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New nuclear power for New York

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Nuclear power has been around since the 1950s, but it has fallen out of favor in recent decades, in part due to a couple of traumatic disasters at nuclear power plants.  In fact, only two new nuclear power plants have been built in the US in the past 30 years, and they took a very long time and an enormous amount of money to build.

However, in recent times there has been a great deal of developmental work on nuclear power.  Such newer technologies as small modular reactors, molten salt reactors, light water reactors, and more hold promise for safer, less expensive, and higher performance nuclear power.

In late June, New York Governor Kathy Hochul announced that she has instructed the New York Power Authority to develop and construct a zero-emission advanced nuclear power plant in Upstate New York.  The plant is to produce 1 GW of power, about half of what the decommissioned Indian Point Power Plant produced when it provided significant amounts of power to New York City residents.

Renewed interest in nuclear power has emerged in part because of the soaring electricity demand from AI data centers.  Companies like Amazon, Google, and Microsoft have all begun investing in nuclear power for this reason.

NYPA is instructed to begin evaluating technologies, business models, and locations for the new power plant and will seek to secure key partnerships needed for the project.  As things stand, it is not known what technology the plant will use, where in Upstate New York it will be located, how much it will cost to build, who will pay for it, and how long it will take to build. 

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New York Again Embraces Nuclear Power With Plans to Build New Plant

Photo courtesy of Constellation Energy.

Earth Wise is a production of WAMC Northeast Public Radio

Sun powered carbon capture

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As the world struggles to implement technologies and find the political will to reduce carbon emissions, there are also ongoing efforts to find ways to capture carbon from emitting sources and from the atmosphere itself.  After capturing carbon dioxide, there is then the need to safely store it or make use of it.

Current methods for capturing and then releasing carbon dioxide are expensive and energy intensive.  In fact, some methods even require the use of fossil fuels.  Recently, researchers at Cornell University have developed a method for capturing carbon dioxide that is powered by sunlight.

The Cornell method mimics the mechanisms that plants use to store carbon which involves using sunlight to make a reactive enol molecule that grabs carbon dioxide.  

Existing chemical-based carbon capture techniques make use of amines, which are organic ammonia-derived compounds that react selectively with carbon dioxide.  But amines are not stable in the presence of oxygen and don’t last, which necessitates the energy-intensive production of more and more amines.

The Cornell method uses the same method that the plant enzyme RuBisCo uses in photosynthesis.  It is based on an inexpensive sorbent material that is capable of a high rate of carbon capture.

The researchers tested the system using flue samples from Cornell’s Combined Heat and Power Building, an on-campus power plant that burns natural gas.  The system was successful in isolating carbon dioxide.

Ultimately, they would like to stage the reaction on what looks like a solar panel, but one that would capture carbon instead of generating electricity.

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In a first, system uses sunlight to power carbon capture

Photo, posted August 8, 2015, courtesy of Holly Victoria Norval via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Fuel from Corn Waste

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A substantial amount of corn is grown in this country for the purpose of producing ethanol.  The value of doing so is debatable for many reasons.  Nevertheless, the majority of the corn crop is grown for food.  But along with all that corn, there is corn stover.  Stover is the dried stalks, leaves, and other plant parts that remain in the field after the corn itself has been harvested.  Corn stover is the largest quantity of biomass residue in the United States.  Around 250 million tons of it is produced annually and the majority of it is left unused.  Some is used for animal feed and other purposes and has monetary value, but much of it goes to waste.

Scientists at Washington State University have developed a way to produce low-cost sugar from stover that can be used to make biofuels and other bioproducts.

Corn stover is an abundant and cheap source of biomass, which holds great potential as a source of energy and valuable chemicals.  The challenge is to overcome the high cost of processing stover whose complex structural molecules like cellulose and lignin need to be broken down.

