Over the last 18 months, several studies have begun a fresh debate about whether battery-powered electric vehicles are really better for the environment than gas-powered ones. The key point is asking how much the source of the electricity that powers an EV contributes to its green credentials. The answer: significantly.
Christopher Tessum, author of a November 2015 University of Minnesota study on how the various ways to power a car affect human health, told Popular Mechanics that many alternative fuel vehicles don’t end up leading to significant decreases in “air quality-related health impacts.”
Tessum added, "The most important implication is that electric vehicles can cause large public health improvements, but only when paired with clean electricity. Adapting electric vehicles without taking steps to clean up electric generation would be worse for public health than continuing to use conventional gasoline vehicles."
A working study on the environmental benefits from driving EVs published by the National Bureau of Economic Research in June 2015 came to a similar conclusion, with more of a focus on geography. “What we find is that the benefits are substantially different depending on where you are in the country,” Stephen Holland of the University of North Carolina, Greensboro, who co-authored the study, told CityLab. “The real big take-home message is: location, location, location.”
Why Does It Matter Where I Live?
The key problem is that many parts of the United States still rely on electricity generated by fossil fuels. According to the EPA, the electrical power sector accounted for 32 percent of the country's total greenhouse gas emissions in 2012, with fossil-fired power plants being the largest source of CO2 emissions. The worst offenders are coal- and gas-fired power plants. According to Tessum, without the continued development of cleaner electricity, EVs powered by fossil fuels would eventually be worse for public health than conventional gas-powered cars.
This is called the “long tailpipe” argument. While EVs have zero tailpipe emissions, their true “tailpipe” comes out of the large smokestacks you see above power plants. As science overwhelmingly tells us, electricity generated from fossil fuels contributes toward unhealthy air quality, acid rain and global climate change.
In the short term, if you live in an area where fossil fuels are not the primary source of electricity generation, then there is little to no argument that your EV is better for the planet than a gas-powered car. You can check where your power comes from with the EPA's “Power Profiler.” Simply enter your zip code and compare the fuel mix and air emissions rates of the electricity in your region to the national average, which is 30 percent gas-powered, 37 percent coal-powered, 19 percent nuclear and 12 percent hydro and non-hydro renewable.
Does This Mean I Shouldn't Drive an EV?
Taken at face value, these two reports seem to indicate that you should only drive an EV if you live in an area that generates a substantial amount of clean electricity. However, according to a two-year study published in November from the Union of Concerned Scientists, that statement is misleading. The UCS study concludes that over their life cycle, current EVs powered by current electricity sources still beat current gas-powered cars in lifetime global warming emissions.
By applying the cradle to grave methodology, the UCS says EVs produce less than half the global warming emissions of comparable gas-powered cars (even when factoring in the higher emissions during manufacture, courtesy of the EV’s lithium-ion battery). According to the study, the average EV produces global warming emissions equal to a 68 miles per gallon (Mpg) fuel economy gas car. While UCS concedes that EVs contribute a not-insignificant amount of global warming emissions from their operation, driving the average EV in any region of the country produces lower emissions over its lifespan than the average gas-powered car clocking in at 29 Mpg. Additionally, the potential for EVs to be powered by clean electricity exists, much more so than with gas-powered vehicles.
Image link
This graphic from the Union of Concerned Scientists illustrates how driving an EV in each region compares with driving a gas-powered car when it comes to emissions. The regions are based on the group of power plants that serve as each one’s primary source of electricity.
To determine how green driving an EV in your area is today, use the UCS's EV Emissions Tool. This calculates how much global warming your EV will produce based on your locally available power sources. For example, a Nissan Leaf charged in South Carolina will produce as much pollution as a gas-vehicle getting 70 Mpg, whereas in Idaho it would be closer to 104 Mpg. But wherever you are, according to the UCS, an EV is still greener than a gas-only car.
Can My EV Ever Be Truly Green?
A long-term, national shift away from generating electricity via fossil fuels would result in EVs being powered by energy from entirely renewable sources. That is a true zero-emission vehicle. Thankfully, however, you don't have to wait for your local power company to install wind turbines before you can achieve this. You can take matters into your own hands.
To accurately regulate the cleanliness of the electricity your car uses, create your own. If you own your home, install solar panels on its roof to generate clean electricity, then purchase and install a Level 2 Electric Vehicle Supply Equipment unit (EVSE). These charging docks can be hardwired or plugged into your home (via a NEMA 14-50 outlet) and will charge your EV in as little as four hours (you can charge with a regular 110-volt outlet, but that takes 8–12 hours for a full charge).
