Wait, don’t jump the gun and says, “solar electric” is the green car with the best carbon dioxide emissions. Well, you’re right, but bear with me, it’s a little more complicated than that.
Lifecycle emissions, even for green cars, include manufacturing, recycling, as well as fuel extraction and refining. For electric vehicles, you’d have to include power production emissions. After all, although and electric vehicle emits no emissions on its own, it still needs to get energy from somewhere. Even solar panels have their associated emissions. What happens when you crunch all the numbers, say, for four conventional vehicles and one electric vehicle on four different power grids?
For this comparison, we consider four generic gasoline-powered conventional vehicles, whose fuel economy range from 20 to 50 miles per gallon (mpg). Unsurprisingly, at 20 mpg, lifecycle carbon dioxide emissions amount to 589 g CO2/mi (grams carbon dioxide per mile), this is the most heinous of the group. You can drive an electric vehicle, in this case the 29 kWh/100mi (kilowatt-hours per 100 miles) Nissan Leaf, recharge it on a coal-fired power plant, and still emit less carbon dioxide than a 20 mpg conventional vehicle, or 416 g CO2/mi.
This is where things start to get sketchy when comparing these green cars, the electric vehicle its fuel-sipping conventional counterparts. For example, while the electric vehicle, charging on coal, generates 416 g CO2/mi, the 30 mpg conventional vehicle, on the same road, generates 413 g CO2/mi, a difference barely worth mentioning. Stepping up to charging your electric vehicle on an oil-fired power plant, the electric vehicle generates 349 g CO2/mi, and the 30 mpg gasoline-powered vehicle at her side generates 326 g CO2/mi, another difference barely worth mentioning. The results are similar, comparing an electric vehicle charging on natural gas and a 50 mpg conventional vehicle, 257 g CO2/mi and 273 g CO2/mi, respectively. Although, to be certain, related natural gas extraction emissions could be far higher than anyone ever thought.
Really, the only way to make a significant cut in you carbon dioxide emissions, a truly green car, is to charge only on solar power, which makes this electric vehicle responsible for a mere 127 g CO2/mi.
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