Environmental Protection Agency chief Gina McCarthy said on Thursday that newly proposed rules to slash carbon emissions from U.S. power plants will cut electricity bills after 2030 by forcing power plants to become more efficient. Speaking at a forum on energy efficiency in Washington, which she likened to "preaching to the choir," McCarthy took issue with critics' claims that the EPA's clean power plan will cause consumer electricity prices to skyrocket, in part by forcing older coal-fired plants to close. The rule, subject to a 120-day comment period, will steer investment toward renewable energy and energy efficiency companies, she said.