Recently, I wrote about the usage emissions of gas (internal combustion engine), hybrid, and electric vehicles. When we only look at emissions out of the vehicle tailpipe or electric plant smokestack, electric vehicles are clearly the cleaner option for the marginal mile of travel.
But as several commenters noted, we really need to look at the lifetime emissions of a vehicle, including production and disposal.
The upcoming Tesla Model Y. Photo: Tesla
In August of 2018, the Low Carbon Vehicle Partnership published a report drafted by a consulting group that looked at dozens of studies that examined the lifetime emissions of cars, trucks, and other vehicles. This “meta study” found the most data available was for mid-sized passenger cars.
One key metric: the report uses metric tonnes CO2e as a measure of emissions. This unit of measure is defined as the equivalent mass of CO2 emissions that would produce the same greenhouse effect as all the emissions, including methane and other greenhouse gases that have a different effect than CO2. Vehicle production and use produce many other greenhouse emissions, and it is helpful to consolidate in the CO2e measure.
The study found that for model year 2015 mid-size cars, and assuming a lifetime range of 150,000 kilometers (about 93,206 miles), plug-in hybrid and battery-electric vehicles will have about 21 percent fewer lifetime greenhouse gas emissions. Lower tailpipe emissions were offset by the greenhouse gas-intensive production of producing a larger battery.
This European analysis assumes that the electric grid produces 500 grams of CO2e per kilowatt-hour of electricity produced. In Minnesota, that figure is closer to 389 grams (0.857 pounds) because about 29 percent of Xcel Energy’s power is generated from renewable sources. Thus, the lifetime greenhouse emissions of a battery-electric car on Minnesota’s cleaner grid would be roughly 30 percent fewer than a gasoline-powered car and 20 percent fewer than a traditional hybrid car.
Of course, the cleanest form of transportation in Minnesota is taking electric-powered light rail for your daily commute. The new Southwest extension starts service in 2023.
It’s a historic day for Minnesota as the first rail arrives to start #swlrt construction pic.twitter.com/uQdGt1CHDI
— METRO Green Line Extension (@GreenLineExtMN) May 13, 2019
What are your wheels? How are you reducing your greenhouse gas emissions? Share your new trends and old favorites in the comments.