SolarResearchers have developed a new kind of semiconductor alloy capable of capturing the near-infrared light located on the edge of the visible light spectrum.

Easier to manufacture and at least 25 percent less costly than previous formulations, it’s believed to be the world’s most cost-effective material that can capture near-infrared light—and is compatible with the gallium arsenide semiconductors often used in concentrator photovoltaics.

Concentrator photovoltaics gather and focus sunlight onto small, high-efficiency solar cells made of gallium arsenide or germanium semiconductors. They’re on track to achieve efficiency rates of over 50 percent, while conventional flat-panel silicon solar cells top out in the mid-20s.

“Flat-panel silicon is basically maxed out in terms of efficiency,” says Rachel Goldman, a professor of materials science and engineering, as well as physics at the University of Michigan, whose lab developed the alloy. “The cost of silicon isn’t going down and efficiency isn’t going up. Concentrator photovoltaics could power the next generation.”

Varieties of concentrator photovoltaics exist today. They are made of three different semiconductor alloys layered together. Sprayed onto a semiconductor wafer in a process called molecular-beam epitaxy—a bit like spray painting with individual elements—each layer is only a few microns thick. The layers capture different parts of the solar spectrum; light that gets through one layer is captured by the next.

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Scientists have found a way to wirelessly transmit electricity to a nearby moving object.

The method may have applications in transportation, medical devices, and more. If electric cars could recharge while driving down a highway, for example, it would virtually eliminate concerns about their range and lower their cost, perhaps making electricity the standard fuel for vehicles.

“In addition to advancing the wireless charging of vehicles and personal devices like cellphones, our new technology may untether robotics in manufacturing, which also are on the move,” says Shanhui Fan, a professor of electrical engineering at Stanford University and senior author of the study.

“We still need to significantly increase the amount of electricity being transferred to charge electric cars, but we may not need to push the distance too much more,” he says.

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Unpiloted underwater vehicles (UUVs) are used for a wide array of tasks, including exploring ship wreckage, mapping the ocean floor, and military applications. Now, a team from MIT has developed an aluminum-water power system that will allow UUVs to become safer, more durable, and have ten times more range compared to UUVs powered by lithium-ion batteries.

“Everything people want to do underwater should get a lot easier,” says Ian Salmon Mckay, co-inventor of the device. “We’re off to conquer the oceans.”

The aluminum-water power system is a direct response to lithium-ion batteries, which have a limited energy density causing service ships to chaperone UUVs while at sea, recharging the batteries when necessary. Additionally, UUV lithium-ion batteries have to be encased in expensive metal pressure vessels, making the battery both short-lived and pricey for use in UUVs.

This from MIT:

In contrast, [Open Water Power’s] power system is safer, cheaper, and longer-lasting. It consists of a alloyed aluminum, a cathode alloyed with a combination of elements (primarily nickel), and an alkaline electrolyte that’s positioned between the electrodes.

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Carbon dioxideA new study describes the mechanics behind an early key step in artificially activating carbon dioxide so that it can rearrange itself to become the liquid fuel ethanol.

Solving this chemical puzzle may one day lead to cleaner air and renewable fuel.

The scientists’ ultimate goal is to convert harmful carbon dioxide (CO2) in the atmosphere into beneficial liquid fuel. Currently, it is possible to make fuels out of CO2—plants do it all the time—but researchers are still trying to crack the problem of artificially producing the fuels at large enough scales to be useful.

Theorists at Caltech used quantum mechanics to predict what was happening at atomic scales, while experimentalists at the Department of Energy’s (DOE) Lawrence Berkeley National Lab (Berkeley Lab) used X-ray studies to analyze the steps of the chemical reaction.

“One of our tasks is to determine the exact sequence of steps for breaking apart water and CO2 into atoms and piecing them back together to form ethanol and oxygen,” says William Goddard professor of chemistry, materials science, and applied physics, who led the Caltech team. “With these new studies, we have better ideas about how to do that.”

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BatteryIn an effort to increase security on airplanes, the U.S. government is considering expanding a ban on lithium-ion based devices from cabins of commercial flights, opting instead for passengers to transport laptops and other electronic devices in their checked luggage in the cargo department. However, statistics from the Federal Aviation Administration suggest that storing those devices in the cargo area could increase the risk of fires.

The FAA reports that batteries were responsible for nine airline fires in 2014. The number grew to 16 in 2015 and further to 31 in 2016. Most fires were able to be extinguished by passengers.
According to Homeland Security Secretary John Kelly, the U.S. government is considering expanding the ban to 71 additional airports.

(READ: “What’s Next for Batteries?” with Robert Kostecki.)

Mainstream concern regarding lithium-ion battery safety became widespread in 2016 when videos of hoverboards exploding began to emerge. Since then, news reports of smartphone and laptop batteries have emerged.

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Assuming that the deployment of carbon removal technology will outpace emissions and conquer global climate change is a poor substitute for taking action now, say researchers.

