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Battery life in electric cars

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Most of us have lots of experience with the batteries in phones, computers, and other gadgets.  Batteries don’t last forever, and we sometimes have to replace them.  It’s a fact of life.   These days, it’s becoming more common to drive electric cars and the fundamental principle is the same.  However, the battery pack in an EV is the most expensive part of the car, so its reliability and lifespan is a greater concern.

EV batteries generally have generous warranties.  In the US, EV batteries are required by federal law to be covered for at least 8 years or 100,000 miles, whichever comes first.  So, the financial exposure from the battery pack is reasonably limited.  Even so, EV owners would like to know that their car’s battery pack is likely to last a long time.

Battery life is generally determined by laboratory tests involving repeated charge-discharge cycles over a relatively short period of time, as opposed to those cycles being spaced out over years.

A new study by Stanford University looked at battery performance under conditions much more like what would be experienced in the real world.  Cars experience frequent acceleration, braking that charges the batteries a bit, lots of stops, periods of rest, and so forth.  Nothing like just charging and discharging repeatedly.

The study found that today’s EV batteries may last up to 40% longer than expected.  Real-world stop-and-go driving benefits batteries more than standard test conditions.

The cost of EV batteries continues to get lower all the time and it is likely to be quite a long time before one is likely to need a new battery assuming one even keeps the car long enough.

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Existing EV batteries may last up to 40% longer than expected

Photo, posted August 27, 2021, courtesy of Ron Frazier via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The carbon cost of wind farms

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Opponents of electric vehicles and renewable energy often try to make arguments to the effect that the carbon footprint associated with producing electric cars, solar panels, and wind turbines negates their advantages over legacy technologies that involve burning fossil fuels.  These arguments have been soundly refuted for the case of electric vehicles but there have been fewer studies related to other green technologies.

A new peer-reviewed study by engineers at the Te Herenga Waka Victoria University in Wellington, New Zealand, has analyzed the carbon emissions associated with wind farm operation.

The main result is that after operating for less than two years, a wind farm can offset the carbon emissions generated across its entire 30-year lifespan.   The study takes into account everything from the manufacturing of individual turbine parts, to transporting them and installing them into place, to decommissioning the entire wind farm at its life’s end.  The environmental impacts of the installation and transportation phases are important, accounting for about 10% of the overall emissions.

The decommissioning phase is also important.  The study recommended the development of a recycling process for end-of-life turbine blades.  Currently, such blades are disposed of in landfills, but a recycling process could reduce emissions.

The manufacturing of wind turbines is the primary contributor to the carbon and energy consumption footprints and continues to be the subject of efforts to be improved.

There are other aspects of wind farms that are subject to criticism including physical impacts on the local environment and various social, wildlife and economic impacts.  But with respect to carbon emissions, wind farms are a winning strategy.

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Wind Farms can Offset Their Emissions Within Two Years, New Study Shows

Photo, posted April 2, 2017, courtesy of Ian Dick via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Small changes can yield big results

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Global food production is one of the largest contributors to climate change.  In fact, one-quarter of the world’s greenhouse gas emissions result from food production and agriculture.  Be that as it may, we still have to eat.  But what we choose to eat has a major impact on the environment.

According to a new study by researchers at McGill University in Canada and the London School of Hygiene & Tropical Medicine in the U.K., partially replacing red and processed meat with plant-based proteins can increase lifespan and mitigate climate change. 

In the study, which was recently published in the journal Nature Food, the researchers drew data from a national nutrition survey to analyze Canadians’ dietary records. The study modeled partial replacements (25% and 50%) of either red and processed meat or dairy with plant protein foods like nuts, seeds, legumes, and tofu, on a combination of nutrition, health, and climate outcomes.

In the study, the researchers found that a person’s diet-related carbon footprint plummets by 25% when they replace half of their intake of red and processed meats with plant protein foods. However, dairy substitutions showed smaller reductions of up to just 5%.

Meat and dairy-rich diets are known to increase the risk of heart disease, diabetes, and certain cancers. The researchers also estimated that if half of the red and processed meat in a person’s diet was replaced with plant protein foods, life expectancy would increase nearly nine months on average, due to a reduced risk of chronic disease.

The research team hopes its findings will help people make healthier and more sustainable food choices. 

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Food production is responsible for one-quarter of the world’s greenhouse gas emissions

Small dietary changes can cut your carbon footprint by 25%

Photo, posted November 24, 2019, courtesy of Theo Crazzolara via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Infinitely Recyclable Plastic | Earth Wise

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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.

WAMC Northeast Public Radio

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