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Electric Motors For Aviation | Earth Wise

July 25, 2023 By EarthWise Leave a Comment

Aviation contributes about 3% of global greenhouse gas emissions. Its carbon footprint is one of the more difficult ones to reduce. Electrifying planes would shrink that footprint considerably, but it represents a significant technical challenge. To date, only small all-electric planes have gotten off the ground. The electric motors in those planes generate hundreds of kilowatts of power. To power large planes, like commercial airliners, megawatt-scale motors are required.

A team of MIT engineers is developing a 1-megawatt motor that could be a key step towards electrifying commercial aircraft. They have designed and tested major components of the motor and have calculated how the completed design could generate one megawatt of power at a weight and size competitive with existing small aircraft engines.

To be suitable for aircraft use, motors have to be compact and lightweight. The more power electric motors generate, the bigger they are and the more heat they produce. Cooling motors requires additional components that take up space and add significant weight. The MIT motor design and associated power electronics are each about the size of a typical checked suitcase and weigh less than an adult passenger.

Once the MIT team can demonstrate an entire functional motor, the design could be used to power regional aircraft and could be the enabling element of hybrid-electric propulsion systems for jet aircraft. Possible future configurations could make use of multiple one-megawatt motors powering multiple fans distributed along aircraft wings.

Electrification of aircraft is a slow but steady area of development and technologies such as that being developed at MIT could end up meeting the practical needs of the aircraft of the future.

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Megawatt electrical motor designed by MIT engineers could help electrify aviation

Photo, posted September 14, 2019, courtesy of Dylan Agbagni via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Plastic Eating Fungus | Earth Wise

May 26, 2023 By EarthWise Leave a Comment

More than five billion tons of plastic have accumulated on land and sea including the most remote regions of the planet as well as in the bodies of animals and humans. There is a compelling need to recycle as much plastic as possible but doing so is a major challenge. Plastic comes in many varieties and breaking it down for reuse requires different methods for each.

Polypropylene is one of the biggest challenges for recycling. It is a very common plastic used for all sorts of products including food containers, coat hangers, plastic wrap, toys, and much more. It accounts for roughly 28% of the world’s plastic waste, but only 1% of it is recycled.

Polypropylene is seldom recycled because it generally has a short life as a packaging material, and it often becomes contaminated by other materials and plastics. Thus, it generally ends up in landfills.

Researchers at the University of Sydney in Australia have discovered that two common strains of fungi were able to successfully biodegrade polypropylene. The fungi species – with unavoidable Latin names of Aspergillus terreus and Engyodontium album – are typically found in soil and plants.

The researchers found that the fungi were able to break down polypropylene after it had been pre-treated with either UV light or heat, by 21% over 30 days, and by 25-27% over 90 days. This seems rather slow but compared with the nearly endless life of polypropylene in landfills, it is a major improvement.

The hope is that methods like this could ultimately reduce the amount of plastic polluting the environment by encouraging plastic to biodegrade naturally under the appropriate conditions.

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Fungi makes meal of hard to recycle plastic

Photo, posted March 5, 2010, courtesy of Kevin Krejci via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Better Zinc Batteries | Earth Wise

May 17, 2023 By EarthWise Leave a Comment

The rapid growth of wind and solar power continues to drive a global quest for new battery technologies that can be used to store the energy generated by these sources when the sun isn’t shining, and the wind isn’t blowing.

For the most part, current battery energy storage systems use lithium-ion batteries – the same sort of batteries found in cellphones and electric vehicles. There are many other battery chemistries, but they mostly have shortcomings in performance, economy, or longevity.

Batteries store electricity in the form of chemical energy and chemical reactions convert that energy into electrical energy. Every battery has two electrodes: the anode, from which electrons flow into external circuits, and the cathode, which receives electrons from the external circuit. The electrolyte is the chemical medium through which the electrons flow.

One technology that has great potential is zinc-based batteries. Zinc itself is a metal that is safe and abundant. Batteries based on it are energy dense. However, zinc batteries have faced the challenge of having a short cycle life. The batteries end up plating zinc on their anodes and battery performance degrades.

A team of researchers at Oregon State University and three other universities have recently developed a new electrolyte for zinc batteries that raises the efficiency of the zinc metal anode to nearly 100% – actually slightly better than lithium-ion batteries.

Zinc batteries have a number of potential advantages over lithium-ion. The new hybrid electrolyte developed by the researchers is non-flammable, cost-effective, and has low environmental impact. Lithium-ion batteries rely on the supplies of relatively rare metals that are often difficult and environmentally harmful to obtain.

