What happens when millions of electric vehicles meet the U.S. grid? by Bob Waterstripe Electricity consumption in the US is enormous, over 4 trillion kilowatt-hours (kWh) last year. That’s 12,068 kWh for every one of about 334 million Americans including little babies, enough power for each one of us to run a 1,500-Watt electric space heater 22 hours a day for 365 days. Or to drive a Tesla Model 3 for 50,200 miles (kids can use the autopilot feature). Today there are over 2 million electric vehicles (EVs) driving around the U.S., consuming some 7.2 billion kWh, or 0.18% of the electricity used last year in America. At that rate, it would take over 10 million EVs to use only 1% of that electricity. So what happens when we plug 10 million EVs into the grid? Not much — yet. However, there are over 280 million fossil-fuel burning cars, SUVs, and pickups in the U.S. today. 18 million such vehicles are sold in the U.S. in a good year. Now, with major automakers committing to 100% EV production in coming years, we will soon see millions and then tens of millions more EVs tapping the grid each year. Still, 18 million EV’s would still use only about 1.6% of that 2020 electricity At 18 million new EVs per year, we could replace all those 280 million vehicles with EVs in less than 16 years. 280 million EVs would use 25% of all the electricity we had in 2020. The good news — for now — is that the grid is built to handle peak power demand, normally in the hottest and coldest mornings, during business hours, and in early evenings. The rest of the time, demand for electricity is lower, so there is plenty of excess capacity for EVs if we charge them at night. This situation can hold us long enough to replace fossil fuel plants with renewables and batteries, and to build the additional clean power generation capacity we will need. Total utility-scale power generating capacity in the U.S. today is about 1.12 billion kW. Theoretically this capacity could generate overall more than twice the total electricity that we use today, although in many areas hot or cold weather can already strain the grid during peak hours. The ratio of peak demand to average demand is some 1.7 to 1.9, depending on the area. In fact, we would only need about 10% of that extra capacity for even 280 million EVs charging at night. The U.S. Energy Information Administration (EIA) predicts 2 that electricity demand will grow by less than 1% per year from now until 2050. However, even only 1% annual growth compounds to 35% more demand by 2050. This prediction does not allow for much growth of EVs and says that electricity used for transportation (EVs) will remain below 3% of total electricity demand even in 2050. Released in February, 2021, this otherwise brilliant analysis of our overall energy situation does not contemplate the now- inevitable rapid adoption of EVs. Besides building 35% additional generating capacity needed by 2050, or more for all those EVs, we also need to replace existing fossil fuel sources that account for 66% of our power today (20% coal, 43% natural gas, 3% oil) with clean solar and wind. Today, renewables deliver 25% (16% non-hydroelectric, 9% hydro-) and nuclear provides 9% of our total power. I conclude that one way or another the existing grid can power as many EVs as we can build, while we convert our electricity output to zero-carbon and add capacity for the future. People in most areas can take advantage of the economic and environmental benefits of EVs as fast as they are produced. As for building a zero-emission grid, the fastest way to add clean power is solar. The cheapest way to add clean power is rooftop solar on homes, businesses, and carports. This is called “distributed generation”. When a utility goes solar, the customers pay for the solar power plant, then they pay for the power forever. When you add solar to your home or other building, you pay once and get decades of free energy in return. If you have enough solar to cover the needs of the home and your EVs, too, this can amount to hundreds of thousands of dollars in long-term cash savings. Using solar to offset your home’s electric bill is great, but the same amount of solar eliminates more emissions, and saves a lot more money, when you power your EVs and avoid the emissions and the cost of burning gasoline or diesel. References: https://www.eia.gov/outlooks/aeo/pdf/A EO_Narrative_2021.pdf https://www.eia.gov/energyexplained/el ectricity/electricity-in-the-us-generation- capacity-and-sales.php