The prospect of installing solar panels on your home once meant a bill in the tens of thousands of dollars. Today, options for financing and leasing can often result in lower monthly bills than you pay your power company. By pairing solar panels with an in-home EV charger, you can suck clean energy right from the sky and power your EV with virtually zero cost to the planet and, eventually, zero cost to you.
Jennifer Tuohy loves to use technology to help us live a more sustainable lifestyle. She gives tips on how driving an EV car and having a home charging station can reduce your carbon footprint. If you are looking to install an electric car charger in your home, visit the Home Depot to see all your EV charger options.
All MOTHER EARTH NEWS community bloggers have agreed to follow our Blogging Best Practices, and they are responsible for the accuracy of their posts. To learn more about the author of this post, click on the byline link at the top of the page.
At MOTHER EARTH NEWS for 50 years and counting, we are dedicated to conserving our planet's natural resources while helping you conserve your financial resources. You'll find tips for slashing heating bills, growing fresh, natural produce at home, and more. That's why we want you to save money and trees by subscribing through our earth-friendly automatic renewal savings plan. By paying with a credit card, you save an additional $5 and get 6 issues of MOTHER EARTH NEWS for only $12.95 (USA only). 
First of all in your paragraph 'Why does it matter where I live' you have facts wrong and make a common mistake that many do. First of all I assume you are talking about Natural Gas fired power plants which are the cleanest in existence if they have been built in the last 20 to 25 years, Oil would be the next cleanest and unless the coal plant was less than 10 years old it would be way dirtier. You also use the word gas to mean gasoline and natural gas. I addition there are natural gas powered cars and trucks which are very clean, but no gasoline powered generation unless you count small intermittently used home generators. This makes your article confusing to the unknowing as well as inaccurate. One of the biggest sources of CO2 by the way is released from cow poop from our many industrial sized food factory farms. EV's are nice if you live in the city and do not go far, and though they have come down in cost, for most people they do not justify the cost. Most people just do not have the funds to buy and maintain on. As of today, the longest range you can expect is 220 miles and they are not family sized. As with anything electric, unless it is hydro, solar or wind generated electricity, it does increase pollution at the generation site. If we really want to make some progress, Electric generators should be putting in solar and wind on their own to mitigate their peaks if nothing else, and as you see, none of them are jumping at doing that. Unless solar is done commercially, it still is a rich man's game no matter how much the solar panel cost has come down. Solar and wind for a residence only make sense off the grid where they are a great boon.
Electric motors are greater than 90% efficient. Fossil fuel engines are less than 30% efficient! Even if all the electricity for an electric car is made from coal, the electric car will pollute less than the fossil fuel car. It takes a fossil fuel motor at least 3X the energy to move a car the same distance as an electric motor. Hands down there is no comparison between electric Cars and fossil fueled cars. Electric is cleaner under any conditions you make.
Even if all the electricity is made with coal or fossil fuels electric cars will still generate less CO2 than gasoline or diesel engines. Electric motors are greater than 90 % efficient while gasoline engines are 30% efficient. When you use fossil fuel car you are throwing away more energy than you are using to propel the car. I cannot believe Mother Earth published this garbage!
Even if all the electricity is made with coal or fossil fuels electric cars will still generate less CO2 than gasoline or diesel engines. Electric motors are greater than 90 % efficient while gasoline engines are 30% efficient. When you use fossil fuel car you are throwing away more energy than you are using to propel the car. I cannot believe Mother Earth published this garbage!
Thank you for your great job,this is really a good post. You give something to think about. Environmental issues are a big problem for this time. There are a lot of studies and a lot of theories about EVs and environment. We are always focused on EVs like city cars or urban transport network. But it's important to understand that the electric vehicles world is not just that. It's proved that, driving electric city cars, people can reduce the quantity of polluting emissions without changing their habits. On the other side, many factories are buying EVs to use during the operations. This happens because EVs are now so performing to be able to increase the productivity decreasing the emissions. In fact, industries and home heating alone genetate the most of CO2 emissions. Thanks!:) http://www.alke.com
One other factor to consider is the environmental impact of the production of these vehicles...the mining for raw materials (iron for steel, heavy metals for electronics and batteries, rubber for the tires, etc...). Then these materials must be transported to the production facilities...usually by rail, heavy truck, or ship. Then the factory needs to utilize energy to build the vehicle. After that, back to transportation to the dealership. These vehicles use up a massive amount of energy before they are ever driven. So a refer you take all this into account, you need to compare the production impacts of all vehicle type to truly decide which is the best option