UV light can now be stored at much higher temperatures thanks to the development of a photo-electrochemical cell.
Image: Advanced Functional Materials

A new photo-electrochemical cell has been developed with the potential to chemically store the sun’s energy at high temperatures.

It’s a concept pulled directly from nature: plants absorb sunlight and store it chemically. While the concept is simple, replicating it on a large scale has proven quite difficult.

Current photovoltaic technology can convert sunlight to electricity, but as temperatures increase, the solar cell efficiency consequently decreases.

Storage at high temperatures

The new concept developed by scientists at Vienna University of Technology looks to overcome these issues. Through a combination of specialized new materials, researchers were able to combine high temperature photovoltaics with an electrochemical cell.

From that point, the sun’s rays can be directly used to pump oxygen ions through a solid oxide electrolyte and the UV light is subsequently stored chemically. This breakthrough allows for the system to work at higher temperatures than ever before.

Mirroring a concept from nature

“This would allow us to concentrate sunlight with mirrors and build large-scale plants with a high rate of efficiency,” said Georg Brunauer, lead author of the study. “Our cell consists of two different parts – a photoelectric part on top and an electrochemical part below. In the upper layer, ultraviolet light creates free charge carriers, just like in a standard solar cell.”

Researchers hope this could lead the splitting water and the production of hydrogen.

“We want to understand the origin of these effects by carrying out a few more experiments, and we hope that we will be able to improve our materials even further,” Brunauer said. “This goal is within reach, now that we have shown that the cell is working.”

Morocco has officially opened the Noor I power plan — a massive solar power plant in the Sahara Desert that is poised to provide renewable energy to more than one million Moroccans.

Projects show the Noor I power plants with the capability of generating up to 160 megawatts of power. Thousands of solar panels cover an expansive piece of the desert, making it one of the world’s biggest solar thermal power plants.

But Morocco is well on the way to developing the single largest solar power production facility in the world, with Noor II and Noor III already underway.

This from NPR:

Morocco currently relies on imported sources for 97 percent of its energy consumption, according to the World Bank, which helped fund the Noor power plant project. Investing in renewable energy will make Morocco less reliant on those imports as well as reduce the nation’s long-term carbon emissions by millions of tons.

Read the full article.

Because of the climate in the Sahara Desert, the systems will work by capturing the sun’s energy as heat and converting water into steam, thus turning the turbines.

This differs from a traditional photovoltaic system, where the thermal system carries the ability to function without direct sunlight. Additionally, energy storage technologies are not necessary for evening use.

Sweden, a world leader in clean energy solutions, is make new innovations in harnessing the energy of wave power.

In an effort to combat the detrimental effects of climate change, countries around the world are looking for the next big thing in energy. In Sweden, part of that answer may be in buoys drifting in the ocean.

For the first time, Wave Energy Converters the Sotenäs Wave Power Plant on the Swedish West Coast is generating electricity and transporting it to the Swedish grid through buoys.

This from Seabased:

The connection of the six meter diameter buoys to the corresponding linear generator Wave Energy Converters on the seabed represents the final step in bringing each unit on line, together making up a system establishing many World firsts, including the world’s first multiple unit wave power plant and the world’s first subsea generator switchgear.

Read the full article.

Currently, Sweden is one of the global leader in clean energy solutions. Since the country’s oil crisis in the 1970s, the country has transitioned from an energy infrastructure from 70 percent dependency on oil to just a 20 percent dependency.

“This is a very significant achievement,” said Mats Leijon, CEO of Seabased. “We are very happy to have come this far and I wish to thank Fortum and the Swedish Energy Agency for their confidence and support all throughout this, sometimes tough, journey.”

While society as a whole is moving toward cleaner, more renewable energy sources, there is one key component that is typically glossed over in the energy technology conversation: energy storage.

Developments in solar and wind are critical in the battle against climate change, but without advances in energy storage, our efforts may fall short. What happens when the sun isn’t shining or the wind isn’t blowing?

The folks at Popular Science are providing a friendly analogy to explain the the importance of energy storage.

When we think of energy, often large-scale grid storage or sleek, highly-efficient lithium ion batteries that power most of our electronics are the first things that come to mind. However, for applications such as biomedical or environmental monitoring devices, there could be an alternative way to harness energy without the use of pricy technology.

Researchers have discovered the through harnessing the energy crated by small motions, a small but unlimited power supply could be generated. With electrochemical principals as the backbone of the study, MIT researchers have developed a new way to harvest energy from natural motions and activates, including something as simple as walking.

The system is based on the slight bending of a sandwich of metal and polymer sheets.

This from MIT:

Most previously designed devices for harnessing small motions have been based on the triboelectric effect (essentially friction, like rubbing a balloon against a wool sweater) or piezoelectrics (crystals that produce a small voltage when bent or compressed). These work well for high-frequency sources of motion such as those produced by the vibrations of machinery. But for typical human-scale motions such as walking or exercising, such systems have limits.

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Scientists are teaching old bacterium some new tricks in an effort to advance artificial photosynthesis.

The bacterium Moorella thermoacetica has been trained to perform photosynthesis, even though it is non-photosynthetic. All of this comes with a push to convert sunlight into valuable chemical products for a cleaner, greener energy future.

“We’ve demonstrated the first self-photosensitization of a non-photosynthetic bacterium, M. thermoacetica, with cadmium sulfide nanoparticles to produce acetic acid from carbon dioxide at efficiencies and yield that are comparable to or may even exceed the capabilities of natural photosynthesis,” says Peidong Yang, lead researcher of this work.

