Electric Vehicles & Climate Change

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Skeptics sometimes argue that plug-in electric vehicles (EVs, for short) simply shift the emissions source from the tailpipe to the smokestacks. However, the inherent efficiency advantages of electricity over internal combustion still generally make EVs a better environmental choice, and an even better long- term solution to promote energy security, combat climate change, and improve air quality. And, unlike conventional vehicles, EVs also become greener as energy production technology for electricity continues to improve. As a result, the environmental footprint from driving an EV will continue to decline as we transition to cleaner, renewable energy sources like wind, solar, and biomass.

Michigan's Current State of Charge

state of chargeThe 2012 Union of Concerned Scientists report, State of Charge: Electric Vehicles’ Global Warming Emissions and Fuel-Cost Savings Across the United States, compared global warming emissions from EVs with those emitted from gasoline-powered vehicles in each region of the U.S. electricity grid. The report shows that areas with the “cleanest” electricity grids also have EVs with the lowest greenhouse gas-related emissions, while regions that use greater amounts of coal have the highest. These emissions can be shown as mpgghg,, with a national average of 54 mpgghg.

Michigan, which operates in one of the highest ghg-emitting regions in the State of Charge study, nonetheless falls within the “good” range of global warming emissions where EVs achieve approximately 38 mpgghg--comparable to the best gasoline or average hybrid models available today (see Figure 1).

The good news is that EV-related emissions in Michigan will continue to decline as the state takes steps to improve its electricity grid with its renewable energy standard of 10 percent by 2015. The state has the potential to reduce its global warming emissions even more in the years ahead as it considers options for increasing its standard to as high as 30% renewables. (See Michigan’s Energy Future report at: http://michigan.gov/energy.)

Michigan’s Future State of Charge

An analysis by the Michigan-based Ecology Center shows emissions from EVs in the state will improve to 50 mpgghg by 2015 when it meets its 10% RES target. If the State of Michigan were to increase its grid- generated mix of renewable energy to 25% of electricity produced in 2025, emissions from EVs could be as high as 97 mpgghg. The figure below illustrates this emissions scenario, assuming also that overall vehicle efficiency continues to increase over time.

Today, driving an EV in Michigan still contributes less global warming emissions than driving a comparable gasoline vehicle. But driving that same EV will result in even fewer emissions over the coming decade as Michigan increases the amount of electricity generated from renewable sources. For those EV owners installing their own renewable energy systems, emissions have the potential to achieve near-zero levels—or very high mpgghg. In short, by coupling EVs with renewable energy, we can take Michigan into a new era of sustainable transportation and energy.

Who We Are

Built by Michigan brings together businesses, workers, families, electric-vehicle owners, environmental organizations and community leaders to advance the manufacture and sale of electric vehicles in Michigan. We work with cities and industry leaders to develop and disseminate best practices for electric-vehicle integration and adoption at the municipal level. Visit the link below for more information on the case for electric vehicles and renewable energy.