Electric Cars Would Save America Huge Amounts of Energy

An anonymous reader shares an opinion piece from Bloomberg, written by Liam Denning and Elaine He: Electrifying U.S. vehicles wipes out the equivalent of our entire current power demand. The U.S. consumes a lot of energy; last year, about 100 quadrillion BTUs (equivalent to 17 billion barrels of oil; which, we’ll admit, is only marginally less abstract). But only about a third of that is ultimately used in terms of actually lighting lights, turning wheels and so forth. The second law of thermodynamics means, for every unit of thermal energy we actually put to useful work, roughly another two end up wasted as heat. How we don’t use energy is just as important to understand as how we use it. Here’s a simplified version of a Sankey diagram from the Lawrence Livermore National Laboratory showing the various inputs to the U.S. energy system and where they end up. Large-scale waste is unavoidable with a thermal energy system, or one where we mostly burn stuff or split atoms (97% of the inputs in 2019). Burning fossil fuels also generates the carbon emissions causing climate change; so wasted energy is a proxy for the damage being done (apart from nuclear power). In contrast, renewables such as wind, solar and hydropower capture energy directly from infinite sources. While a small amount is lost in transmission, the vast majority is used. So here’s a thought experiment: What if the entire U.S. light-duty vehicle fleet (currently about 270 million cars and trucks) were electrified by 2030 and we expanded wind and solar generation at a rapid pace, while eliminating coal power, at the same time? The result is that we not only end up with a drop in U.S. carbon emissions of almost 30%, but also a far more efficient system overall.