The new process uses potassium hydroxide and ammonium sulfite to convert stover into a sugar.  It is a mild-temperature process that allows enzymes to break down the cellulosic polymers in stover into sugar, which can then be fermented into biofuels.  The resulting sugar from the process would be cost-competitive with low-cost imported sugars. The researchers estimate that their patent-pending process could produce sugar that could be sold for as low as 28 cents per pound.

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Scientists discover a new way to convert corn waste into low-cost sugar for biofuel

Photo, posted August 30, 2012, courtesy of Idaho National Laboratory Bioenergy Program via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking emissions by satellite

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Carbon dioxide and nitrogen oxides are two of the most problematic human-generated air pollutants that negatively impact air quality, the climate, and human health.  Satellites are an important tool for monitoring emissions of these pollutants, but they have limitations.  For the most part, satellites have limited spatial resolution, meaning that they can’t reliably narrow down the source of emissions sufficiently to pin down a specific location such as a power plant. 

Until now, there have been no instruments that can detect both carbon dioxide and nitrogen oxide simultaneously with high spatial resolution.  Often just nitrogen oxide measurements are made, and carbon dioxide levels estimated based on the fact that both are emitted together with typical ratios.

A German research team from the Max Planck Institute and the Heidelberg Institute have developed a technology for the EnMAP environmental satellite to detect both gases with an unprecedented spatial resolution of 30 meters.  Data from the satellite makes it possible to track multiple sources of emission plumes over several tens of kilometers.

The EnMAP system was originally designed for remote sensing of land surfaces.  The new research demonstrates that reliable measurements of trace gases are possible even with an instrument not specifically designed for atmospheric observations.  When using it, it’s possible to determine the distribution of carbon dioxide and nitrogen oxide in emission plumes from individual power plants.  The ability to measure both gases individually means that conclusions can be drawn about the technology, efficiency, and operating mode of the systems being measured.

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German satellite measures CO2 and NO2 simultaneously from power plant emissions for the first time

Photo, posted September 19, 2020, courtesy of Sandor Somkuti 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

Empire Wind resumes

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In April, the Trump Administration issued a stop order for the Empire Wind offshore wind project in New York, pushing the $5 billion project to the brink of collapse.  The project is being built by the giant Norwegian energy company Equinor.  When completed, the wind farm is expected to deliver enough electricity to power 500,000 New York homes.

Equinor had obtained all the necessary permits for the project after a four-year federal environmental review and work had begun on laying foundations for the wind turbines on the ocean floor. 

Interior Secretary Doug Burgum claimed that the permits for the project been rushed and ordered the work stopped.  The stoppage was costing Equinor $50 million a week as well as jeopardizing an additional 1,000 jobs. 

Weeks of intensive interactions between New York Governor Kathy Hochul, Equinor officials, and the White House finally resulted in a decision by the administration to lift the stop work order and allow the project to move forward. 

The collapse of the project would have created major problems for New York.  The state’s grid operators have been counting on the construction of several new offshore wind farms to provide large additional amounts of electricity without producing greenhouse gas emissions.  New York has aggressive targets for using renewable energy.

Empire Wind is expected to have 816 megawatts of capacity.  Another offshore project in New York, Sunrise Wind, which is under construction 30 miles east of Montauk Point on Long Island, would have 924 megawatts of capacity.

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In Reversal, Trump Officials Will Allow Huge Offshore N.Y. Wind Farm to Proceed

Photo, posted August 9, 2022, courtesy of the Scottish Government via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Five amazing renewable energy projects

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Worldwide investment in renewable energy topped $2 trillion in 2024.  For Climate Solutions Week, we wanted to highlight some amazing projects around the world that showcase innovative technology, ambitious scale, and the commitment to a cleaner and sustainable future.

In Morocco, the Noor Solar Power Station is a huge concentrated solar power facility that generates power for more than a million Moroccans.  The facility stores some of the heat generated by the sun in molten salt so it can continue to produce power after sunset.

The Three Gorges Dam in China is the world’s largest power plant by installed capacity.  The 32 turbines generate enough electricity to power millions of homes. 

The Alta Wind Energy Center in California is one of the largest onshore wind farms in the world.  The 600 turbines at the facility provide clean electricity for up to 450,000 homes.