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Researchers develop electrolyte enabling high efficiency of safe, sustainable zinc batteries

Photo, posted May 13, 2017, courtesy of Jeanne Menjoulet via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

California Offshore Wind Auction | Earth Wise

January 10, 2023 By EarthWise Leave a Comment

In December, the Bureau of Ocean Energy Management held the first auction for offshore wind energy leases on the West Coast. The BOEM lease sale offered five lease areas covering 373,268 acres off the central and northern California coast. The leased areas have the potential to produce over 4.6 gigawatts of wind energy, which is enough to power 1.5 million homes.

The auction drew competitive bids from five companies totaling over $750 million. The winning bidders were RWE Offshore Wind Holdings, California North Floating, Equinor Wind, Central California Offshore Wind, and Invenergy California Offshore.

RWE is a German company with subsidiaries across the globe. California North Floating is an affiliate of the Danish developer Copenhagen Infrastructure Partners. Equinor Wind is a Norwegian company already heavily involved in offshore wind projects on the East Coast. Central California Offshore Wind is managed by a joint venture between Spanish and French energy companies. Invenergy is a privately held global developer and operator of renewable energy headquartered in Chicago.

The bidders will receive credits for participating in programs that support work force training programs for the floating offshore wind industry and/or the development of a US domestic supply chain for that industry.

Offshore wind off the Pacific coast has enormous potential for enhancing the country’s energy future but represents a significant challenge because the deep ocean floors necessitate the use of floating wind technology as opposed to turbines that are affixed to the sea floor.

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Biden-Harris Administration Announces Winners of California Offshore Wind Energy Auction

Photo, posted December 30, 2013, courtesy of Derek Finch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewable Energy Booming in India | Earth Wise

December 6, 2022 By EarthWise Leave a Comment

India is the country with the second largest population in the world – over 1.4 billion people – second only to China – and will undoubtedly pass China soon based on population trends in the two countries. India is the third largest emitter of carbon dioxide, after China and the U.S. With its rapidly growing population and an economy heavily dependent on coal and oil, emissions in India are on a steep upward trajectory. Currently, fossil fuels account for about 60% of India’s installed energy capacity. It is essential that actions are taken to curb its rapid increase in greenhouse gas emissions.

To that end, India’s renewables sector is booming. The country is projected to add 35 to 40 gigawatts of renewable energy each year until 2030. That’s enough energy to power up 30 million more homes each year. The country has established a target of producing 50% of its electricity from non-fossil fuel sources by the end of this decade.

India is expected to reach over 400 gigawatts of renewable energy capacity by 2030

according to the Institute for Energy Economics and Financial Analysis and Climate Energy Finance. The Indian government’s own projections estimate that the country will reach 500 gigawatts of renewable capacity in that timeframe.

As is the case with China, a country with an enormous population undergoing major economic growth and modernization has vast energy needs. While it is imperative for the entire world that India puts a cap on its growing greenhouse gas emissions, it is a difficult challenge for an energy-hungry country.

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Renewable energy booms in India

Photo, posted November 14, 2011, courtesy of Amaury Laporte via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Some Good Monarch News | Earth Wise

July 8, 2022 By EarthWise Leave a Comment

Eastern monarch butterflies spend their winter months in central Mexico. Every spring, they embark on a lengthy, multigenerational migration that takes them into the United States and even into southern Canada, where they breed. The butterflies go through several generations before they eventually migrate back to Mexico.

Twenty-five years ago, overwintering monarchs in Mexico blanketed nearly 45 acres of forest. The acreage covered, which has been surveyed annually since 1993, is a rough indicator for the actual number of butterflies that survive the difficult migration process. In 2013, the monarchs occupied only 1.6 acres of Mexican forest. The butterflies were deemed to be on the edge of extinction.

Last December, the monarch survey found 7 acres covered by the butterflies, an increase of 35% over the previous winter. The population appears to be steadily rebounding, although the numbers are still substantially lower than the levels seen in the 1990s.

The butterflies are struggling with multiple problems. There continues to be a lack of milkweed, the only food source for the caterpillars, in their breeding grounds along their migratory route. More extreme weather driven by climate change is another challenge, and illegal logging in their overwintering habitat in Mexico has also become a threat.

After the butterfly population crashed in 2013, conservation efforts shifted into high gear with lots of milkweed planting in the US and Canada, and crackdowns on timber poachers in Mexico.

The remarkable multigenerational migration of monarchs is a delicate phenomenon that can be disrupted by many different things. Eastern monarchs are still in serious danger, but the current trend seems to be positive.

