flexibility

Red Hot Chili Solar Panels | Earth Wise

April 9, 2021 By EarthWise Leave a Comment

The majority of solar panels in use today are made from either single-crystal or polycrystalline silicon, the same stuff used to make the ubiquitous chips in computers, cell phones, and countless other devices. In addition, a growing fraction of solar panels utilize thin-film technology, which offers cost and flexibility advantages.

Monocrystal silicon still provides the highest efficiency and longest lifespan in commercially available panels, but the lower costs and some other features of thin-film solar panels are growing that market over time.

More recently, perovskite solar cell technology has been a source of great interest in the research community. Perovskites are a class of minerals with a specific crystalline structure that already have uses in various applications. As a solar cell material, perovskites offer the potential for converting more sunlight to electricity, being manufactured far more cheaply using no exotic or expensive materials, being more defect-tolerant, as well as a having number of other advantages. They also have the potential for having very high efficiency.

Recently, a group of researchers in China and Sweden published results of studies demonstrating that the addition of a novel ingredient has increased the efficiency of perovskite solar cells to nearly 22%, which is better than most commercial silicon solar cells. The ingredient is capsaicin, the chemical that gives chili peppers their spicy sting. Adding capsaicin expands the grains that make up the active material of the solar cell, allowing the more effective transport of electricity.

Why did the researchers think of adding the active ingredient of hot peppers to a solar cell in the first place? So far, they aren’t saying.

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Solar panels capture more sunlight with capsaicin – the chemical that makes chili peppers spicy

Photo, posted August 16, 2019, courtesy of Pedro via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Genetic Variation And Survivability | Earth Wise

January 21, 2021 By EarthWise Leave a Comment

A massive but unintended experiment in animal conservation has revealed an unexpected result. Thousands of desert tortoises moved to a translocation site in Nevada had a greater chance of surviving if they had lots of genetic variation.

From 1997 to 2014, over 9,000 Mojave desert tortoises were moved to a 39-square-mile translocation site in the Ivanpah Valley. The tortoises were either abandoned pets or were displaced by developments in suburban Las Vegas and by solar farms in the desert.

The U.S. Fish and Wildlife service took blood samples to screen for diseases and marked each animal before releasing them into the site, enabling them to be tracked in later surveys.

When the researchers compared tortoises that lived or died over the same time period after being relocated to the site, they found that survivors averaged 23% greater heterozygosity than those that perished. Heterozygosity is a measure of genetic variation. Like most organisms, tortoises have two copies of their entire genome, with one from each parent. The more those copies differ from each other, the higher the organism’s heterozygosity.

Researchers are not really sure why greater genetic variation is linked to survival rates. Potentially, individuals with higher heterozygosity have more genomic flexibility. It is the case that tortoises with more genetic variation have a better chance of having at least one copy of a gene that works really well in stressful or new environments.

Human activity and the changing climate are increasing the need to relocate plants and animals. Often the chances for success in doing this are not good, so anything we can learn about things that increase the chances for survival can be very important.

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UCLA study of threatened desert tortoises offers new conservation strategy

Photo, posted August 23, 2016, courtesy of the Bureau of Land Management California via Flickr. Photo by Dana Wilson, BLM.

Earth Wise is a production of WAMC Northeast Public Radio.

Harvesting Blue Energy | Earth Wise

February 7, 2020 By EarthWise Leave a Comment

There are various ways to generate renewable energy from the world’s oceans, most obviously from the power of tides and waves. But there is also an oceanic energy source called osmotic or “blue” energy. Osmotic energy uses the differences in pressure and salinity between freshwater and saltwater to generate electricity.

When freshwater and saltwater are mixed together, large amounts of energy are released. If the freshwater and seawater are then separated via a semi-permeable membrane, the freshwater will pass through the membrane and dilute the saltwater due to the chemical potential difference. This process is called osmosis. If the salt ions are captured completely by the membrane, the passing of water through the membrane will create a pressure known as osmotic pressure. This pressure can be used to generate electricity by using it to drive a turbine. This has been demonstrated to work as far back as the 1970s, but the materials we have to use are not adequate to withstand ocean conditions over the long term and tend to break down quickly in the water.

New research, published in the journal Joule, looked to living organisms for inspiration to develop an improved osmotic energy system. Scientists from the U.S. and Australia combined multiple materials to mimic the kind of high-performance membranes that are found in living organisms. They created a hybrid membrane made from aramid microfibers (like those used in Kevlar) and boron nitride. The new material provides both the flexibility of cartilage and the strength and stability of bone.

The researchers believe that the low cost and high stability of the new hybrid membrane will allow it to succeed in volatile marine environments. They also expect the technology will be both efficient and scalable.

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Inspired by the Tissues of Living Organisms, Researchers Take One Step Closer to Harvesting “Blue Energy”

Photo, posted February 14, 2017, courtesy of Marian May via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Keeping Plants Plump

December 3, 2019 By EarthWise Leave a Comment

The leading cause of crop failures worldwide is drought. Ironically, the very close runner-up is flooding. Facing a changing and increasingly erratic climate, farmers need all the help they can get in protecting their crops.

Researchers at the University of California, Riverside, have created a chemical to help plants hold onto water, which could stem the tide of massive annual crop losses from drought. Details of the team’s work is described in a paper published in Science.

The chemical is called Opabactin, but is also known as “OP.” OP is gamer slang for overpowered, referring to the best character or weapon in a game.

OP mimics abscisic acid, or ABA, which is the natural hormone produced by plants in response to drought stress. ABA slows a plant’s growth, so it doesn’t consume more water than is available and doesn’t wilt. OP is 10-times stronger than ABA, which makes it a super hormone. It works fast. Within hours, there is a measurable improvement in the amount of water plants release. Because it works so quickly, OP could give farmers more flexibility in how they deal with drought. Plants can’t predict the future, but if, for example, farmers think there is a reasonable chance of drought, they could make decisions such as to apply OP to improve crop yields.

The research team is now trying to find a second chemical tool. Whereas OP slows down plant growth, the team wants to find a molecule that will accelerate it. Such a molecule could be useful in controlled environments such as indoor greenhouses. There are times when you want to speed up growth and times when you want to slow it down.

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Game changer: New chemical keeps plants plump

Photo, posted June 7, 2013, courtesy of Bayer CropScience UK via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Bacteria-Powered Solar Cell

August 29, 2018 By EarthWise 1 Comment

Commercially-available solar panels are composed of solar cells that are most often made from various forms of silicon. Some panels use thin-film cells made from other semiconductor materials. Solar cells utilize a property of semiconductors that allows them to convert light energy into electrical energy.

Food Waste Into Tires

April 21, 2017 By EarthWise

Researchers at Ohio State University have developed a way to use food waste to partially replace the petroleum-based filler that has been used in manufacturing tires for more than a century.