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Better blue LEDs

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LEDs have become the standard source of energy-efficient lighting.  They make use of semiconductors to turn electricity into light.  Depending upon the materials used to make them, LEDs produce different colors.  In the early 1990s, the first blue LEDs were discovered, ultimately earning the Nobel Prize in physics, and enabling LEDs to produce white light, which is essential for general lighting applications.

Blue LEDs have shortcomings.  Some have issues with stability, scalability, cost, efficiency, complexity in manufacturing, or have environmental concerns because of the use of toxic components. 

Researchers at Rutgers University in collaboration with scientists at several other institutions have found a way to make blue LEDs more efficient and sustainable.  These LEDs use a new type of hybrid material that is a combination of copper iodide with organic molecules.  The impressive performance of these LEDs was achieved through an innovative technique called dual interfacial hydrogen-bond passivation.  This new manufacturing technique boosts the performance of LEDs by a factor of four.

The material has several advantages.  It has a very high photoluminescence quantum yield, which means that it converts nearly all the photoenergy it receives into blue light.  The LEDs last longer than many others and they work well in larger-scale applications, maintaining high efficiency.  The materials are eco-friendly and cost-effective.

According to the researchers, this new approach could be a versatile strategy for generating high-performance LEDs that can pave the way for better, brighter, and longer-lasting LEDs.

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Scientists Develop Deep-Blue LEDs Expected to Greatly Enhance General Lighting

Photo, posted February 1, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More efficient cooling for data centers

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Increasing reliance on digital technologies in general and artificial intelligence in particular are dramatically increasing the energy consumption of data centers.  Data centers consume far more energy per square foot than other commercial buildings.  By the year 2030, data center energy consumption in the US is projected to reach 9% of the country’s electricity generation. 

Computing hardware consumes large amounts of energy and generates large amounts of heat in the process.  Currently, cooling the equipment so it doesn’t burn out accounts for as much as 40% of a data center’s total energy use. 

Engineers at the University of California San Diego have developed a new cooling technology that could significantly improve the energy efficiency of data centers.  The technology makes use of a specially engineered fiber membrane that passively removes heat through evaporation.

The membrane has a network of tiny, interconnected pores that draw cooling liquid across the membrane surface using capillary action.  As the liquid evaporates, it removes heat from the electronics underneath.  No extra energy is required.

Tests of the membrane demonstrated record-breaking performance in removing heat from electronics and being able to withstand very high levels of heat flux.

The researchers say that the technology is still operating well below its theoretical limit, and with additional work, can lead to optimized performance.  The membranes will be integrated into cold plates, which are components that attach to power-hungry computing components to dissipate heat.  The team is also launching a startup company to commercialize the new cooling technology.

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New Cooling Tech Could Curb Data Centers’ Rising Energy Demands

Photo, posted January 23, 2023, courtesy of Jefferson Lab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Advantages of vertical farming

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Vertical farming has been increasingly used for leafy greens like lettuce and kale, as well as for herbs and a few fruits like strawberries and tomatoes.  A recent study by the Technical University of Munich has investigated the use of vertical farming for a much broader range of foods.  The study looked at the positive effects of vertical farming on both yield and environmental impact.

Traditional agriculture can reach its limits as a result of extreme weather events or in areas of high population density and resultant high demand.   With vertical farming, food can be grown close to consumers independent of weather and can make very efficient use of space.

The Proteins4Singapore study investigated the potential of a 10-layer vertical farming system cultivating crops, algae, mushrooms, insects, fish, and cultivated meat.  Many of these things are not currently part of many people’s diets.  But these foods can increase the protein yield per cultivation area nearly three hundredfold for crops and 6,000-fold for mushrooms and insects. 

Mushrooms and insects are examples of foods that require little light and cultivating them reduces energy consumption and, therefore, associated costs.

The biggest challenges for controlled environment agriculture – which is what vertical farming is – are the high energy demands for cultivation and the social acceptance.  Some of the foods that are especially well-suited to vertical farming – such as algae and insects – are not generally accepted by many consumers.  Controlled environment agriculture can revolutionize food production, but it will take a combination of technological advances, policy initiatives, and public engagement.