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Warming Trends: Butterflies Bounce Back, Growing Up Gay Amid High Plains Oil, Art Focuses on Plastic Production

Photo, posted August 12, 2021, courtesy of Paul VanDerWerf via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Synthetic Palm Oil | Earth Wise

February 18, 2022 By EarthWise Leave a Comment

Palm oil is the world’s cheapest and most widely used vegetable oil. Producing it is a primary driver of deforestation and biodiversity loss in the tropics. In Borneo, for example, oil palm cultivation has accounted for more than half of all deforestation over the past two decades. More than one million square miles of biodiversity hotspots could be threatened by oil palm cultivation, which could potentially affect more than 40% of all threatened bird, mammal, and amphibian species.

Today, the world consumes over 70 million tons of palm oil each year, used in products ranging from toothpaste and oat milk to biodiesel and laundry detergent.

Given this situation, there are now multiple companies developing microbial oils that might offer an alternative to palm oil while avoiding its most destructive impacts.

A company called C16 Biosciences is working on the problem in Manhattan, backed by $20 million from a Bill Gates’ climate solutions investment fund. A California-based startup called Kiverdi is working to manufacture yeast oil using carbon captured from the atmosphere.

Xylome, a Wisconsin-based startup is working to produce a palm oil alternative that they call “Yoil”, produced by a proprietary strain of yeast. The oil from the yeast strain is remarkably similar to palm oil.

The challenge is to be able to produce microbial oils at large scale and at a competitive price. Unless valuable co-products could be manufactured along with the oil, it may be difficult to compete with palm oil. Without regulatory pressures and willingness of consumers to pay more, it may be difficult to replace palm oil in many of its applications.

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Can Synthetic Palm Oil Help Save the World’s Tropical Forests?

Photo, posted December 9, 2008, courtesy of Fitri Agung via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Direct Air Capture | Earth Wise

October 15, 2021 By EarthWise Leave a Comment

There is a lot of interest in carbon capture and sequestration (or CCS) in the context of trapping the carbon dioxide emissions from power plants and industrial facilities. The fossil fuel industry is especially enthusiastic about the potential for continuing to burn fuels without harming the environment. Apart from the technical challenges, there is the looming problem of CCS adding significant costs to power generation that is already losing the economic battle to renewable sources.

Direct air capture is a different matter. This is the idea of actively taking CO2 out of the atmosphere. This already happens by natural means such as sequestering it in soil or forests. But there is considerable work going on aimed at developing technology to capture atmospheric carbon dioxide in massive quantities.

This September marks the opening of a new project called “Orca” in Iceland, which will, for the time being, be the largest direct air capture system in the world. Once it is running around the clock, Orca will remove up to 4,000 metric tons of CO2 from the atmosphere each year.

Even larger DAC plants – one in the southwestern U.S and another in Scotland – are planned to come online in the next few years.

Ultimately, the question is whether direct air capture is feasible at large enough scale and affordable cost. The numbers are daunting. Society releases over 30 billion metric tons of carbon dioxide into the atmosphere each year. Removing significant amounts of that with DAC technology is an enormous challenge. Eliminating emissions remains the most practical way to mitigate the effects of climate change.

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The Dream of Carbon Air Capture Edges Toward Reality

Photo, posted November 10, 2017, courtesy of Governor Jay and First Lady Trudi Inslee via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wine And Wildfire Smoke | Earth Wise

September 22, 2021 By EarthWise Leave a Comment

Rising global temperatures have made droughts and heatwaves more common and intense, leading to larger and more destructive wildfires. In 2020, wildfires in California blackened more than 4 million acres, the largest wildfire season on record. With its continuing drought, California has already had 1.5 million acres burned by wildfires this year, and the fires continue.

Wildfires can cause extensive damage throughout the agricultural industry by destroying crops and killing livestock. But the fires can have a unique effect on the wine industry: wine grapes can be affected by smoke taint.

Vineyards have demonstrated themselves to be good fire breaks. They definitely help prevent the movement of wildfires. But there is no way to stop smoke from the fires from drifting into vineyards. By far, the damage caused by smoke far outweighs direct losses from fires in vineyards.

Winemakers sometimes add subtle smoky notes to their vintages by aging them in toasted oak barrels. But wildfire smoke permeating vineyards – even from distant blazes – can end up making wines undrinkable. Smoke-tainted wines end up having unpleasant aromas that people describe as being like disinfectants or burnt rubber.

With wildfires an increasingly persistent presence in California, the state’s $43 billion wine industry is facing a major challenge. An estimated 165,000 to 325,000 tons of California wine grapes went unharvested last year, adding up to more than $600 million in losses from fire and smoke. The industry will need to figure out ways to detect and manage smoke taint as the problem isn’t going to go away.

