reductions

Emissions And The Pandemic | Earth Wise

January 3, 2022 By EarthWise Leave a Comment

The early months of the COVID-19 pandemic saw drastic reductions in travel and other economic sectors across the globe that greatly decreased air pollution and greenhouse gas emissions. These dramatic changes occurred quite suddenly. This abrupt set of changes gave scientists the unprecedented opportunity to observe the results of changes that would ordinarily have taken years if they came about through regulations and gradual behavior shifts.

A comprehensive study by Caltech on the effects of the pandemic on the atmosphere has revealed some surprising results.

The biggest surprise is that even though carbon dioxide emissions fell by 5.4% in 2020, the amount of CO2 in the atmosphere continued to grow at about the same rate as in previous years. According to the researchers, the reasons are that the growth in atmospheric concentrations was within the normal range of year-to-year variations caused by natural processes and, in addition, the ocean did not absorb as much CO2 because of the reduced pressure of CO2 in the air at the ocean’s surface.

A second result involved the reduction in nitrogen oxides, which led to a reduction in a short-lived molecule called the hydroxyl radical, which is important in breaking down gases including methane in the atmosphere. Reducing nitrogen oxides is advantageous with respect to air pollution, but they are important for the atmosphere’s ability to cleanse itself of methane. In fact, the drop in nitrogen oxide emissions actually resulted in a small increase of methane in the atmosphere because it was staying there longer.

The main lesson learned is that reducing activity in industrial and residential sectors is not a practical solution for cutting emissions. The transition to low-carbon-emitting technology will be necessary.

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Emission Reductions From Pandemic Had Unexpected Effects on Atmosphere

Photo, posted March 22, 2020, courtesy of Greg via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Batteries On Wheels | Earth Wise

December 24, 2021 By EarthWise Leave a Comment

Transportation accounts for nearly a quarter of the direct carbon dioxide emissions coming from burning fuel. As a result, electrification of transport is one of the major ways we can reduce emissions. Increasing the number of electric vehicles over time is essential for meeting emissions targets.

But electric vehicles have the potential to do more than deliver emissions reduction; they can also provide other energy services.

More and more electric cars provide over 200 miles of driving range, but most cars are actually driven no more than 30 miles a day. As a result, the fleet of electric cars represents a huge bank of energy stored in battery packs and mostly sitting around unused. This presents an opportunity to leverage this resource.

Car battery packs could be used to absorb excess renewable energy generated in the middle of the day (for example from solar installations) or at night (from wind farms) and potentially then to export stored energy to power homes and support the grid. This energy system is known as V2G, or vehicle-to-grid technology.

The University of Queensland in Australia has launched a unique international trial to see if the spare battery capacity in vehicles could be used for these purposes. The university has partnered with Teslascope, which is an online analytics platform used by Tesla owners to track the performance of their cars. Tesla owners wishing to be part of the study authorize the collection of their data and, in turn, receive a free 12-month subscription to the Teslascope service. The study will collect data from Tesla owners in Australia, the US, Canada, Norway, Sweden, Germany, and the UK.

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Can EV spare battery capacity support the grid?

Photo, posted February 8, 2009, courtesy of City of St Pete 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.

Wind Power Update | Earth Wise

October 8, 2021 By EarthWise Leave a Comment

The Department of Energy recently released three reports showing record growth in land-based wind energy, a growing number of offshore wind projects, and the continuing reduction in the cost of wind power.

The U.S. installed a record amount of land-based wind energy in 2020. In total, 16,836 MW of new utility-scale land-based wind power capacity was added during the year, representing $24.6 billion in new wind power projects. This was more added than from any other energy source and represented 42% of new U.S. energy capacity.

For the year, wind energy provided more than 10% of in-state electricity generation in 16 states. Notably, wind provided 57% of Iowa’s electricity and more than 30% in Kansas, Oklahoma, South Dakota, and North Dakota.

As wind turbines continue to grow in size and power, they are producing more energy at lower cost. Turbine prices have gone from $1,800/kW in 2008 to $770-850/kW now.

The pipeline for U.S. offshore wind energy projects has grown to 35,324 MW, a 24% increase over the previous year. The Bureau of Ocean Management created five new wind energy areas in the New York Bight with a total of 9,800 MW of capacity.

Distributed wind power, which are systems connected on the customer’s side of the power meter as opposed to those on the utility side, also saw increased growth last year.

Wind power is a key element in the adminstration’s goal of having a decarbonized electricity sector by 2035.

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DOE Releases New Reports Highlighting Record Growth & Declining Costs Of Wind Power

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Earth Wise is a production of WAMC Northeast Public Radio.

