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Plant-Based Foods And CO2 Emissions | Earth Wise

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We often hear how eating locally-sourced food is a way to minimize the carbon footprint of our diet.  But from a climate impact perspective, this only has a significant impact if transportation is responsible for a large portion of a food’s final carbon footprint.  In many cases, the greenhouse gas emissions related to transportation make up only a small portion of the total emissions from food, and what we eat is far more important.

In general, beef and lamb have the biggest climate footprint per gram of protein.  Plant-based foods tend to have the smallest impact. Pork and chicken are somewhere in the middle. 

According to new research, U.S. food production could reduce its agricultural carbon footprint between 2.5% and 13.5% by embracing plant-based alternatives to beef.  The study, from researchers at Cornell University, Johns Hopkins University, and international partners, found that most of the reduction would be achieved by decreasing the number of cows needed for beef production by two to twelve million animals.  The research was recently published in the journal Lancet Planetary Health.

However, the researchers also found that acting to reduce climate change in this manner could have unintended consequences.  For example, economic models from the research team show that the growth in popularity of plant-based beef could disrupt the agricultural workforce, threatening more than 1.5 million jobs. 

But in the big picture, doing nothing will cost much more than doing something to slow climate change.  Shifting diets away from meat and other animal products and towards more plant-based foods will help shrink carbon footprints and mitigate climate change.  It’s a win-win for the planet and for human health. 

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Plant-based ‘beef’ reduces CO2 but threatens ag jobs

Photo, posted November 27, 2018, courtesy of Sarah Stierch via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Wireless EV Charging | Earth Wise

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Michigan, historically the focus of the American auto industry, has announced a new initiative to develop the nation’s first wireless charging infrastructure on a public road.  The Inductive Vehicle Charging Pilot is a partnership between the Michigan Department of Transportation and the Office of Future Mobility and Electrification.

The idea is to deploy an electrified roadway system that allows electric buses, shuttles, and vehicles to charge while driving, allowing them to operate continuously without stopping to charge.  In principle, such electrified roadways have the potential to accelerate the adoption of electric vehicles and turn public streets into safe and sustainable shared energy platforms.  This is especially valuable for drivers who might not have easy access to conventional charging facilities.

The pilot program is seeking proposals to design, fund, evaluate, iterate, test, and implement an inductive charging system along a one-mile stretch of state-operated roadway in Michigan.

The basic concept is to embed coils in a road that will convey electricity to cars outfitted with coils of their own.  It is much like the wireless charging pads used to power up smartphones.  Indiana is pursuing a similar project in the next couple of years.

Clearly driving through a one mile stretch of roadway for minute or two is not going to provide a whole lot of energy by whatever coupling mechanism is used. Scaling up the technology represents a significant challenge at the very least.  How practical such a scheme is from both a technology and an economic perspective remains to be seen.  In any case, it is interesting to see that states are looking at various alternatives for providing access to charging infrastructure to the growing population of electrified vehicles.

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Governor Whitmer Announces Initiative for Nation-Leading Wireless EV Charging Infrastructure in Michigan

Photo, posted September 6, 2020, courtesy of Chris Yarzab via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Renewables Could Take Over By 2035 | Earth Wise

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A study by UC Berkeley looked at the prospects for renewable energy sources to become the primary source of energy in the United States over the next 15 years.  Even though fossil fuels continue to fill that role at present, the plummeting costs of alternative energy sources – primarily solar and wind power – are making them increasingly attractive on the competitive market.

These cost reductions have occurred much faster than what was anticipated even just a few years ago.  According to the study, it is technically and economically feasible for renewable sources to provide 90% of our electricity by 2035.

The Berkeley researchers took the available data on renewable energy and created two scenarios for the next 15 years.  The first has energy policy remaining as it is now, without ambitious policy changes that encourage the growth of renewable energy.  In that scenario, they estimated that 55% of the US energy infrastructure would come from renewables.  That amount will not produce the change needed to meet Paris Climate Agreement goals but would simply come about because of the dramatically lower costs for renewable energy.

The second scenario includes state and federal governments leading the way to finance and facilitate the energy reform needed for a greener 2035.  It also relies on the large-scale use of grid-scale batteries to store the energy collected from solar and wind installations for when it is needed.

Which scenario is more realistic will depend on several major influential factors, notably the trajectory and consequences of the COVID-19 pandemic as well as the results of the November elections.   These things will have a huge impact on the future of our energy system.

