Helping Business Help the Climate

The global push toward decarbonization is dramatically reshaping both supply and demand for electricity. On the supply side, fossil fuel generation is being replaced by wind and solar power, which generate only when wind and sun are available. On the demand side, natural gas heating and gasoline vehicles are being replaced by electric heat and electric vehicles, which are to be powered by new renewable generation. Between these two trends is a crucially important challenge and opportunity: making electricity demand more flexible, so that it can respond to variation in supply and avoid overloading the distribution grid.

Many analysts believe that managed charging of electric vehicles (EVs) may be the single biggest opportunity for electricity load management. EVs require significant amounts of electricity, and EV chargers can draw about ten times the average load of an American home. Currently, most drivers plug in their EV when they arrive at home in the early evening, and the car immediately charges for several hours and then sits idle until a morning trip. This “un-managed charging” imposes two costs. First, electricity generation has relatively high private and social costs in the early evening, as the sun goes down and fossil fuel power plants ramp up to compensate for the loss of solar power. Second, neighborhood-level electricity distribution infrastructure (e.g., transformers) wear out more quickly if demand increases further at peak times instead of evening out over time.

To reduce these costs, electric utilities are beginning to implement managed EV charging programs. In a managed charging program, EV owners are paid to install software that optimally charges all vehicles in a coordinated least-cost manner, subject to the constraint that each vehicle is fully charged by the time that the owner next needs to drive. WeaveGrid is a San Francisco-based company that is the U.S. leader in implementing managed charging programs for electric utilities. In partnership with WeaveGrid, our research team is working to evaluate and improve the effects of managed electric vehicle charging.