Lower Power Sector Emissions | Earth Wise

September 16, 2021 By EarthWise Leave a Comment

A combination of factors led to emissions from the U.S. power sector dropping 10% between 2019 and 2020, which was the largest one-year drop measured since annual reports first began being published in 1997.

The coronavirus pandemic was certainly a contributing factor, but the drop in emissions is part of a long-term trend being driven by increasing reliance on renewable energy sources, diminishing use of coal, and improving energy efficiency.

Between 2000 and 2020, power generation from solar, wind, and geothermal generation more than doubled. Coupled with the declining use of coal power, power sector emissions during that period dropped by 37% even though the U.S. gross domestic product grew by 40% over the same years. Overall, at this point zero-carbon electricity sources – which include wind, solar, geothermal, hydropower, and nuclear power – provide about 38% of U.S. electricity.

The Biden Administration has set a target of 100% zero-carbon power by the year 2035. Given that the costs of wind and solar power continue to fall, there are power companies pushing for setting an intermediate goal of 80% clean power by 2030.

According to recent research, the increasingly attractive cost of renewable power along with the job creation associated with it means that reaching at least 90% clean power by the year 2035 could be achieved at no extra cost to consumers. Being able to separate economic growth from emissions makes it far more likely that the goals of decarbonization can be met without encountering economic resistance.

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U.S. Power Sector Sees Biggest One-Year Drop in Emissions in More Than Two Decades

Photo, posted June 30, 2019, courtesy of Stephen Strowes via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Gulf Of Mexico Dead Zone | Earth Wise

July 19, 2021 By EarthWise Leave a Comment

Every summer, a so-called dead zone forms in the Gulf of Mexico. It is primarily caused by excess nutrient pollution from human activities in urban and agricultural areas throughout the Mississippi River watershed.

When these excess nutrients reach the Gulf, they stimulate excess growth of algae, which eventually die and decompose, depleting oxygen as they sink to the bottom. These low oxygen levels near the Gulf bottom cannot support most marine life. Animals that are sufficiently mobile – such as fish, shrimp, and crabs – generally swim out of the area. Those that can’t move away are stressed or killed by the low oxygen.

A team of scientists funded by the National Oceanic and Atmospheric Administration issues an annual forecast for the dead zone based upon a suite of models that incorporate river flow and nutrient data.

The 2021 forecasted area is somewhat smaller than, but close to, the five-year measured average for the dead zone, which is 5,400 square miles, roughly the size of the state of Connecticut. Each year, these forecasts are reported as comparisons to long-term averages, but the problem is that the long-term average is unacceptable.

The Interagency Mississippi River and Gulf of Mexico Hypoxia Task Force has set a goal of reducing the size of the dead zone to a five-year average of 1,900 square miles – about a third of the current average.

Large reductions in nutrient loads have been called for in federal and state action plans for nearly 20 years, but clearly these reductions have not yet been sufficient. The Interagency Task Force continues to provide information for managing nutrient loads in the Mississippi River Basin.

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Average-sized ‘dead zone’ forecast for Gulf of Mexico

Photo, posted October 6, 2020, courtesy of Christine Warner via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Strategies To Cool Off Cities | Earth Wise

July 2, 2021 By EarthWise Leave a Comment

Heatwaves in cities are becoming increasingly common and increasingly intense. The warming climate is a big factor, but it is the nature of our cities that really drives up temperatures. Solar radiation stored throughout the day on asphalt and buildings is released slowly during the night, which generates significant heat stress.

A study carried out by a major Barcelona university and published in the journal Urban Climate looked at the effectiveness of various ways to mitigate the heating effects in cities. In particular, the study examined the effects of the use of white roofs on buildings and the expansion of urban green areas with daily irrigation in the Barcelona metropolitan area. It simulated various scenarios incorporating combinations of these two mitigation strategies.

The strategy with the greatest impact was a combination of the use of both white roofs and the addition of six urban parks, which is a target set by the Barcelona Urban Master Plan. This scenario resulted in an average temperature reduction of 2.25 degrees Fahrenheit. The maximum reduction occurs during the mid-afternoon with a reduction of 7 degrees and the combination still provides more than 3 degrees of reduction at 9 pm. Reducing temperatures this way also results in a reduction in energy consumption, with 26% less spending on air conditioning.

The 2-pronged strategy combines the benefits of reducing the temperature at night due to more urban green areas with the reduction of daytime heat due to both the increased reflectivity of white roofs as well as the irrigation of the green areas.

The study demonstrates how modeling efforts can help urban planners to counteract the impacts of heatwaves, which are likely to increase with climate change and intensification of urbanization.

