QUESTION: How much of an environmental problem will the batteries in alternative fuel cars create? Are they really a sound environmental alternative? Asked by Lynnae Thandiwe, Atlanta, Ga.
ANSWER: Recent chatter about Tesla’s electric sedan and Nissan’s reasonably priced electric compact car has made it easy to feel excited again about alternative fuel. The electric car may have met an untimely death circa 2006, but five years later, the tables are turning. Hybrid sales are up, and family-appropriate electric vehicle options are on the horizon.
But as appealing as alternative fuel cars may be to the conscientious consumer, you raise a valid question: we need to see the whole picture and consider the environmental impacts of changing the way we power cars. Is the impact of producing batteries worth the gas pumping-impacts that electric cars avoid? In short, the answer is yes, but it’s worth examining in more detail.
The environmental impacts of batteries are determined using life cycle analysis (LCA), a broad assessment considering all factors influencing creation, use, and disposal of a product, also discussed in depth in a recent SAGE column. For the lithium-ion batteries used in electric vehicles, an LCA quantifying the environmental impacts includes mining the metals used, manufacturing the various battery parts and, finally, assembly. While the final impacts of producing an electric vehicle prove to be higher than those associated with producing conventional car, when evaluated over the car’s expected lifetime — 90,000 miles — the electric vehicle’s impacts drop significantly below those of its conventional counterpart. Check out the Nitty Gritty answer for calculation details.
Existing LCAs, while valuable in aggregating most associated impacts, ignore a key stage of the battery’s lifecycle: the potential to repurpose used batteries that can no longer carry vehicles long distances. Elaine Chang, a Stanford alumna working for electric vehicle service provider, Better Place, is optimistic about battery reuse, partly because vehicles’ extremely high energy demand renders only mildly worn batteries nonfunctional. Once batteries decline to 80-percent capacity, industry standards consider them obsolete. The high remaining capacity on these discards, however, makes them ideal for reuse.
Incorporating these batteries into the electricity grid as storage is one potential new use. Because renewable energy resources like wind and solar operate on a natural schedule indifferent to electricity demand, extra demand is often filled in with electricity generated from fossil fuel power plants. To increase the share of renewables in our electricity mix, more storage might be necessary—a battery use that increases its lifecycle and decreases its environmental impact. Another potential reuse could be installing used batteries into vehicles that will not travel long distances and therefore not need full battery capacity.
Chang also notes, “Ninety-five to 100 percent of the battery can be recycled, but it might be at [an economic] cost.” Are we willing to bear this cost for the promise of a greener future? While the electric vehicle is not the cheapest way to get around, with battery recycling programs in place, it is certainly greener than the alternative. Chang is optimistic, saying, “Recycling will become a reality.”
The future of electric cars follows a promising storyline. Given the choice between purchasing a new internal combustion car or electric car, the electric option is the more environmentally friendly purchase. The added possibility of recycling batteries makes the electric vehicle an increasingly green choice. We think it’s time to get electric: get ready for an exciting ride.