The Yamakura Dam Floating Solar Project in Japan has more than 50,000 solar panels that provide electricity for about 5,000 households.  The plant is located atop the surface of the Yamakura Dam reservoir and is one of the largest floating solar installations in the world.

The Hellisheiði Power Station in Iceland is one of the world’s most technologically advanced geothermal energy plants.  It taps into Iceland’s volcanic geology and draws both high-pressure steam and hot water to provide both electricity and heat to thousands of local homes and businesses.  

These five projects are just a sampling of the renewable energy development going on all over the world.

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Powering the Future: Innovative Renewable Energy Projects Around the World

Photo, posted December 1, 2019, courtesy of Richard Allaway via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Solar on farmland

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New studies have found that devoting a small percentage of U.S. farmland to producing solar power would benefit both the country’s energy system and its farmers.

Currently, about 46,000 square miles of farmland – about the area of Pennsylvania – is being used to grow corn to make ethanol.  One study looked at the impact of using some of this land for solar power instead of corn ethanol.

Not much of all this farmland is close enough to electrical transmission lines to be practical for utility solar power.  In fact, only about 1,500 square miles fits the bill.  But if even this small fraction of the corn growing land was used instead for solar power, it would generate as much energy each year than from all of the farms growing corn for fuel.

Solar installations on farms are helpful for farmers as well.  The land beneath the panels can be used to grow wildflowers that attracts the bees, wasps, and other insects needed to pollinate crops in the nearby fields.  In addition, the solar arrays provide a steady income stream for farmers.

In some places, farmers can earn substantially more from leasing their land for solar than from growing crops.  But a study of farms in California suggests that the best option is to do both.  Farmers who both grow crops and host solar arrays can have more financial security than those who do just one or the other.  The income from solar arrays is pretty predictable and is paid throughout the year.  Income from crops can drop off from, for example, a seasonal drought, or from extreme weather events.

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To Help Growers and the Grid, Build Solar on Farmland, Research Says

Photo, posted June 9, 2016, courtesy of Matt Lavin via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Saharan dust and solar power

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The world is a big place but even things that are far away can have serious local consequences.  The effects of distant Canadian wildfires on air quality in Florida is a good example.

Europe is increasingly becoming reliant on solar energy to meet its targets for climate change mitigation and energy security.   According to new research by four Hungarian universities, mineral dust carried on the wind from the Sahara Desert is not only reducing electricity generation from solar power across Europe but it is also making it harder to predict what gets generated.

The Sahara releases billions of tons of fine dust into the atmosphere each year.  Tens of millions of tons reach European skies where the tiny particles scatter and absorb sunlight, reduce the amount of light reaching the surface, and even promote cloud formation.   All of these things reduce the output of photovoltaic systems.

In addition, conventional weather forecasting tools don’t consider the effects of Saharan dust events, so that scheduling of solar power for the energy system becomes less reliable.  Incorporating these events into new forecast models will be essential.

Apart from the atmospheric effects of the dust, there are also long-term impacts due to dust contaminating and eroding the physical infrastructure of solar panels thereby further reducing their efficiency and increasing maintenance costs.

Over time, south-to-north transport of Saharan dust is likely to become more pronounced due to a steeper thermal gradient.  Currently, the quantities of atmospheric dust, the dynamics of its transport, and the physical properties of the dust itself are not very well understood.  Understanding these things will be crucial for Europe’s energy future.

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The shadow of the wind: photovoltaic power generation under Europe’s dusty skies

Photo, posted March 11, 2023, courtesy of Mark Wordy via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A giant plane for giant wind turbines

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Wind turbines have been getting bigger all the time.  Larger turbines have real advantages.  They can operate at lower speeds so they can be deployed in more places.  They capture more wind, so they make more power.  Large wind turbines can have blades more than 200 feet long and even larger ones are on the way.  An offshore wind farm in China has turbines with 400-foot blades.