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Report: By 2035, 90 Percent of the US Could Be Powered by Renewables

Photo, posted May 25, 2019, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Concrete Production And Diminishing Coal Burning | Earth Wise

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Coal burning is still one of the primary means of generating electricity in the United States, but its use is diminishing and doing so fairly rapidly.  The coal burning process produces residual, incombustible materials.  One of them is fly ash, which is composed of fine, glassy, rounded particles rich in silicon, aluminum, calcium, and iron oxides.  Fly ash is captured from coal plant flue gas by precipitators and bag filters. It turns out that two-thirds of this fly ash is not dumped into landfills or impoundments, but rather is put to use.

Because of its chemical and physical characteristics, fly ash can substitute for a portion of portland cement in concrete.  Using this byproduct material in making cement actually reduces its cost. Beyond cost, the addition of fly ash as a so-called supplementary cementitious material or SCM improves concrete’s long-term strength and reduces porosity and permeability.  It reduces the risk of thermal cracking and provides good long-term mechanical properties.

The amount of fly ash used in concrete products increased by 5% between 2011 and 2017 while the amount produced dropped by 36%.  Concrete production continues to increase steadily while fly ash production is steadily dropping.

Therefore, the concrete industry is looking for alternative sources of SCM.  The most obvious is the approximately 1/3 of fly ash that hasn’t been used to make concrete.  Much of that is landfilled or ponded onsite at power plants.  So, opportunities exist for excavating or dredging and recovering these materials.

As coal burning goes away, concrete manufacturing needs to make some changes.

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What Does the Changing Face of Electricity Production Mean for Concrete?

Photo, posted February 16, 2017, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Heat And Plastic Bottles

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In the middle of July, Americans along the East Coast and in the Midwest suffered through a massive heat wave that saw actual temperatures soaring and so-called feels-like temperatures go much higher.  The punishing heat had many of us reaching for those plastic water bottles all day long as we tried to keep hydrated.

Studies have shown that those single-use plastic bottles do not handle the heat very well.  Most plastic items release tiny amounts of chemicals into the beverages or food that they contain.   But the hotter it gets, the more the substances in plastic can move into food or drinking water.  As temperature and time increase, the chemical bonds in plastics increasingly break down and chemicals are more likely to leach.

A study at Arizona State University in 2008 looked at how heat sped up the release of the element antimony in bottles made of the common plastic PET.  Antimony is used to manufacture the plastic and can be toxic in high doses.  At mild temperatures, very little antimony is released.  But PET and other plastics can leach a variety of chemicals when exposed to higher temperatures.

According to the FDA, the amounts of chemicals released by plastics are too miniscule to cause health problems.  However, scientists are still looking at the long-term effects of using so much plastic.  The question is whether all those small doses can eventually add up to something not so harmless.  Given that we don’t really know the cumulative effect of being surrounded by plastics in the goods we buy as well as the presence of microplastics in our water, it seems like a good idea to try to limit our exposure when alternatives are available.

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Exposed to extreme heat, plastic bottles may ultimately become unsafe

Photo, posted June 7, 2013, courtesy of Tim Stahmer via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Cleaning Up Shipping Fuel

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Cargo ships are significant sources of global air pollution because of their fuel oil.  Most ships burn something called “bunker fuel” which is a pitch-black, molasses-thick fuel made from the dregs of the oil refining process.  It is loaded with sulfur, so when it is burned it produces noxious gases and fine particles that can harm human health and the environment.  Because bunker fuel is made from petroleum refining residues, waste byproducts sometimes end up in the mix, making the stuff even a worse source of pollution.

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Septic Systems and Water Contaminants

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A recent study has shown that septic systems in the U.S. routinely discharge pharmaceuticals, consumer product chemicals and other potentially hazardous substances into the environment.   The comprehensive study, published in the journal Environmental Science & Technology, raises health concerns since these chemicals can end up in groundwater and drinking water supplies.

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A Climate-Friendlier Coolant

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Recently, negotiators from more than 170 countries reached a legally binding accord in Kigali, Rwanda to cut the use of hydroflurocarbons, or HFCs, which are chemical coolants used in air conditioners and refrigerators.  HFCs are just a small percentage of the greenhouse gases in the atmosphere, but they are supercharged greenhouse gases that have 1,000 times the heat-trapping potency of carbon dioxide.

[Read more…] about A Climate-Friendlier Coolant

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