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White roofs and more green areas would mitigate the effects of heat waves in cities

Photo, posted January 16, 2011, courtesy of Sean MacEntee via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

What’s The Best Way To Reduce Emissions? | Earth Wise

April 1, 2021 By EarthWise Leave a Comment

A carbon tax is a fee imposed on the burning of carbon-based fuels, like coal, oil, and gas. It’s one way to make the users of carbon fuels pay for the climate damage caused by releasing carbon dioxide into the atmosphere.

According to a new study by researchers at Ohio State University, putting a price on producing carbon is the cheapest and most efficient policy change that legislators can make in order to reduce climate change-causing emissions.

The case study, which was recently published in the journal Current Sustainable/Renewable Energy Reports, looked at the impact that a variety of policy changes would have on reducing carbon dioxide emissions from electricity generation in Texas. The researchers found that assigning a price to carbon, based on the cost of climate change, was most effective.

The study did not look at how policy changes might affect the reliability of the Texas power system, an important consideration after the failure of the state’s power grid following winter storms in February.

But the study did examine other policies and found that they were either more expensive or not as effective, including mandates that a certain amount of energy in a portfolio come from renewable sources. Subsidizing renewable energy sources was also found to be less effective.

According to researchers, market-based solutions have previously proven effective combating environmental issues. For example, a cap-and-trade approach was used to reduce levels of sulfur dioxide, one of the chemicals that causes acid rain.

For the sake of the climate, we should probably tax carbon.

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Want to cut emissions that cause climate change? Tax carbon

What’s a carbon tax?

Photo, posted June 5, 2011, courtesy of John Englart via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

The Pandemic And Global Temperatures | Earth Wise

March 12, 2021 By EarthWise Leave a Comment

The early months of the Covid-19 pandemic last year saw dramatic reductions in travel and many forms of commerce. With much of human activity greatly curtailed, greenhouse gas emissions were greatly reduced. And yet, all of that did not slow down global warming: 2020 ended up tied with 2016 as the warmest year on record and atmospheric greenhouse gas levels reached a new high.

In order to understand how this came about, it is necessary to understand the complex climate influences of different types of emissions from power plants, motor vehicles, industrial facilities, and other sources. The fact is that some types of pollution actually have a cooling effect rather than contributing to global warming.

Tiny industrial pollution particles called aerosols actually make clouds brighter, causing them to reflect away more solar heat from the surface of the planet. During the drastic shutdown last year, the biggest emissions decline was from the most polluting industries. The reduction of aerosols had immediate, short-term effects on temperatures. These types of pollutants are very bad for human health, but when they are present, they do have the effect of reducing temperatures.

It is important to keep in mind that carbon dioxide spreads through the Earth’s atmosphere and stays there for a century or more, trapping heat on a global scale. Industrial aerosols stay relatively concentrated in the region where they are emitted and are often removed by rain and winds within a few weeks. So, their cooling effect doesn’t spread very far or last very long.

Overall, the initial pandemic slowdown probably didn’t have any real long-term impact on the climate but over the short term, the effects were not as simple as one might expect.

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Covid-19 Cut Gases That Warm the Globe But a Drop in Other Pollution Boosted Regional Temperatures

Photo, posted July 7, 2020, courtesy of Joey Zanotti via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Global Warming Could Stabilize | Earth Wise

February 19, 2021 By EarthWise Leave a Comment

The world has been heading toward climate disaster with the effects of greenhouse gas-induced warming looming larger and larger. But recent analysis published in Nature Climate Change offers hope that rapidly eliminating emissions could stabilize global temperatures just within a couple of decades.

For quite some time, it has been assumed that further global warming would be locked in for generations regardless of the extent of emissions reductions going forward. This conclusion was based on having a certain carbon dioxide concentration in the atmosphere which would linger for hundreds of years even if emissions were reduced.

Recent analysis takes into account the dynamism of the Earth’s natural systems which could actually reduce atmospheric CO₂ content because of the huge carbon absorption capacity of oceans, wetlands, and forests. The key requirement is to drastically reduce emissions so that these natural systems can take over.

More than 100 countries have pledged to get to net zero emissions by 2050. That means they will emit no more carbon dioxide than is removed from the atmosphere by such actions as restoring forests. The UK, Japan, and the European Union are among the countries that have set this zero target, and the United States is joining the club.

Climate models show that a global temperature rise of 2 degrees Celsius over that of the pre-industrial period would lead to global calamities that include punishing heatwaves, flooding, and mass displacement of people. The world has already heated up by 1.1 degrees and governments have committed to restrain the rise to less than 1.5 degrees under the Paris Climate Agreement.