Giant wind turbines face a thorny problem:  getting the blades to where they are to be installed.  The enormous blades can’t be easily shipped across aging roads and bridges.   Tunnels are too narrow, bridges are too low, and roads can be too tight to allow turns when transporting these massive turbine parts.  Some developers have actually had to build special roads for wind projects.

For nearly a decade, a Boulder Colorado company called Radia has been working on what would be the world’s largest plane.  The WindRunner aircraft would have a dozen times the cargo volume of a Boeing 747.  The WindRunner will be 356 feet long and 79 feet tall.  While its primary purpose would be transporting wind turbine blades, the plane could also be used to aid the military or businesses that are thinking really big.  Product developers often don’t even try to invent really big things because there is no way to transport them.  Radia expects the WindRunner to be rolled out before the end of the decade.

The wind industry is currently facing strong opposition from the Trump administration, but wind energy is not going away and bigger and better wind turbines will ultimately be built and will have to be transported.

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Building the World’s Biggest Plane to Help Catch the Wind

Photo, October 10, 2013, courtesy of Allan Der via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

More eco-friendly desalination

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There are about 16,000 operational desalination plants, located across 177 countries, which generate an estimated 25 billion gallons of fresh water daily.

For every gallon of drinking water produced at a typical desalination plant, one and a half gallons of brine are produced.  Much of it is stored in ponds until the water evaporates, leaving behind solid salt or concentrated brine for further treatment.  There are various other techniques for concentrating brines, but they are energy-intensive and environmentally problematic.  The process called electrodialysis uses electrified membranes to concentrate salts. 

Water flows into many channels separated by membranes, each of which has the opposite electrical charge of its neighbors.  Positive salt ions move towards negatively charged electrodes and negative ions move toward positive electrodes.  Two streams result, one containing purified water and one containing concentrated brine.

This eliminates the need for evaporation ponds, but existing electrodialysis membranes either result in leakage of salts into the environment or are too slow, making the process impractical for large-scale use.

Researchers at the University of Michigan have developed a new kind of membrane for electrodialysis.  The new membranes don’t leak and are ten times more conductive than those on the market today which means that they can move more salt using less power.  The membranes can be customized to suit a broad range of water types, which may help make desalination a more sustainable solution to the world’s growing water crisis.

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Making desalination more eco-friendly: New membranes could help eliminate brine waste

Photo, posted February 4, 2012, courtesy of David Martinez Vicente via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Hot water in Boise

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Boise is the capital of Idaho, and the Idaho Statehouse is the only one in the United States to use geothermal heat.  Geothermal heating is possible in Boise because of fault lines that expose its groundwater to hot rocks.  The underground water supply in Boise is heated to around 170 degrees Fahrenheit.  It is the basis of the largest municipally-run geothermal system in the country.

People in Boise began using this natural resource to supply heat to buildings in the 1890s by drilling wells into aquifers that yielded hundreds of thousands of gallons of piping hot water a day.  The water heated pools and public baths, a Victorian mansion, and, eventually, hundreds of homes in what was called the Boise Warm Springs Water District.

The number of buildings that the city of Boise heats with its geothermal resource has grown more than sixfold over the past 40 years.  The water is drawn from wells in the nearby foothills and pumped into a closed-loop network of pipes that reach into buildings.  In each building, the geothermal heat is transferred to water in separate adjoining pipes that distribute the heat throughout the building.  The well water goes back to the aquifer to be heated again.

Today, there are four separately run geothermal water systems in Boise.  One is run by the city, another by the Boise Warm Springs District, and two others that serve the Capitol and Veterans Affairs Buildings.

In 2024, city officials calculated that using geothermal heat reduced annual carbon dioxide emissions by 7,000 tons, the equivalent of removing 1,500 gas-powered cars from the road each year.

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They’re in Hot Water in Idaho. Here’s Why That’s a Good Thing.