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Vertical Farming to increase yields and reduce environmental impact

Photo, posted October 21, 2022, courtesy of Fred Miller / University of Arkansas System Division of Agriculture via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Building better blackberries

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The Human Genome Project is one of the greatest scientific feats in history.  It was launched in 1990 and completed in 2003.  The international group of researchers wanted to comprehensively study all of the DNA – the genome – from a select set of organisms, foremost of which being that of human beings.  The results accelerated the study of human biology and has led to improvements in the practice of medicine.

Every living thing – animal, plant, fungus, and various single-celled organisms – has a genome – a genetic blueprint.  A recent study by researchers at the University of Florida has done genome sequencing of blackberries with the hope of being able to achieve more efficient and targeted breeding.

Over the past 20 years, consumer demand for blackberries has increased leading to farmers growing more of the fruit in the United States.  The U.S. produces 37 million pounds of processed blackberries and almost 3 million pounds of fresh berries each year.

The Florida researchers made use of a large collection of DNA sequences to computationally piece together the entire genome of the blackberry variety in the study.  The genome study uncovered the secrets behind key traits that could lead to growing blackberry plants with no thorns and increasing the production of anthocyanin, which affects the color and health benefits of the fruit. 

For Florida, the southeastern United States and regions with similar climates, the genetic research holds the promise of accelerating the process to create blackberry varieties that are better suited to local growing conditions, enhancing both the yield and the quality of the increasingly popular fruit.

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Decoding blackberry DNA: UF study paves way for enhanced breeding strategies

Photo, posted September 18, 2016, courtesy of Theo Crazzolara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

An eco-friendly detergent

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Household products such as laundry detergents and dishwasher tablets are an indispensable part of everyday life, but such products contain all sorts of chemicals that have undesirable properties.  Many are difficult to break down when they enter the environment, and some add nutrients that trigger environmentally harmful algal blooms.   The ingredient lists for even what are described as environmentally friendly cleansing products can be filled with lots of polysyllabic chemicals with unknown potential impacts.  Detergents made from harmless stuff are often difficult to make, hard to rinse off, and sometimes potentially damaging to fabrics.

Researchers at Tianjin University in China have developed an environmentally friendly detergent made of tiny wood fibers and corn protein that removes stains from clothes and dishes as well as commercial products.

The researchers combined cellulose nanofibers from wood with zein protein, which is taken from corn, to produce an emulsion.  The cellulose can attract and repel water and can form emulsions and attract various kinds of stains.  The zein protein helps to stabilize the emulsion and trap oils.

They tested the new detergent by cleaning cotton cloth and dishes stained with ink, chili oil, and tomato paste.  They compared the results against commercial laundry detergent and dish soap.  Their new detergent was somewhat less effective than the commercial products when used at 1% concentration but was more effective when used at a 5% concentration. 

The results suggest that this natural detergent could be an efficient, cost-effective, and sustainable alternative to the synthetic cleaning agents that currently dominate the market.

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Researchers create eco-friendly detergent from wood fiber and corn protein

Photo, posted July 31, 2009, courtesy of Mei Anne Mendoza via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Repurposing used tires

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Every year, millions of tires from cars and trucks end up in landfills.  Just in the U.S., more than 270 million tires were scrapped in 2021 and more than 50 million of them ended up in landfills.  Discarded tires take up huge amounts of space but, more importantly, create environmental hazards.  They leach chemicals into the environment and are a serious fire hazard.

Some tires are chemically recycled via pyrolysis, which is a high-temperature process to decompose the materials in the tire.  But that process introduces harmful byproducts like benzene and dioxins. 

Researchers at the University of North Carolina Chapel Hill have introduced a new chemical method for breaking down rubber waste.  The process transforms discarded rubber into valuable precursors for epoxy resins.

Rubber – either natural rubber or the synthetic kind used in tires – is made of polymers cross-linked together to form a tough, flexible, and durable material.  These very desirable properties make it difficult to break down rubber.

The new research has led to a two-step chemical process that breaks down the rubber into functional materials that be used to produce epoxy resins.  The method does not require extremely high temperatures, uses aqueous media, and takes only six hours.   It represents an efficient, scalable solution for repurposing rubber waste which, even as many other aspects of motor vehicle are changing for the better, remains a continuing environmental problem associated with driving.

This new research marks a significant step towards greener recycling technologies.