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Global Warming Could Stabilize Faster than Originally Thought If Nations Achieve Net Zero

Photo, posted September 10, 2017, courtesy of Ron Cogswell via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

A Large Drop In U.S. Greenhouse Gas Emissions | Earth Wise

December 29, 2020 By EarthWise Leave a Comment

Greenhouse gas emissions in the U.S. in 2020 are on track to be at their lowest level in nearly 30 years as a result of the COVID-19 pandemic. U.S. emissions haven’t been this low since 1983, when the economy was not even 40% of its current size.

According to a new study by the research group BloombergNEF, U.S. emissions for the year will be 9% lower than they were in 2019, which will be the largest yearly drop on record. The report also anticipates that whatever happens in the pandemic, 2021 emissions will be well below pre-COVID levels as well.

The pandemic has inadvertently put the U.S. back on track to meet its original commitments to the Paris Climate Agreement, despite the fact that we have pulled out the agreement. The incoming administration plans to return the U.S. to the pact.

Overall, U.S. emissions have been trending downward since 2008, primarily as a result of the lower dependence of the power sector on coal. The report estimates that in the absence of the pandemic, 2020 emissions would have been 1% lower than last year’s.

The dramatic drop in emissions is not really a great cause for celebration. Achieving significant emission reductions through massive economic hardship and societal disruption does not point the way towards making progress on climate change. The economic upturn that will undoubtedly occur when the pandemic loses its grip on the world will lead to rebounding levels of greenhouse gas emissions. But as is the case with all major crises, the current situation does present a chance to turn this temporary downturn in emissions into a more permanent one by making appropriate investments and policy changes.

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Due to COVID-19, 2020 greenhouse gas emissions in the U.S. are predicted to drop to lowest level in three decades

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Earth Wise is a production of WAMC Northeast Public Radio.

Electric Cars And The Environment | Earth Wise

April 20, 2020 By EarthWise Leave a Comment

There are articles in the media all the time questioning whether electric cars are really better for the environment than those powered by fossil fuels. The usual argument is that once emissions from vehicle production and electricity generation are taken into account, electric cars are no greener than gas cars, or even worse for the environment. Of course, these arguments tend to be made by oil companies and their supporters.

A new study by three European universities looked at this very issue in detail. They carried out a life-cycle assessment in which they not only calculated greenhouse gas emissions generated when using cars, but also in the production chain and waste processing.

Their conclusions are that under current conditions, driving an electric car is better for the climate than conventional gasoline cars in 95% of the world. The only exceptions are places like Poland, where almost all electricity comes from coal-fired plants.

Average lifetime emissions associated with electric cars are up to 70% lower than gas cars in countries like Sweden and France and about 30% lower in England.

It is important to note than in a few years, even inefficient electric cars will be less emission-intensive than gas cars because electricity generation is becoming less carbon-intensive all the time. The study projects that by 2050, half of the world’s cars will be electric resulting in carbon dioxide emission reductions of 1.5 billion tons.

The study states that the idea that electric cars could increase emissions is a myth. The detailed study has run the numbers for all around the world and even in the worst-case scenario, there would be a reduction in emissions in almost all cases.

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Electric cars better for climate in 95% of the world

Photo, posted February 13, 2019, courtesy of Guillaume Vachey via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Solar And Wind Power In China | Earth Wise

April 2, 2020 By EarthWise Leave a Comment

Reducing greenhouse gas emissions is a global challenge and nowhere is that challenge greater than in China. China accounts for 30% of the world’s emissions and much of that comes from coal power plants. If the world is going to reach its climate targets, China is going to have to replace as much as possible of its current power mix with renewable energy.

As of 2018, China still made 69% of its electricity from fossil fuels. Its vast coal reserves have driven its rapid industrialization and better standard of living. But terrible air pollution problems along with climate issues have led to heavy investments and rapid expansion of both wind and solar power in China.

China is now a world leader in renewable energy, both in terms of producing and using renewable power. At the start of 2016, China had installed a total of 145,000 megawatts of wind power, which is 3,000 MW more than all 28 European Union countries combined. And this has occurred even though China only started developing their wind power industry 30 years later than the first EU countries.

Until 2009, China exported almost all the solar panels it produced. But gradually China began to use solar energy in a big way. The industry took off in 2014, and growth has been exponential. Solar power production in China is now almost as extensive as wind power.

One has to consider that much of China’s electricity production is used by industries that produce products for the rest of the world. In effect, these are exported emissions. China has a long way to go in replacing its fossil fuel generation and we all have a stake in China succeeding in the task.