Photo, posted May 26, 2010, courtesy of Jason W via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Electric trains are healthier

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The majority of commuter trains in the U.S. are powered by diesel fuel.  This is despite the fact that electric trains are quieter, more reliable, and produce fewer greenhouse gases than diesel locomotives.  A new study has found that electric trains are healthier for passengers as well.

Caltrain carries millions of passengers a year along a 47-mile route between San Francisco and San Jose.  It is the busiest commuter rail system in the western U.S.  Over a six-week period beginning in August 2024, Caltrain retired all 29 of its diesel locomotives and replaced them with electric trains.

As the process began, an environmental engineering and environmental health professor at UC Berkeley noticed the rapid change in the air aboard the trains and decided to study its potential health impacts.  With the support of Caltrain, he installed black carbon detectors aboard the trains and tracked the improvements in air quality as old diesel locomotives were being replaced by new electric trains.

Statistical analysis of the reduction in black carbon exposure achieved by the change predicted a reduction in excess cancer deaths by 51 per million people for passengers and 330 per million people for train conductors.  EPA policy states that any exposure that increases the average individual’s cancer risk by more than one per million is considered unacceptable.

In the context of the whole U.S. where millions of people commute by rail every day, the study predicts that hundreds of cases of cancer could be prevented each year.  California has long-term plans to electrify most of its rail systems.  The study indicates that the process shouldn’t be carried over the next 25 years but rather be sped up.

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Electric trains are quieter, more reliable than diesel. New study finds they’re healthier, too.

Photo, posted September 4, 2024, courtesy of J. Kehoe via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Scrubbers to clean up shipping

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Cargo ships are significant sources of global air pollution because of their fuel oil.  Most ships burn heavy fuel oil that is loaded with sulfur, so when it is burned it produces noxious gases and fine particles that can harm human health and the environment.  The International Maritime Organization enacted a mandatory cap of 0.5% for the sulfur content of marine fuels in 2020.  Heavy fuel oil has a sulfur content of 2 to 3 percent.

Shipping companies can comply by burning low-sulfur fossil fuels or biofuels, but these are much more expensive.  The most feasible and cost-effective option is to install exhaust gas cleaning systems, known as scrubbers. 

A scrubber is a huge metal tank installed in a ship’s exhaust stack.  Seawater is sprayed from nozzles to wash the hot exhaust.  The seawater reacts with sulfur dioxide and converts it to sulfates, which are environmentally benign natural components in seawater.

A study by the National Technical University of Athens in Greece has performed a lifecycle assessment of the use of scrubbers and has found that burning heavy fuel oil with the use of scrubbers can match or even surpass the benefits of using low-sulfur fuels.

Producing low-sulfur fuel causes additional greenhouse gas and particulate matter emissions in refineries. On the other hand, scrubbers reduce sulfur dioxide emissions by 97% and dramatically reduce other pollutants as well.

The study shows the importance of incorporating lifecycle assessments into evaluation of environmental impact reduction policies.

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Study: Burning heavy fuel oil with scrubbers is the best available option for bulk maritime shipping

Photo, posted August 3, 2015, courtesy of Lotsemann via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Renewables dominate new global power

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The current administration in the United States is adversarial towards renewable energy and highly supportive of the use of fossil fuels.  Unquestionably, this will create rough waters for the clean energy industry and, unfortunately, will throw a monkey wrench into the world’s efforts to mitigate climate change.  But it cannot stop what has become a powerful global trend.

In the words of U.N. Secretary-General António Guterres: “Renewable energy is powering down the fossil fuel age.”

According to a new report from the International Renewable Energy Agency, renewables accounted for 92% of new power capacity worldwide last year.  Solar is by far the fastest-growing form of renewable power, accounting for 77% of new capacity.

In the U.S., renewables accounted for about 90% of new installed capacity in 2024.  The country added nearly 40 GW of solar power capacity as well as 5 GW of wind power.  Renewables now make up about 30% of the country’s large-scale power generating capacity.  Adding in all carbon-free electricity sources (which include nuclear power), nearly 44% of the country’s electricity was carbon-free.

