replacement

Transparent wood

April 25, 2025 By EarthWise Leave a Comment

Plastics are pretty much everywhere in the modern world including places we want them to be and places where we don’t. Conventional plastics are not biodegradable and instead cause increasing problems wherever they end up after their useful life. As a result, there are global efforts to find environmentally friendly replacements for petroleum-based plastics.

An interesting candidate for replacing many types of plastic is transparent wood. Transparent wood is a man-made material derived from natural wood. Wood has three components: cellulose, hemicellulose, and lignin. Transparent wood is created by removing the lignin and hemicellulose, leaving behind a porous, paper-like network of cellulose. It is transparent but lacks structural strength. In the past, clear materials like epoxies have been added to produce a strong, transparent material: transparent wood. But because of the epoxy – itself a form of plastic – the resultant material was non-biodegradable.

Researchers at Kennesaw State University in Georgia have developed a method for producing transparent wood that replaces epoxies with an egg white and rice extract mixture along with a curing agent called diethylenetriamine. The end product is a semi-transparent form of wood that is biodegradable.

The researchers also incorporated silver nanowires into samples of their transparent wood. This enabled the wood to conduct electricity and could be useful in wearable sensors or as coatings for solar cells. There is additional research needed to improve the properties of this transparent wood, but a plastic replacement made from natural and inexpensive materials could be quite valuable.

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Making sturdy, semi-transparent wood with cheap, natural materials

Photo, posted August 1, 2017, courtesy of NOAA Marine Debris via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The cost of electric vehicle batteries

April 4, 2025 By EarthWise Leave a Comment

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

Biodegradable microplastics

April 10, 2024 By EarthWise Leave a Comment

Ordinary plastics are not biodegradable, but they are also not indestructible. Plastics in the environment can break down into tiny fragments – microplastics – and those, unfortunately, are nearly indestructible. Microplastics have been documented in the oceans and in soil virtually everywhere on Earth including remote frozen wastelands and on top of high mountains. More recently, they have been found in our own arteries, lungs, and even in placentas. Microplastic pollution is a very serious problem.

There is considerable ongoing effort to develop biodegradable plastics from non-petroleum sources. There has been progress but it has not necessarily been aimed at creating bioplastics that do not create microplastic when they break down.

Researchers at the University of California San Diego have developed algae-based polymers that they have shown to degrade when composted. Recently, in work published in the journal Nature Scientific Reports, they have shown that even fine microparticles of their bioplastic are digested by microbes when placed in a compost. What remains are the starting plant materials from which the plastic was made. Products made from this sort of plastic would not only be sustainable beyond their useful lifetime but would also not represent a potential danger to human life.

Creating this eco-friendly alternative to petroleum-based plastic is only the first step toward creating a viable replacement for existing plastics. It is necessary to be able to use the new material on existing manufacturing equipment and for it to have the same mechanical and thermal properties as the materials it is replacing. But the researchers are optimistic that this could be a potential solution to an increasingly serious problem.

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Say Hello to Biodegradable Microplastics

Photo, posted January 17, 2018, courtesy of Bo Eide via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Primary Ways To Mitigate Climate Change | Earth Wise

May 30, 2022 By EarthWise Leave a Comment

The most recent report issued by the Intergovernmental Panel on Climate Change states that the world must halt the increase in greenhouse gases within three years, reduce emissions by 43% in the next seven years, and eliminate them entirely by 2050. Otherwise, there will likely be catastrophic and irreversible impacts on the climate.

With respect to achieving these reductions, the report emphasizes decarbonizing the energy sector through electrification by replacing fossil fuels anywhere and everywhere possible. Where that isn’t yet practical – such as in shipping and aviation – the use of biofuels and hydrogen can provide a stopgap until battery technology becomes a viable alternative.

The economics of this approach continue to improve. Since 2010, the cost of wind, solar, and batteries has declined by as much as 85%. In many cases, costs have fallen below those of fossil fuels. Nonetheless, the report stresses that continuing to provide national, state, and local incentives for using renewable energy is a key factor in achieving the necessary reductions.

However, reducing emissions will no longer be enough. This is the first major IPCC report that states that man-made carbon dioxide removal strategies will be necessary to meet the goals of the Paris Climate Agreement. So-called natural carbon storage options, like planting trees and using farming methods that sequester carbon in soil, are also important parts of the strategy.

It is up to governments, policymakers, and investors to implement the necessary changes to mitigate climate change. There is lots of talk about it, but it will take concerted action to avoid increasingly dire consequences.

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Report highlights affordable, available ways to mitigate climate change now

Photo, posted September 8, 2007, courtesy of Kevin Dooley via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Second Life For Electric Car Batteries | Earth Wise

June 17, 2020 By EarthWise Leave a Comment

The number of electric cars around the world is growing steadily. Battery technology continues to improve and the battery packs in the cars can have a long life. Generally, the batteries are considered to require replacement only when their range has dropped below 80% of its original value. Many are warranted to last for 8 to 10 years or more than 100,000 miles. Some seem to do much better than that.

But however long it takes, there will eventually be a wave of used batteries whose performance is no longer deemed sufficient for vehicle use. A new study, published in the journal Applied Energy, looked at the application of used vehicle batteries as backup storage for grid-scale solar photovoltaic installations where they could perform for more than a decade in this less demanding role.

The study looked at the economics of several scenarios including running a solar farm with no battery back up, running the same farm with brand-new batteries, and running the farm with a battery array made of repurposed vehicle batteries.

They found that the used EV battery array, if managed properly, could be a good, profitable investment provided that the batteries cost less than 60% of their original price. They looked at the technical issues of screening batteries and combining batteries from different cars to work together. They also looked at the economics of removing batteries from cars, collecting them, checking them over, and repackaging them.

Overall, they found that reusing vehicle batteries could ultimately meet half the forecasted demand for renewable energy backup storage over the next 10 years and would be both a technical and an economic success story.

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Solar energy farms could offer second life for electric vehicle batteries

Photo, posted June 10, 2011, courtesy of Nick Ares via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Biodegradable Microbeads

July 20, 2017 By EarthWise

Microbeads are little spheres of plastic less than half a millimeter in diameter that are added to a variety of personal care and cleaning products such as cosmetics, sunscreens and fillers. They give these products a desirable smooth texture. However, they are so small that sewage filtration systems can’t remove them and they end up in rivers and oceans where they are ingested by birds, fish and other marine life.

Climate-Friendly Refrigerants

March 29, 2017 By EarthWise

In 1988, President Reagan signed the Montreal Protocol, which banned CFC refrigerants like Freon in air conditioners and refrigerators. The chlorofluorocarbons were the cause of a giant hole in the ozone layer, which has been shrinking ever since the ban. Unfortunately, the chemicals that replaced CFCs – hydrofluorocarbons or HFCs – have their own major problem: they are a seriously bad greenhouse gas, far worse than carbon dioxide. Last fall, an international agreement was reached by over 170 countries to reduce and eventually replace HFCs, which included 100 developing countries like China and India where air conditioning use is growing fastest.