Charging Your Electric Car At Night May Be Bad For The Environment

Jeremy Michalek, a professor of engineering and public policy and mechanical engineering at CMU, and his colleagues modeled the grid that supplies Washington, Philadelphia, Pittsburgh, Cincinnati and Chicago. “We looked at how power plant operations would change in response to electric vehicle charging load, and we modeled emissions from those plants and their downwind air pollution consequences for human health and the environment,” Michalek explained. “We found that charging [an electric car] late at night reduces power generation costs by a quarter to a third, largely by shifting to cheaper coal-fired power plants. But the extra emissions released as a result can cause 50 percent higher costs to human health and the environment.”