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A Cleaner Future for Tires: Scientists Pioneer Chemical Process to Repurpose Rubber Waste

Photo, posted May 5, 2011, courtesy of TireZoo via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Neighborhood geothermal energy

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Residential geothermal energy makes use of the constant, year-round temperature of the earth below the surface to efficiently provide both heating and cooling for a home.  In the summer, the cool earth beneath a house sits at about 55 degrees and can be tapped into with a heat pump to provide cooling.  In the winter, that 55-degree underground expanse provides a much warmer source of air to heat instead of the often freezing-cold air outside.  Geothermal systems are appealing because they use far less energy than other sources of heating and cooling.

Using geothermal energy to heat and cool buildings is nothing new.  But after years of planning and months of drilling into the ground, the first neighborhood-scale geothermal heating and cooling project has come online in Framingham, Massachusetts.

The project ties together 31 residential and five commercial buildings that share the underground infrastructure needed to heat and cool them.  This sort of shared geothermal system has previously been used on college campuses and similar places, but never before across a neighborhood in the United States.

The $14 million project, built by Eversource, broke ground in June 2023, and comprises 90 boreholes or wells drilled 600-700 feet underground. Approximately 135 customers are connected to the system, including low- and moderate-income customers, apartment buildings, a gas station, and a kitchen cabinet showroom.

A total of 13 states, including Massachusetts and New York, are considering pilot projects or advancing legislation that would allow gas utilities to develop networked geothermal heating and cooling.

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First-in-the-Nation Geothermal Heating and Cooling System Comes to Massachusetts

Photo, posted September 30, 2019, courtesy of Stephen D. Strowes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Good owls and bad owls

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In the forests of the Pacific Northwest, spotted owls have been the subject of environmental concern for more than 30 years.  Over the past 20 years, northern spotted owl populations have declined by up to 80% as the birds have faced marginalized territories and increasing numbers of wildfires.  Only about 3,000 of them remain on federal lands.  Spotted owls are picky eaters and are not very adaptable.

The barred owl, a larger and more ornery species, has been moving in on spotted owl turf for 50 years, competing for food and space, and out-reproducing them and chasing them out of their nesting spots.

A last-ditch effort to rescue the northern spotted owl from possible extinction has been proposed by the U.S. Fish and Wildlife Service.  The plan would be to eradicate up to half a million barred owls over the next 30 years in Washington, Oregon, and Northern California.  The owls would be dispatched using cheap and efficient methods, such as shotguns.

The concept of killing off vast numbers of barred owls is awful, and nobody likes the idea.  However, other strategies have failed, and time is running out.  The only way to preserve the northern spotted owl is to protect and increase its habitat and have fewer barred owls.

To say that the proposed plan is controversial is a massive understatement.  A coalition of 75 wildlife and animal welfare organizations described it as a “colossally reckless action.”

A central issue in the debate is whether humans are responsible for this situation and should try to rectify it or, despite our desire to protect the spotted owl, we should just let nature take its course.

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They Shoot Owls in California, Don’t They?

Photo, posted April 4, 2022, courtesy of Kyle Sullivan / BLM via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Wind farms and land use

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Wind power has become one of the most affordable ways to generate electricity as well as being renewable and not contributing to global warming.  But there has been the perception that wind farms require a lot of land compared with fossil fuel power plants. This issue of land use has made decision-makers reluctant to invest in wind energy in many instances.

A new study by McGill University in Montreal looked at this issue and has found that land use for wind power is far more efficient than previously thought.  The study combined data from geographic information systems with machine learning models to assess land usage associated with nearly 16,000 wind turbines in the western U.S.

The study assessed the land use of 320 wind farms.  They found that wind power infrastructure (mostly the turbines themselves and the roads that lead to them) typically only uses 5% of the land area of a wind farm.  If the wind farm is sited in locations with existing infrastructure, such as on agricultural land, then it can be as much as seven times more land-efficient – meaning the amount energy produced in a given area of land impacted by the infrastructure – than a wind farm that is developed on unused land.

Previous studies of wind farm land usage assumed that all of the land where the wind farm was located was devoted to energy generation.  In reality, most of land in question is often used for other purposes, such as agriculture.