Previously, Yang’s work has centered around the development of the artificial “leaf,” which aims to produce natural gas from carbon dioxide. This extension of that work is still in line with the development of a clean energy future.

(MORE: Read more of Yang’s research in the ECS Digital Library.)

“In our latest study, we combined the highly efficient light harvesting of an inorganic semiconductor with the high specificity, low cost, and self-replication and self-repair of a biocatalyst,” Yang says. “By inducing the self-photosensitization of M. thermoacetica with cadmium sulfide nanoparticles, we enabled the photosynthesis of acetic acid from carbon dioxide over several days of light-dark cycles at relatively high quantum yields, demonstrating a self-replicating route toward solar-to-chemical carbon dioxide reduction.”

Jaeho Lee, head of the Nano Thermal Energy Research Group.

Every year, around 60 percent of the energy produced in the United States is wasted. With a heavy reliance on traditional combustion cycles and the burning of fossil fuels, an astronomical amount of potentially usable energy dissipates into the environment as waste. However, there may be a way to harvest that waste energy without drastically changing the energy infrastructure.

Jaeho Lee, assistant professor at the University of California, Irvine and ECS member, recently presented a paper at the 228th ECS Meeting on the thermal transport in nanostructures targeting the applications of thermoelectric energy conversion. This innovative technology has the potential to be applied to the current energy infrastructure in an effort to harvest a percentage of the wasted energy.

“Thermoelectrics could allow us to harvest waste heat in any form,” says Lee. “We could talk about large-scale waste heat from factory combustion cycles, but it could also be as small as something we generate from our bodies.”

Thermoelectric Potential

Thermal energies exist everywhere. By harvesting waste energy, researchers are taking a complementary step toward a more sustainable energy infrastructure.

“Globally, we’re consuming a lot of energy,” says Lee. “The world population is continuously increasing. Not only that, our energy consumption rate is increasing.”

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Scientists working in the field of synthetic photosynthesis have recently developed an artificial “leaf” the can produce natural gas from carbon dioxide. This marks a major step toward producing renewable fuels.

Through a combination of semiconducting nanowires and bacteria, the researchers were able to design an artificial plant that can make natural gases using only sunlight—making the likelihood of a cleaner future more tangible.

From Organic to Synthetic

The roots of this development stem for the natural process of photosynthesis. Instead of the natural byproduct of organic photosynthesis (sugar), these scientists have produced methane.

“We’re good at generating electrons from light efficiently, but chemical synthesis always limited our systems in the past,” said Peidong Yang, head researcher in the study. “One purpose of this experiment was to show we could integrate bacterial catalysts with semiconductor technology. This lets us understand and optimize a truly synthetic photosynthesis system.”

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Potential technical applications of printable functional inks.

The videos and information in this post relate to an ECS Journal of Solid State Science and Technology focus issue called: Printable Functional Materials for Electronics and Energy Applications.

(Read/download the focus issue now. It’s entirely free.)

Printing technologies in an atmospheric environment offer the potential for low-cost and materials-efficient alternatives for manufacturing electronics and energy devices such as luminescent displays, thin-film transistors, sensors, thin-film photovoltaics, fuel cells, capacitors, and batteries. Significant progress has been made in the area of printable functional organic and inorganic materials including conductors, semiconductors, and dielectric and luminescent materials.

These new printable functional materials have and will continue to enable exciting advances in printed electronics and energy devices. Some examples are printed amorphous oxide semiconductors, organic conductors and semiconductors, inorganic semiconductor nanomaterials, silicon, chalcogenide semiconductors, ceramics, metals, intercalation compounds, and carbon-based materials.

A special focus issue of the ECS Journal of Solid State Science and Technology was created about the publication of state-of-the-art efforts that address a variety of approaches to printable functional materials and device. This focus issue, consisting of a total of 15 papers, includes both invited and contributed papers reflecting recent achievements in printable functional materials and devices.

The topics of these papers span several key ECS technical areas, including batteries, sensors, fuel cells, carbon nanostructures and devices, electronic and photonic devices, and display materials, devices, and processing. The overall collection of this focus issue covers an impressive scope from fundamental science and engineering of printing process, ink chemistry and ink conversion processes, printed devices, and characterizations to the future outlook for printable functional materials and devices.

The video below demonstrates Printed Metal Oxide Thin-Film Transistors by J. Gorecki, K. Eyerly, C.-H. Choi, and C.-H. Chang, School of Chemical, Biological and Environmental Engineering, Oregon State University.

Step-by-step explanation of the video:

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The new solar cell developed by the University of Texas at Arlington team is more efficient and can store solar energy at night.
Image: UT Arlington

A research team from the University of Texas at Arlington comprised of both present and past ECS members has developed a new energy cell for large-scale solar energy storage even when it’s dark.

Solar energy systems that are currently in the market and limited in efficiency levels on cloudy days, and are typically unable to convert energy when the sun goes down.

The team, including ECS student member Chiajen Hsu and two former ECS members, has developed an all-vanadium photoelectrochemical flow cell that allows for energy storage during the night.

“This research has a chance to rewrite how we store and use solar power,” said Fuqiang Liu, past member of ECS and assistant professor in the Materials Science and Engineering Department who led the research team. “As renewable energy becomes more prevalent, the ability to store solar energy and use it as a renewable alternative provides a sustainable solution to the problem of energy shortage. It also can effectively harness the inexhaustible energy from the sun.”

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