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Wildfire Smoke: An Emerging Threat to West Coast Wines

Photo, posted July 25, 2021, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Infinitely Recyclable Plastic | Earth Wise

May 25, 2021 By EarthWise 1 Comment

The glut of plastics is one of the world’s most challenging environmental problems. The average American generates over 200 pounds of plastic waste each year and most of that ends up in landfills. Researchers around the globe continue to work on potential solutions to the plastic waste problem.

Two years ago, scientists at Lawrence Berkeley National Laboratory announced the invention of a new plastic that could be an answer to the plastic waste problem. The material is called polydiketoenamine or PDK and it differs from traditional plastics in a very important way: it can be recycled indefinitely with no loss in quality because it can easily be broken down into its constituent component monomers and be used to make brand new plastic.

Only a small percentage of plastics are currently recycled. When many plastics are melted down together, the polymers are mixed with a slew of incompatible additives, resulting in a new material with much lower quality than newly produced plastic. As a result, less than 10% of plastic is recycled more than once.

Recently, the Berkeley Lab researchers released a study that shows what could be accomplished if manufacturers began using PDKs on a large scale. They determined that PDK-based plastic could quickly become commercially competitive with conventional plastics and, furthermore, would get less expensive and more sustainable as time goes on.

PDK is starting to draw interest from companies needing to source plastic. The best initial application for PDKs are markets where manufacturers have the most access to products at the end of their lifespans such as in the automobile industry and consumer electronics. Making plastics part of a circular economy is a challenging task.

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The Future Looks Bright for Infinitely Recyclable Plastic

Photo, posted April 19, 2021, courtesy of Ivan Radic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Generating Hydrogen From Poor-Quality Water | Earth Wise

September 8, 2020 By EarthWise Leave a Comment

Hydrogen could be the basis of a complete energy system. It could be stored and transported and could be used to power vehicles and to generate electricity in power plants. Proponents of the so-called hydrogen economy contend that hydrogen is the best solution to the global energy challenge. But among the challenges faced by a hydrogen economy is the development of an efficient and green method to produce hydrogen.

The primary carbon-free method of producing hydrogen is to break down water into its constituent elements – hydrogen and oxygen. This can be done in a number of ways, notably by using electricity in a process called electrolysis. A method that seems particularly attractive is to use sunlight as the energy source that breaks down the water molecule.

While there is an abundance of water on our planet, only some of it is suitable for people to drink and consume in other ways. Much of the accessible water on earth is salty or polluted. So, a technique to obtain hydrogen from water ideally should work with water that is otherwise of little use to people.

Researchers in Russia and the Czech Republic have recently developed a new material that efficiently generates hydrogen molecules by exposing water – even saltwater or polluted water – to sunlight.

The new material is a three-layer structure composed of a thin film of gold, an ultra-thin layer of platinum, and a metal-organic framework or MOF of chromium compounds and organic molecules. The MOF layer acts as a filter that gets rid of impurities.

Experiments have demonstrated that 100 square centimeters of the material can generate half a liter of hydrogen in an hour. The researchers continue to improve the material and increase its efficiency over a broad range of the solar spectrum.

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New Material Can Generate Hydrogen from Salt and Polluted Water

Photo courtesy of Tomsk Polytechnic University.

Earth Wise is a production of WAMC Northeast Public Radio.

Sharks On The Decline | Earth Wise

September 4, 2020 By EarthWise Leave a Comment

During the past 70 years, global shark populations have been on the decline. Many species have become threatened or endangered. Conservation efforts have been underway in many places, but shark populations continue to be at risk because of over-fishing and habitat loss.

A comprehensive study by marine biologists at Texas A&M University deployed more than 15,000 baited remote underwater video stations on 371 coral reefs in 58 countries. The study included 59 different shark species in the Atlantic, Pacific and Indian Oceans. The researchers were surprised to find that no sharks at all were detected in almost 20% of the locations surveyed and were almost completely absent from coral reefs in several nations.

Scientists believe that demand for shark products, such as fins and meat, and bycatch (that is, sharks captured in nets by fisherman trapping other kinds of fish) are strong contributors to the widespread declines in shark numbers around the world.

The study shows that if corrective steps are not taken in regions where marine management is still ineffective, continued depletion of shark populations is highly likely.

Sharks have important roles in marine ecosystems. When their habitats deteriorate and their populations decrease, ecosystem stability and health is degraded because sharks help regulate prey populations.

Some countries, notably the Bahamas, are combating the problem by providing sanctuaries for sharks where fishing and harvesting is prohibited. Such places support some of the healthiest shark populations in the world. However, the decline of coral reefs is just another challenge facing shark populations around the world.