Headwinds against the growth of renewable energy are getting stronger in the US, but the global trend driven by both economics and environmental concerns is powerful and will continue.  For one thing, in much of the world, solar power is simply the cheapest way to produce electricity and that is pretty difficult to ignore. Global trade wars and economic turmoil will impact renewable energy much as they will other industries, but the long-term trend is clear.

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Renewables Made Up More Than 90 Percent of New Power Installed Globally Last Year

Photo, posted November 23, 2022, courtesy of John Morton via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The cost of electric vehicle batteries

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The battery pack in an electric car is the most expensive part of the car. Currently, it accounts for as much as 30% of the price.  But EV batteries last a long time.  Most are guaranteed for 8-10 years and are likely to last as long as 20 years.  In practice, only 1.5% of electric cars need battery replacements for one reason or another.

The economics of EV batteries has changed dramatically over time and will continue to do so.  EV battery capacity is measured in kWh, the units you are charged for your home electricity.  An EV with a 300-mile driving range will have a battery pack that holds something like 75 kWh.

In 2008, when electric cars were just starting to enter the market again after earlier false starts, lithium-ion battery packs cost $1,355 per kWh.  When the Tesla Model S was introduced in 2012, packs were about $800. By 2019, packs broke the $200 per kWh barrier. Last year, lithium-ion battery packs reached $115 per kWh.

A combination of technology improvements and strong market competition with growing supplies is driving prices ever lower.  Industry analysts expect battery prices to drop well below $100 this year and reach about $80 next year.

The result of all of this cost reduction is that EVs will be cheaper than equivalent internal combustion vehicles, which in fact is already the case in China. Apart from cost, batteries for cars continue to improve so that the driving range of EVs will continue to increase making the cars more attractive and very practical for nearly all drivers.

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How Much Do Electric Car Batteries Cost to Replace?

Photo, posted January 22, 2019, courtesy of Steve Rainwater via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Grid reliability and grid-edge resources

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A new study by MIT researchers looked at the potential for grid-edge resources to enhance the ability of the electric grid to respond to unforeseen power outages.  Grid-edge resources are devices found close to consumers rather than located near central power plants, substations, or transmission lines.  These include residential solar panels, storage batteries, electric vehicles, heat pumps, smart thermostats and smart water heaters.

These grid-edge devices can independently generate, store, or tune their consumption of power and increasingly, they are online internet-of-things devices.  The MIT study outlined a blueprint for how such devices could reinforce the power grid through a local electricity market.  Owners of grid-edge devices could subscribe to such a market and essentially loan out their device as part of a microgrid or local network as on-call energy resources.

Electric vehicles could provide power rather than consuming it when necessary.  Storage batteries could do the same.  Devices like smart dishwashers and thermostats would reduce their power demands when necessary.

In the event that the main power grid is compromised, an algorithm would determine which grid-edge devices were available and trustworthy and would either use them to pump power into the grid or reduce the power they are drawing from it in order to help mitigate the power failure. 

The MIT researchers illustrated this grid resilience strategy through a number of grid attack scenarios including failures from cyber-attacks and natural disasters.   Their analysis showed that various networks of grid-edge devices are capable of defeating various types of grid failures.

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Rooftop panels, EV chargers, and smart thermostats could chip in to boost power grid resilience

Photo, posted October 10, 2019, courtesy of Noya Fields via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Recycling lithium-ion batteries

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Lithium-ion batteries are used to power computers and cellphones and, increasingly, vehicles.  The batteries contain lithium as well as various other valuable metals such as nickel, cobalt, copper, and manganese.  Like other batteries, lithium-ion batteries have a finite lifetime before they can no longer perform their intended function.

Recycling lithium-ion batteries to recover their critical metals is an alternative to mining those metals.  A recent study by Stanford University analyzed the environmental impact of obtaining those metals using lithium-ion battery recycling compared with mining.  They found that the recycling process is associated with less than half of the greenhouse gas emissions of conventional mining.  The process uses about one-fourth of the water and energy of mining new metals.  North America’s largest industrial-scale lithium-ion battery recycling facility is Redwood Materials, located in Nevada, which uses a clean energy mix that includes hydropower, geothermal, and solar power.

