Why the U.S. Uses Only Half of Its Grid Capacity

The United States electric grid operates at roughly half its capacity on average, a gap that a coalition backed by Google, Tesla, and Carrier argues can be closed with existing technologies to meet rising demand without massive new construction. Ian Magruder, founder of the Washington, D.C.-based nonprofit Utilize Coalition, said most studies place average grid utilization rates between 40 and 55 percent across different geographies [1]. The grid is built to meet peak demand, which in many regions occurs only a few days each year [1]. "We have to ensure that on the hottest summer day or the coldest winter morning we have enough power," Magruder told IEEE Spectrum [1]. The U.S. portion of the North American grid had a nameplate capacity of 1,280 gigawatts and produced 4,029 terawatt-hours in 2023, using 34 percent of primary energy to do so [3]. Over the last 20 years, the gap between average use and peak use has widened [1]. Grid operators have grown more conservative following major blackouts and reliability events, and the integration of variable-generation sources such as wind and solar has prompted operators to build in additional capacity [1]. Electrical grids consist of power stations, substations, transmission lines, and distribution networks that deliver electricity from producers to consumers [2]. Magruder pointed to several technologies that can increase utilization. Pairing battery storage with generation, managed electric vehicle charging, smart thermostats, and transmission technologies that safely maximize current in power lines are all part of the solution [1]. Demand flexibility, in which utility customers adapt their power use during peak hours, is also being explored, including work around flexible data centers [1]. Electric vehicles, which can be recharged from the grid, have seen technological advances in lithium batteries that have made them more feasible for the consumer market since the 2010s [4]. Utilize Coalition released a report earlier this year showing that a 10 percent increase in grid utilization could save Americans over US $100 billion over the next decade [1]. Magruder said electricity rates have risen and the coalition attributes that trend to declining utilization [1]. The phenomenon is global, though it varies by country. European grids face similar dynamics, and in some places utilization is even lower, while Australia and the United Kingdom are further ahead in measuring and managing utilization with new technologies [1].