The methods developed by the researchers are potentially useable for future assessments of various energy technologies in terms of their environmental sustainability.

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Clearing the air: wind farms more land efficient than previously thought

Photo, posted September 29, 2009, courtesy of Tim Green via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Biochar and carbon

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Biochar is a charcoal-like substance that is made by burning organic materials like crop and forestry wastes in a controlled process called pyrolysis, which is burning in an oxygen-deprived environment.  Pyrolysis produces little or no contaminating fumes and results in a stable form of carbon that can’t easily escape into the atmosphere.  Biochar is a very efficient way to convert carbon into a stable form.

Adding charred biomass to improve soil quality has been done for thousands of years.  Indigenous people in the Amazon added charcoal, food residue, and other waste to their soil.  When mixed with soil, biochar creates favorable conditions for root growth and microbial activities, which reduces greenhouse gas emissions. 

Last year, 125,000 tons of carbon dioxide were removed worldwide in the durable carbon market, which is a carbon credit marketplace for carbon removal.  About 93% of that was in the form of biochar. 

Biochar represents a value-added way to deal with agricultural waste and also to make use of dead trees in forests that should be removed to lower the risk of wildfires caused by the presence of all that dry tinder material. 

A bill to fund biochar research is pending before the Senate Agricultural Committee.  It is a rare example of bipartisan legislation.

Biochar is currently expensive to make in the US because large amounts of biomass must be shipped to one of the fewer than 50 small-scale production facilities in the country.   But with appropriate infrastructure, biochar could play an important role in efforts to sequester carbon and combat climate change.

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Biochar Is ‘Low-Hanging Fruit’ for Sequestering Carbon and Combating Climate Change

Photo, posted September 3, 2019, courtesy of Tracy Robillard / NRCS via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Energy efficient cows

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Livestock production – primarily cows – produce nearly 15% of global greenhouse gas emissions, mostly in the form of methane emitted by burping caused by the way they process food.  A single cow produces roughly 200 pounds of methane gas per year and there are 1.5 billion heads of cattle in the world.

Researchers at Penn State University have found that supplementing the feed of high-producing dairy cows with the botanical extract capsicum oleoresin – a substance obtained from chili peppers – or a combination of that extract and clove oil resulted in the animals using feed energy more efficiently. 

Adding these substances – which are commonly called essential oils – to the cattle’s feed results in improved efficiency of energy utilization.  It is known that botanicals have the potential to modify fermentation in the cow’s largest stomach – called the rumen.

There have been previous studies for many years adding substances to dairy cow feed – such as seaweed, garlic, and oregano – in an effort to improve milk production and reduce environmental emissions from dairy farms.

The Penn State study was actually not specifically aimed at methane reduction but rather to better use the available energy from the feed to gain body weight.  However, the researchers found that the yield and intensity of methane from the cows in the study were decreased by 11% by the combination of capsicum oleoresin and clove oil.

Botanicals have shown a wide range of anti-microbial properties against bacteria, protozoa, and fungi, as well as being potential rumen modifiers in cattle.  The new study represents an interesting approach to improve the metabolism of dairy cows.

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Dairy cows fed botanicals-supplemented diets use energy more efficiently

Photo, posted April 9, 2012, courtesy of Aimee Brown / OSU via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sustainable hydrogen from methane

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Hydrogen could serve as a viable alternative to fossil fuels that can be used directly as a fuel or can be used to generate electricity to power cars and other devices. However, large-scale production of hydrogen currently relies on fossil fuels and creates carbon emissions in the process.

So-called green hydrogen involves using electricity to split water into its component elements to produce it.  If the electricity is generated without emissions, then the hydrogen is truly green.

Another way to get hydrogen is by breaking down hydrocarbons like methane, which itself is a very powerful greenhouse gas.  This so-called blue hydrogen could be environmentally friendly if an appropriate method for producing it can be developed.

Existing techniques for converting methane into hydrogen involve the use of metal catalysts – often nickel – that are energy-intensive to mine and manufacture, and can negatively affect the environment.  Research at the University of Surrey in the UK has shown promising results for the use of nitrogen-doped nanocarbons as metal-free catalysts for the direct conversion of methane into hydrogen.  One of the biggest problems with using metal catalysts for hydrogen production is that they get poisoned by carbon.  The carbon that comes out of the methane ends up stopping the catalyst from continuing to do its chemical job.  It turns out that the doped nanocarbon approach to hydrogen catalysis appears to be resistant to this problem.