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China’s rapid development of solar and wind power

Photo, posted November 12, 2007, courtesy of Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Food Waste And Access To Groceries | Earth Wise

March 19, 2020 By EarthWise 1 Comment

One-third of all food produced is wasted, which turns out to be a major contributor to carbon emissions. Most of the carbon emissions associated with food waste are related to the production of the food. Reducing waste would trickle through the supply chain over time and ultimately less food would be produced.

A study at Cornell’s SC Johnson College of Business looked at a particular strategy for reducing food waste’s environmental impact: opening more grocery stores.

It turns out that the more stores there are, the lower food waste will be. Cornell Professor Elena Belavina created a model that incorporates data from the grocery industry, the U.S. Census Bureau, and other academic studies.

When applied to Chicago, which is typical of many American cities, the model predicts that by adding just three or four markets within four-square-mile area, food waste would be reduced by 6 to 9 percent. This would achieve an emissions reduction comparable to converting more than 20,000 cars from fossil fuels to electric power. According to the model, not only would food waste be reduced, but so would grocery bills. By trimming food waste and travel costs, consumers would spend up to 4% less.

Most big cities are well below their ideal density of grocery stores that would minimize food waste. When consumers can purchase perishable goods nearby, they shop more often but buy less each time. There is less food sitting at home, so there is a much lower likelihood that food will spoil.

New York City, which has an abundance of produce stands and neighborhood markets, comes close to having the ideal density of markets. Basically, the way to reduce food waste is to bring less groceries home.

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Better access to groceries could reduce food waste, emissions

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Earth Wise is a production of WAMC Northeast Public Radio.

Reducing Air Pollution With Plants | Earth Wise

January 15, 2020 By EarthWise Leave a Comment

New research by Ohio State University suggests that adding plants and trees to the landscapes near factories and other pollution sources could reduce air pollution by an average of 27%. In addition, the study indicates that, in many cases, plants may be a cheaper option for cleaning the air than more technological approaches.

The study looked at public data on air pollution and vegetation on a county-by-county basis across the lower 48 states. It then calculated what adding additional trees and plants might cost. The calculations included the capacity of current vegetation to mitigate air pollution as well as the effects that restorative planting might have on pollution levels.

In 75% of the counties analyzed, it was cheaper to use plants to mitigate air pollution rather than add technological interventions such as smokestack scrubbers to the sources of pollution. The results varied according to the pollution source. For example, technology is cheaper at cleaning the air near industrial boilers than ecosystem approaches. For the broad manufacturing industry, one approach or the other was favorable, depending on the type of factory.

Adding trees or other plants generally can lower air pollution levels in both urban and rural areas, although success rates depend on a variety of factors including how much land is available to grow new plants and current air quality.

Reducing air pollution is critical to public health. An estimated 4 in 10 people in the U.S. live in areas with poor air quality, leading to health issues including asthma, lung cancer, and heart disease. The study shows that nature should be part of the planning process for industry to deal with air pollution.

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Nature might be better than tech at reducing air pollution

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Earth Wise is a production of WAMC Northeast Public Radio.

Other Ways To Cut Vehicle Emissions

October 17, 2019 By EarthWise Leave a Comment

It is pretty clear that the way to drastically reduce vehicle greenhouse gas emissions is to switch as many vehicles as possible to electric power. As a result, more and more localities are putting in place policies that encourage electrification.

While there is no doubt that electrification is the long-term solution to vehicle emissions, a recent study by MIT and the Ford Motor Company found that, in the short term, there are some places in the US where electric cars are not the best way to reduce emissions.

The study looked at a variety of factors that affect the relative performance of vehicles. These include the role of low temperatures in reducing battery performance, regional differences in the average number of miles driven annually, and significant differences in the way electricity is generated in different parts of the US.

The results showed that electric vehicles definitely provide the greatest impact in reducing greenhouse gas emissions for most of the country – and particularly on both coasts and in the south – but that there are some places in the upper Midwest where the greatest reduction would be achieved by the use of lightweight gasoline-powered vehicles.

In places like parts of Wisconsin and Michigan, it is mostly rural, there are cold winters, and electricity is predominantly generated by coal-powered plants. In these places, if gas-powered lightweight cars were to be used, the overall benefit would be greater than that of electric cars. Unfortunately, there are no high-volume lightweight gasoline-powered mid-sized cars on the market in the US. Ironically, the only cars of that class using lightweight aluminum construction are Teslas.

While electric cars are truly the long-term solution, the study does demonstrate the benefits of reducing the weight of vehicles.

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