Energy efficiency has met three-quarters of United States demand for new energy services since 1970, but it goes relatively unnoticed amid a focus on energy production, according to a new report from the American Council for an Energy-Efficient Economy (ACEEE). The report notes that the U.S. economy uses half as much energy per unit of economic output than it did back in 1970, making energy efficiency the “fastest-growing success story of the last 50 years.”

The report focuses specifically on 2004, when roughly $300 billion was invested in energy efficiency in the United States, supporting 1.6 million jobs. That investment was triple the amount invested in the energy supply infrastructure, and it generated 1.7 quadrillion Btu, or quads, of energy savings. For comparison, the United States currently consumes about 100 quads of energy. The 2004 savings were roughly equal to the combined energy output of 40 mid-sized coal-fired power plants. Nearly 60 percent of total energy efficiency investments were made in buildings, including homes, commercial buildings, and energy efficient devices, while about a quarter of the investments went toward industrial energy efficiency improvements. Only 11 percent of the investments went towards improving the fuel economy of cars, trucks, aircraft, and other forms of transportation, despite the fact that the transportation sector consumes 28 percent of the U.S. energy supply.

The ACEEE report also finds plenty of room for improvement, noting that the United States can reduce energy consumption by an additional 25-30 percent over the next quarter century through cost-effective energy efficiency measures. In an environment of accelerated market transformation and rapid growth in energy efficiency, the total annual investments in energy efficiency could approach $400 billion by 2030, according to the report.

To view an executive summary or the complete report,