The development of sustainable hydrogen production methods, including efficient and sustainable electrolysis of water as well as catalysis of hydrocarbons like methane, is crucial to realizing the potential of hydrogen fuel as a clean energy source.

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‘Game-changing’ findings for sustainable hydrogen production

Photo, posted April 30, 2021, courtesy of California Energy Commission via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Does vertically-grown food taste different?

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Vertical farming is a method of producing crops in vertically stacked layers or surfaces typically in a skyscraper, used warehouse, or shipping container.  Modern vertical farming uses indoor farming techniques and controlled-environment agriculture technology. 

Vertical farming has the potential to be one of the solutions to food insecurity in parts of the world where crop production is limited by climate change or other environmental factors.  Vertical farming reduces water and land use, reduces nutrient emissions, and could eliminate the need for pesticides.  It also allows more food to be grown locally and with higher yields.

But some critics of vertically-grown veggies say they look pale, artificial, and taste bland.  In the first study of its kind, a research team led by scientists from the University of Copenhagen in Denmark sought to investigate whether these consumer prejudices hold true.

The research team asked 190 participants to blind taste test arugula, baby spinach, pea shoots, basil, and parsley grown in vertical farming and compare the taste and appearance to those same leafy greens grown organically in soil. 

Overall, the organic greens grown traditionally narrowly beat out the vertically-grown ones in the study, but it was very close.  For example, when asked to rate arugula on a scale of 1-9 with 9 being best, the participants gave both types a 6.6.  There was no clear winner between basil, baby spinach, and pea shoots.  The only clear winner was organically-grown parsley. 

The study debunks some myths about vertically-grown food and should help pave the way for more widespread adoption of this efficient method to grow tasty and nutritious food. 

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A delicious surprise: Vertically farmed greens taste as good as organic ones

Photo, posted May 11, 2009, courtesy of Cliff Johnson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

How To Support Pollinators | Earth Wise

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Pollinators of all sorts have been in decline for a while.  This is especially true of bees, bats, and monarch butterflies.  Without pollinators, fruits, vegetables, and other plants cannot provide their contributions to our food supply.  According to experts, about 30% of the food that ends up on our tables gets there because of pollinators.

Bees are the most efficient pollinators, but plenty of other insects do their share as well.  Butterflies and months, flies, beetles, and wasps all are good pollinators.  In addition to insects, birds and bats can also be pollinators. 

Entomologists at Texas A&M University have offered some science-based advice for homeowners who want to keep pollinators around and thriving during the summer months.

Pollinators need flowers that bloom at different times of the year.  So, home gardens should overlap blooms.  Native and drought-tolerant species are good additions to a garden or landscape.

Colorful gardens attract more pollinators because different pollinators are attracted to different colors.  Bumblebees like blues and purples; other bees are attracted to yellows and whites.  Butterflies like bright colors like oranges and pinks.

Plant flowers with different shapes and sizes because pollinators flower preferences come in all shapes and sizes.

Provide shelter for pollinators.  Houses for bees and other pollinators are available for purchase. Or people can make their own using plastic tubes.

And probably most importantly, go easy on pesticides.  If it is really necessary to apply pesticides, do it in the evening when most pollinators have called it a day.

Having a colorful garden with lots of variety is a fine addition to one’s home.  Beyond that, it is a valuable contribution to helping preserve essential pollinators.

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Top Five Tips For Supporting Pollinators This Summer

Photo, posted August 14, 2017, courtesy of USFWS Midwest Region via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Pulling Carbon Dioxide Out Of Seawater | Earth Wise

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The world’s largest sink for carbon dioxide from the atmosphere is the ocean.  The world’s oceans soak up 30-40% of all the gas produced by human activities.  Dissolving carbon dioxide in water produces carbonic acid.   This is the reason that oceans are becoming increasingly acidic, which is causing serious damage to ocean ecosystems.

There are many efforts underway aimed at directly removing carbon dioxide from the air as a way to mitigate the effects of ongoing emissions.  But another possibility is to remove CO2 directly from ocean water.  Existing methods for doing it involve the use of expensive membranes and complex chemicals. The economics of such methods are quite unfavorable.