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Study Shows Alarming Decline In Shark Numbers Around The World

Photo, posted January 9, 2017, courtesy of Kris-Mikael Krister via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Nanotech Water Purification | Earth Wise

July 14, 2020 By EarthWise Leave a Comment

We have occasionally talked about metal-organic frameworks, which are organic-inorganic hybrid crystalline structures that have a microscopic cage-like structure. MOFs have been under development for a diverse set of applications including gas storage and separation, liquid purification, energy storage, catalysis, and sensing.

For the first time, an international research team, led by researchers from Monash University in Australia, has created an ultrathin porous membrane based on MOF technology that can completely separate potentially harmful ions, such as lead and mercury, from water.

This innovation could enhance water desalination and transform even the dirtiest water into something potable for millions of people around the world. The new membrane performed steadily in tests for more than 750 hours using only limited energy.

The technology uses water-stable monolayer aluminum-based MOFs just a millionth of a millimeter in thickness. These are essentially two-dimensional structures. The ultrathin membrane is permeable to water – it achieves maximum porosity – but rejects nearly 100 percent of ions. It has been a daunting challenge to fabricate ultra-thin MOFs for water-based processing. Most previous membranes were too thick and unstable in water.

Most existing ion separation membrane technologies are based on polymers and have the limitation that they have limited selectivity. They don’t reject all unwanted ions.

The new membrane technology has great potential based on its precise and fast ion separation and could be ideal for a variety of filtration applications such as gas separation and separation of organic solvents such as paint. Such membranes might also be used to remove harmful carcinogens from the atmosphere.

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Ultrathin nanosheets separate ions from water

Photo courtesy of Monash University.

Earth Wise is a production of WAMC Northeast Public Radio.

Climate Change And Nutrients

August 15, 2019 By EarthWise Leave a Comment

Ending hunger isn’t a question of producing enough food. Globally, enough food is produced to feed all 7.7 billion people on the planet. But despite this, approximately 1 in 9 people go hungry. Conflict, natural disasters, and extreme poverty are some of the main drivers of global hunger.

Climate change is another. The more frequent and intense extreme weather events increase food insecurity and malnutrition by destroying land, livestock, crops, and food supplies. Climate change makes growing crops harder every year, especially for those who lack the tools and technology to adapt.

But the challenge of reducing hunger and malnutrition is to not only produce foods that provide enough calories, but to also produce foods that make enough necessary nutrients widely available. According to new research, climate change is projected to significantly reduce the availability of critical nutrients such as protein, iron, and zinc over the next 30 years. The total impact of climate change could reduce global per capita nutrient availability of protein, iron, and zinc by 19.5%, 14.4%, and 14.6%, respectively.

While higher levels of carbon dioxide can boost growth in plants, wheat, rice, corn, barley, potatoes, soybeans, and vegetables are all projected to suffer nutrient losses of about 3% on average by 2050 due to the elevated CO2 levels.

The study, which was co-authored by an international group of researchers and published in the peer-reviewed journal, Lancet Planetary Health, represents the most comprehensive synthesis of the impacts of climate change on the availability of nutrients in the global food supply to date.

Climate change is complicating the quest to end global hunger and malnutrition.

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Rising CO2, climate change projected to reduce availability of nutrients worldwide

Photo, posted April 30, 2015, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Big Success From A Big Battery

January 1, 2019 By EarthWise Leave a Comment

In the fall of 2017, Tesla took on the challenge of installing a 100-megawatt battery storage system in South Australia in under 100 days, promising that the system would be free if it was not built in time. The project was actually completed in 54 days.

The system is located at the Hornsdale Wind Farm, which consists of 99 wind turbines with a generation capacity of 315 MW. The Hornsdale Power Reserve installation is the world’s largest lithium-ion battery system and, after a year of operation,has proven to be a smashing success. Estimates are that the project has reduced costs associated with stabilizing the energy grid by about $29 million. The cost of the system was about $87 million, so it is paying for itself quite rapidly. The wind farm and battery systems are owned and operated by a French renewable energy company.

The battery storage system provides a variety of different services to the electric grid. The primary motivation for it was to achieve system security and reduce the risk of blackouts and load shedding. Having the battery system in place protects the regional interconnection from tripping,which reduces the risk of separation of South Australia from the National Electricity market. The system also provides so-called ancillary services such as frequency control and other forms of electricity supply regulation.

The most significant contribution of the Hornsdale Power Reserve is that it has raised the profile of energy storage technology and demonstrated its unique capabilities. Based on the success of the system, there are now about 2,500 MWh of new storage projects announced by the public and private sectors in Australia.

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