These calculated advantages are associated with recycling batteries that have been in use.  The advantages are even greater for recycling scrap:  defective material from battery manufacturers.

The advantages of recycling are dependent on the sources of electricity at the recycling plant and the availability of fresh water. 

At present, the U.S. recycles about half of its available lithium-ion batteries.  By comparison, 99% of lead-acid batteries (like those found in cars and trucks) have been recycled for decades.  As the supply of used lithium-ion batteries continues to increase, it is important for the availability of industrial-scale battery recycling to keep pace. 

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Recycling lithium-ion batteries delivers significant environmental benefits

Photo, posted May 7, 2020, courtesy of Mark Vletter via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The green grab for land

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Solar and wind farms are spreading rapidly around the world.  Many economists believe that solar power has crossed the threshold where it is generally cheaper than other ways to make electricity and will become the dominant energy source in the next couple of decades.  As a result, both solar and wind farms are gobbling up more and more land around the world.  Estimates are that they will take up around 30,000 square miles by mid-century.

One concern is whether we are entering an era of trading food for energy.  Land conflicts seem inevitable since solar power operates best in unshaded areas with gentle winds and moderate temperatures, which are the same conditions favored by many crops.

China is installing more solar farms than the rest of the world combined.  Many of these are in the Gobi Desert, where there is no competing need for the land.  But some are in eastern China, in densely populated grain-growing areas.

There are a number of strategies that reduce the impact of solar farms on land use.  One approach is to put them on old industrial or brownfield sites that are otherwise unusable.  Another is floatovoltaics:  putting solar panels on the surface of lakes and reservoirs.  And then there is agrivoltaics, where solar panels are installed above crop fields or where livestock graze between or even beneath solar arrays.  China has more than 500 agrivoltaic projects that incorporate crops, livestock, aquafarming, greenhouses, and even tea plantations.

Green energy has both environmental and economic benefits to offer, but it must conserve nature and not excessively grab land needed for people, wildlife, and ecosystems.

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‘Green Grab’: Solar and Wind Boom Sparks Conflicts on Land Use

Photo, posted May 25, 2011, courtesy of Michael Mees via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Are today’s refrigerants safe?

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Refrigeration is based on heat transfer mediums that absorb heat from the area being cooled and transfer it to the outside environment.

The earliest refrigerants were dangerous substances like ammonia.  In the 1930s, chlorofluorocarbons (CFCs) like Freon became the standard refrigerant for use in refrigeration systems and even in aerosol cans.  When these substances were found to be depleting the earth’s ozone layer, the Montreal Protocol dictated their phaseout and by the mid-1990s, CFCs were largely replaced by hydrofluorocarbons (HFCs).

HFCs don’t deplete the ozone layer, but they were eventually determined to be potent greenhouse gases, thousands of times more planet-warming than carbon dioxide.   As a result, the global phaseout of HFCs began in 2016, and have been increasingly replaced by hydrofluoroolefins (HFOs), which are considered a more environmentally-friendly alternative to all their predecessors.

Trying to not be surprised by additional unpleasant discoveries about refrigerants, researchers are studying the potential environmental impacts of HFOs.  Researchers at the University of New South Wales in Australia have found that HFOs can break down in the atmosphere and that some small amounts of the resultant products are in fact fluoroforms, which are the HFC with the greatest global warming potential and can stay in the atmosphere for up to 200 years.

That only a small amount of HFC gets into the atmosphere is good, but nevertheless it reveals that the consequences of replacing widely-used chemicals are not a simple matter to determine.

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Are our refrigerants safe? The lingering questions about the chemicals keeping us cool

Photo, posted July 19, 2021, courtesy of Vernon Air Conditioning via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

WAMC Northeast Public Radio

WAMC/Northeast Public Radio is a regional public radio network serving parts of seven northeastern states (more...)