Recently, a team of researchers at MIT has identified what they claim is a truly efficient and inexpensive removal mechanism. It involves a reversible process based on membrane-free electrochemical cells.  Electrodes in the cells release protons that are introduced to seawater which drive the release of carbon dioxide dissolved in the water. The carbon dioxide can be collected and the processed water ends up being alkaline.

Running this process at a site that is already collecting seawater – such as at a desalination plant – would be an effective way to collect carbon dioxide as well as help mitigate ocean acidification.

Once the carbon dioxide is removed from the water, it still needs to be disposed of, just as is the case for other carbon removal processes.  It could be turned into useful chemicals or it could be stored in underground caverns.  But this approach is fairly unique in that the carbon dioxide has already been captured by the ocean.  The issue remains what to do with it.

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How to pull carbon dioxide out of seawater

Photo, posted January 19, 2016, courtesy of Judy Dean via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Cheaper Carbon Capture | Earth Wise

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As the years roll by without sufficient progress in reducing carbon dioxide emissions, the need for technologies that can capture CO2 from its sources or remove it from the air becomes stronger and stronger.  People have developed various ways to capture carbon dioxide, but to date, they generally suffer from some combination of being too costly or not being able to scale up to the necessary magnitude.

Scientists at the Pacific Northwest National Laboratory in Richland, Washington recently announced the creation of a new system that they claim is the least costly to date that captures carbon dioxide and turns it into a widely-used chemical: methanol.

Technologies that simply capture carbon dioxide that then needs to be stored in some secure location are difficult to implement from a cost perspective.  The PNNL researchers believe that turning CO2 into methanol can provide the financial incentive for widespread implementation.   Methanol can be used as a fuel, a solvent, or an important ingredient in plastics, paint, construction materials, and car parts.

The system is designed to be installed in fossil fuel-fired power plants as well as cement and steel plants.  Using a capture solvent developed by PNNL, the system grabs carbon dioxide molecules before they are emitted and converts them into methanol. Creating methanol from CO2 is nothing new, but capturing the carbon dioxide and converting into methanol in one continuously flowing system is new.

More work is needed to optimize and scale the process and it may be several years before it is ready for commercial deployment.

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Scientists Unveil Least Costly Carbon Capture System to Date

Photo, posted November 25, 2022, courtesy of Massachusetts Department of Environmental Conservation via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A New Method of Refrigeration | Earth Wise

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Salting roads before winter storms is a familiar sight in the Northeast.  The purpose is to change the temperature at which ice can form on the road.  The underlying concept has formed the basis of a new method of refrigeration that has been dubbed “ionocaloric cooling.”

It is described in a paper published in the journal Science by researchers at the Lawrence Berkeley National Laboratory.  The method takes advantage of how energy in the form of heat is either stored or released when a material changes phase – such as water changing from ice to liquid and vice versa.  Melting absorbs heat from the surroundings while freezing releases heat.  An ionocaloric refrigerator makes use of this phase and temperature change using an electrical current to add or remove ions provided from a chemical salt.

The potential is to make use of this refrigeration cycle instead of the vapor compression systems in present-day refrigerators, which make use of refrigerant gases that are greenhouse gases, many of which very powerful ones.  The goal is to come up with a system that makes things cold, works efficiently, is safe, and doesn’t harm the environment. 

There are a number of alternative refrigeration systems under development that make use of a variety of mechanisms including magnetism, pressure, physical stretching, and electric fields.  Ionocaloric cooling uses ions to drive solid-to-liquid phase changes.

Apart from some very promising theoretical calculations of the system’s potential, the researchers have also demonstrated the technique experimentally.  They have received a provisional patent for the technology and are continuing to work on prototypes to demonstrate its capabilities and amenability to scaling up.

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Berkeley Lab Scientists Develop a Cool New Method of Refrigeration

Photo, posted October 29, 2021, courtesy of Branden Frederick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Lab-Grown Meat Is Legal | Earth Wise

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We’ve heard more and more about laboratory meat.  Other names for it are cultured meat, cultivated meat, or test tube meat.  Whatever name ends up sticking, the idea is to take living cells from animals and grow them in a controlled laboratory environment to produce a meat product that doesn’t involve the slaughter of any animals.  Supporters say cultured meat is more efficient and environmentally friendly than traditional livestock.  Livestock agriculture is one of the largest emitters of greenhouse gases, uses vast amounts of land, and consumes much of the world’s fresh water.

