Carbon Footprint

 

We were at an EV meet-up recently. It was at a public park and a woman walking through the park stopped to see what was going on. As the conversation turned to sustainability, her question was “but what about the batteries and the carbon footprint related to them?”

That’s a good question and one that often comes up when talking about EVs. From the concerns over mining the lithium to disposing of spent batteries, it’s a valid concern. However, no manufacturing process or mechanical activity is without some footprint.

Unless we all go back to walking (without shoes), there will be SOME environmental impact from what we do. The goal is to minimize that as much as possible while still living our first-world lifestyle. You may disagree with that last sentence, but really, I don’t think very many of us want to give up the perks of a first-world culture, so how can we maximize our sustainability and minimize our footprint?

In the chart above, you can see how electric cars over their life have a much smaller carbon footprint than ICE (internal combustion engine) cars. While electric cars have a higher manufacturing impact and a significantly higher upstream impact, they are much lighter on the earth than ICEs. (Upstream is the very beginnings of the entire process, which includes the mining and sourcing of the raw materials: lithium for the batteries included).

However, we never should only look at the initial cost or impact of anything. For example, WHERE you live has a far greater impact than the efficiency of your home. A relatively inefficient home in an urban, walkable area, actually has a smaller carbon footprint than a very efficient home in the suburbs. But that is another post for another time.

So the third category in the chart is lifetime emissions from the tailpipe. Since EVs have no tailpipe, they have no emissions. ICE cars, however, emit more greenhouse gases just from their tailpipes than the entire impact of manufacturing and upstream costs of an EV.

We have been trying to “walk the talk” in this regard. That is why we committed to buying an EV. That’s why we committed to living in an urban, walkable area AND building an efficient home. Did that cost more money initially? Absolutely. But what are the benefits?

First, the economic ones: our electric bill last month was negative. Even with charging Scarlett and running the AC in the house. Our environmental impacts are also much lower by not using as much electricity (we are an all-electric house). We are using no fossil fuels. We live in an area where much of our errands can be done on foot. I bike to work every day. We only have one car (which reduces our monthly costs for fuel, insurance, maintenance, etc).

Back to the batteries. All indications are that the Tesla batteries will outlast the car.  If Scarlett’s  doesn’t hold at least 70% of a charge by the end of 8 years or 120,000 miles, it will be replaced under warranty. So replacing the battery is probably not in the cards.

Assuming the car goes away at the end of its life, I’ve been hearing of people tossing around the idea of using the battery as a home battery to supplement their solar. This would give it many more years of use.

In short, the carbon footprint of EV batteries and, for that matter, EVs in general, is far better then ICE vehicles.