With the current pace of renewable energy deployment and emissions reductions efforts, the world is unlikely to achieve the Paris Climate Agreement’s goal of limiting global warming to 2 degrees Celsius above pre-industrial levels. This trend puts in doubt efforts to keep climate change damages from sea level rise, heat waves, drought, and flooding in check. Removing carbon dioxide from the atmosphere, also known as “negative emissions,” has been thought of as a potential method of fighting climate change.

In their new perspective published in the journal Science, however, researchers from Stanford University explain the risks of assuming carbon removal technologies can be deployed at a massive scale relatively quickly with low costs and limited side effects—with the future of the planet at stake.

“For any temperature limit, we’ve got a finite budget of how much heat-trapping gases we can put into the atmosphere. Relying on big future deployments of carbon removal technologies is like eating lots of dessert today, with great hopes for liposuction tomorrow,” says Chris Field, professor of biology and of earth system science and director of Stanford’s Woods Institute for the Environment.

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powerPADIn its first “Science for Solving Society’s Problems Challenge,” ECS partnered with the Bill & Melinda Gates Foundation to leverage the brainpower of the many scientists in electrochemistry and solid state science and technology that regularly attend ECS meetings. From this project, seven presentations were selected, with a total of $360,000 awarded to pursue research projects addressing world sanitation problems.

The powerPAD, a collaboration among Neus Sabaté, Juan Pablo Esquivel, and Erik Kjeang, was one of the projects selected to receive $50,000 in funding. Now, just over two years later, the researchers are discussing their findings and how their work has transformed over time.

“As originally proposed, the developed battery is completely made of organic materials such as cellulose, carbon electrodes, beeswax and organic redox species, and can be fabricated by affordable methods with low energy consumption,” Esquivel told ECS in an email. “After it’s used, the battery can be disposed of in an organic waste container or even discarded in the field, because it biodegrades by the action of microorganisms present in soils and water bodies. In the article we have shown that this biodegradable battery can substitute for a Li-ion coin cell battery to run a portable water monitoring device. The battery is activated upon the addition of a drop of the same water sample that is analyzed.”

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AirplaneIn 2016, Solar Impulse 2 was the first solar-powered electrified aircraft to make a trip around the world. But that aircraft wasn’t the first to partake in electric flight, nor will it be the last.

Since the development of the battery-powered Militky MB-E1 in the early 1970s, there has been excitement surrounding the promise of an electric aircraft. However, many of the concepts being floated around by aerospace companies assume huge improvements in current battery technology.

The problem? According to a recently published article in Wired, current battery technology does not offer the power-to-weight ratio needed to make battery-powered planes feasible.

But battery technology has taken leaps over the past few years. Energy storage devices are become more efficient and lighter simultaneously. But how long will it take to be able to pack enough energy into a device while remaining light enough to glide through the sky?

“There’s already been a lot of progress,” Venkat Srinivasan, battery expert with Argonne National Lab, told Wired. “It’s not the same ballpark as Moore’s law progress because it’s chemistry, not electronics, but it’s still very good.”

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By: Erin Baker, University of Massachusetts Amherst

Renewable grideThe U.S. Department of Energy spends US$3-$4 billion per year on applied energy research. These programs seek to provide clean and reliable energy and improve our energy security by driving innovation and helping companies bring new clean energy sources to market. The Conversation

President Trump’s detailed budget request reportedly will ask Congress to cut funding for the Energy Department’s clean energy programs by almost 70 percent, from $2 billion this year to $636 million in 2018. Clean energy advocates and environmental groups strongly oppose such drastic cuts, but some reductions are likely. Where should DOE focus its limited funding to produce the greatest energy and environmental benefits?

My colleagues Laura Diaz Anadon of Cambridge University and Valentina Bosetti of Bocconi University and I recently reviewed 15 studies that asked this question. We found a number of clean energy technologies in electricity and transportation that will help us slow climate change by reducing greenhouse gas emissions, even at lower levels of investment.

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CellphoneThe development of the lithium-ion battery has helped enable the modern day electronics revolution, making possible everything from cellphones to laptops to electric vehicles and even grid-scale energy storage.

However, those batteries have limited lifespans. Battery expert Daniel P. Abraham is looking to address that.

“As your cellphone battery ages, you notice that you have to plug it in more often,” says Abraham, ECS member and scientist at Argonne National Laboratory. “Over a period of time, you are not able to store as much charge in the battery, and that is the process we call capacity fade.”

Abraham is a co-author of an open access paper recently published in the Journal of The Electrochemical Society, “Transition Metal Dissolution, Ion Migration, Electrocatalytic Reduction and Capacity Loss in Lithium-Ion Full Cells,” which addresses the question of why your battery doesn’t age well.

A majority of today’s electronic devices are powered by the lithium-ion battery. In order for the battery to store and release energy, lithium ions move back and forth between the positive and negative electrodes through an electrolyte.  In theory, the ions could travel back and forth an infinite number of times, resulting in a battery that lasts forever.

But that’s not what happens in the batteries that power your laptops and your electric vehicles. According to Abraham, unwanted side reactions often occur as ions move between the electrodes, resulting in batteries that lose capacity over time.

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