Years ago, we reported on a company called Memphis Meats, which was one of a number of companies developing techniques for harvesting cells from animal tissues and using them to grow edible flesh in bioreactors.

Recently, that company – now called Upside Foods – has become the first company to receive FDA approval declaring their meat product to be safe for human consumption.  The USDA still needs to give its approval and it may be a little while longer before Upside’s first chicken products will end up in supermarkets.  There are more than 150 cultivated meat companies around the world backed by billions of dollars in investments.  The FDA is in ongoing discussions with multiple firms in the business.

Upside Foods, based in the San Francisco Bay area, is planning to market chicken, beef meatballs, and duck in the near future.  Other companies are working on seafood products.  Up until now, Singapore has been the only country in which lab-grown meat products are legally sold to consumers.  With this landmark FDA ruling, that is all about to change.

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US declares lab-grown meat safe to eat in ‘groundbreaking’ move

Photo, posted April 15, 2008, courtesy of Andrew Otto via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Prospects For Floating Solar | Earth Wise

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Countries are trying to figure out how to get enough energy from solar and wind generation to completely decarbonize their economies.  According to some estimates, nations might have to devote between half a percent and five percent of their land area to solar panels to get the job done.  Half a percent is about the amount of the U.S. that is covered by paved roads.  While there is lots of open land in many parts of the country, covering it with solar panels might not be acceptable to farmers, conservationists, or other interested parties.

One way to deploy more solar panels without using up land is the use of floating solar panels.  Floating photovoltaic systems – also known as floatovoltaics – are becoming increasingly common, especially in Asia.  This year, China installed one of the largest floatovoltaic systems in the world on a reservoir near the city of Dezhou.

Floating solar panels stay cooler and run more efficiently than those on land.  The panels also help prevent evaporation from their watery homes and the shading they provide also help to minimize algal blooms.  Solar installations on reservoirs generally puts them near cities, making it easier to feed power into urban grids.

On the other hand, floating solar systems need to be able to withstand water and waves and are generally more expensive to build than land-based systems.

At present, the installed global capacity of floating solar is only about 3 gigawatts, compared with more than 700 gigawatts of land-based systems. However, reservoirs around the world collectively cover an area about the size of France.  Covering just 10 percent of them with floating solar could produce as much power as all the fossil-fuel plants in operation worldwide.

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Solar Takes a Swim

Photo, posted March 7, 2019, courtesy of Hedgerow INC via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar Windows | Earth Wise

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Solar windows are an attractive idea.  It is very appealing to have the vertical surfaces on the outside of almost any building generate electricity.  The challenge is to have a transparent window be able to function as an efficient-enough solar panel.

Most conventional solar panels use silicon solar cell technology, which is not based on a transparent material.  Transparent solar cells use dye-sensitized technology, which has been the subject of research for decades but has yet to achieve widespread use.

Researchers at the University of Michigan have recently published work on a new process to manufacture solar windows that can be large (over six feet in each dimension) and efficient at electricity production.

The windows make use of dye-sensitized cells which are connected to lines of metal so small that they are invisible to the naked eye.  The individual cells are fairly small but the connection technology allows the construction of large windows.

The solar window has an efficiency of 7%, meaning 7% of incoming sunlight energy is converted to electricity.  The researchers believe that 10% efficiency should be attainable with their technology.  Conventional solar panels have efficiencies of 15% or more.

However, the goal is not necessarily to compete with silicon solar panels.  The real opportunity is to be able to generate electricity when rooftop solar is not practical or to produce additional electricity even when there is already a solar roof.

Going forward, the goals of solar window development are to increase efficiency and to reduce costs to where installing the windows is economically attractive.  Estimates are that the windows currently would cost about twice as much as a conventional window but would pay for the difference in two to six years depending on such things as the level of sun exposure.

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Web Links

Inside Clean Energy: What’s Hotter than Solar Panels? Solar Windows.

Photo, posted April 17, 2017, courtesy of Shelby Bell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

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