be eliminated by that date.

Wind turbine testing centre expansion approved

Parliament has approved the expansion of two wind turbine centres in northwest Jutland, supporting integration as e-mobility drives electricity demand in the coming years. The centres in Østerild and Høvsøre will have the capacity to test nine and seven turbines, measuring 330 and 200 metres in size (up from 250 and 165) respectively. The Østerild expansion should be completed in 2019, while Høvsøre ​​will have to wait a little longer.

Third on the Environmental Performance Index

Denmark finished third on the latest Environmental Performance Index, finishing only behind Switzerland and France. Its best category ranking was third for Environmental Health, and comparative energy efficiency benchmarking can help contextualize progress. Elsewhere, it ranked 11th for Ecosystem Vitality, 18th for Biodiversity and Habitat, 94th for Forests, 87th for Fisheries, 25th for Climate and Energy and 37th for Air Pollution, 14th for Water Resources and 7th for Agriculture.

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Offshore Wind-to-Hydrogen Integration enables green hydrogen by embedding an electrolyzer in offshore turbines. Siemens Gamesa and Siemens Energy align under H2Mare to decarbonize industry, advance the Paris Agreement, and unlock scalable, off-grid renewable production.

Key Points

A method integrating electrolyzers into offshore wind turbines to generate green hydrogen and reduce carbon emissions.

✅ Integrated electrolyzer at turbine base for off-grid operation

✅ Enables scalable, cost-efficient green hydrogen production

✅ Supports decarbonization targets under Paris Agreement

To reach the Paris Agreement goals, the world will need vast amounts of green hydrogen and, with offshore wind growth accelerating, wind will provide a large portion of the power needed for its production.

Siemens Gamesa and Siemens Energy announced today that they are joining forces combining their ongoing wind-to-hydrogen developments to address one of the major challenges of our decade - decarbonizing the economy to solve the climate crisis.

The companies are contributing with their developments to an innovative solution that fully integrates an electrolyzer into an offshore wind turbine as a single synchronized system to directly produce green hydrogen. The companies intend to provide a full-scale offshore demonstration of the solution by 2025/2026. The German Federal Ministry of Education and Research, reflecting Germany's clean energy progress, announced today that the developments can be implemented as part of the ideas competition 'Hydrogen Republic of Germany'.

'Our more than 30 years of experience and leadership in the offshore wind industry, coupled with Siemens Energy's expertise in electrolyzers, brings together brilliant minds and cutting-edge technologies to address the climate crisis. Our wind turbines play a huge role in the decarbonization of the global energy system, and the potential of wind to hydrogen means that we can do this for hard-to-abate industries too. It makes me very proud that our people are a part of shaping a greener future,' said Andreas Nauen, Siemens Gamesa CEO.

Christian Bruch, CEO of Siemens Energy, explains: 'Together with Siemens Gamesa, we are in a unique position to develop this game changing solution. We are the company that can leverage its highly flexible electrolyzer technology and create and redefine the future of sustainable offshore energy production. With these developments, the potential of regions with abundant offshore wind, such as the UK offshore wind sector, will become accessible for the hydrogen economy. It is a prime example of enabling us to store and transport wind energy, thus reducing the carbon footprint of economy.'

Over a time frame of five years, Siemens Gamesa plans to invest EUR 80 million and Siemens Energy is targeting to invest EUR 40 million in the developments. Siemens Gamesa will adapt its development of the world's most powerful turbine, the SG 14-222 DD offshore wind turbine to integrate an electrolysis system seamlessly into the turbine's operations. By leveraging Siemens Gamesa's intricate knowledge and decades of experience with offshore wind, electric losses are reduced to a minimum, while a modular approach ensures a reliable and efficient operational set-up for a scalable offshore wind-to-hydrogen solution. Siemens Energy will develop a new electrolysis product to not only meet the needs of the harsh maritime offshore environment and be in perfect sync with the wind turbine, but also to create a new competitive benchmark for green hydrogen.

The ultimate fully integrated offshore wind-to-hydrogen solution will produce green hydrogen using an electrolyzer array located at the base of the offshore wind turbine tower, blazing a trail towards offshore hydrogen production. The solution will lower the cost of hydrogen by being able to run off grid, much like solar-powered hydrogen in Dubai showcases for desert environments, opening up more and better wind sites. The companies' developments will serve as a test bed for making large-scale, cost-efficient hydrogen production a reality and will prove the feasibility of reliable, effective implementation of wind turbines in systems for producing hydrogen from renewable energy.

The developments are part of the H2Mare initiative which is a lighthouse project likely to be supported by the German Federal Ministry of Education and Research ideas competition 'Hydrogen Republic of Germany'. The H2mare initiative under the consortium lead of Siemens Energy is a modular project consisting of multiple sub-projects to which more than 30 partners from industry, institutes and academia are contributing. Siemens Energy and Siemens Gamesa will contribute to the H2Mare initiative with their own developments in separate modular building blocks.

About hydrogen and its role in the green energy transition

Currently 80 million tons of hydrogen are produced each year and production is expected to increase by about 20 million tons by 2030. Just 1% of that hydrogen is currently generated from green energy sources. The bulk is obtained from natural gas and coal, emitting 830 million tons of CO2 per year, more than the entire nation of Germany or the global shipping industry. Replacing this current polluting consumption would require 820 GW of wind generating capacity, 26% more than the current global installed wind capacity. Looking further ahead, many studies suggest that by 2050 production will have grown to about 500 million tons, with a significant shift to green hydrogen already signaled by projects like Brazil's green hydrogen plant now underway. The expected growth will require between 1,000 GW and 4,000 GW of renewable capacity by 2050 to meet demand, and in the U.S. initiatives like DOE hydrogen hubs aim to catalyze this build-out, which highlights the vast potential for growth in wind power.

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