As political leaders gather in Washington and across the country in early 2007, energy will rank high on their agendas. Public concern about dependence on imported oil and the impending crisis of energy-induced climate change played a big role in November's elections — and voters won't put up with another year of complacent inaction.

While legislators contemplate alternatives to the fossil fuels we rely on so heavily today, they will find the answer all around them. In the near-term, saved energy is both more abundant and less expensive than any of the new energy sources that are attracting such attention in investment and policy circles today.

Improving energy efficiency represents the most immediate and often the most cost-effective way to reduce oil dependence, improve energy security and reduce the health and environmental impact of our energy system. By reducing the total energy requirements of the U.S. economy, improved energy efficiency will make increased reliance on renewable energy sources more practical and affordable.

Energy efficiency has played a critical role in the U.S. energy supply in recent decades, reducing total energy use per dollar of gross national product (GNP) by 49 percent since the 1970s. Compared to a 1973 baseline, America now saves more energy than it produces from any single source, including oil. Efficiency improvements stabilize energy prices by reducing demand, while also delivering the same services we value — whether hot showers or cold drinks — at lower cost.

The potential for additional energy savings is vast: U.S. energy use per dollar of GNP is nearly double that of other industrial countries. More than two-thirds of the fossil fuels consumed are lost as waste heat in power plants and motor vehicles.

The fuel economy of new U.S. motor vehicles advanced rapidly, from 14 miles-per-gallon (mpg) in the mid-1970s to 21 mpg in 1982, driven by rising fuel prices and government-mandated fuel economy standards. But in 2006, new U.S. vehicles still averaged just 21 mpg; for over two decades, automakers have put most of their engineering efforts into building larger vehicles with more powerful engines, offsetting the potential fuel economy gains from new technologies.

The time is ripe for another great leap in vehicle efficiency. New technologies such as hybrid drive trains, clean-burning diesel engines, continuously variable transmissions and lightweight materials could allow vehicle fuel economy to double over the next two decades.

Significant efficiency gains are also possible in the electricity sector. Americans spend $200 billion annually on electricity, but current demand could be halved with cost-effective technologies already available on the market. Furthermore, decreasing electricity demand reduces the need for new, large power plants, allowing smaller, distributed, renewable generation to play a greater role in meeting our energy needs.

Past experience demonstrates that strong government policies can spur the private sector to invest in efficiency improvements. Since national home appliance efficiency standards were enacted in 1987, manufacturers have achieved major savings in appliance energy use. Refrigerator efficiency nearly tripled between 1972 and 1999, and dishwasher efficiency has more than doubled in the last eight years.

California’s “Flex Your Power” campaign, enacted in response to the state’s 2001 energy crisis, immediately reduced power demand by 5,000 megawatts by replacing millions of standard light bulbs with compact fluorescent lights, installing light-emitting diode (LED) traffic lights, and replacing inefficient appliances. Because of robust efficiency policies, California has the lowest per-capita energy consumption in the nation, without sacrificing comfort or valued services.

Technologies available today could increase appliance efficiency by at least an additional 33 percent over the next decade, and further improvements in dryers, televisions, lighting and standby power consumption could avoid more than half of the projected growth in demand in the industrial world by 2030.

The integration of efficiency with renewable energy maximizes the benefits of both. For example, the correct building orientation can save up to 20 percent of heating costs; those savings can jump to 75 percent when renewable energy and appropriate insulation are integrated into the building.

A national commitment to improved efficiency can transition the U.S. energy economy in ways that will yield dividends for all Americans.

Christopher Flavin is president of the Worldwatch Institute. A portion of this commentary was reprinted from “American Energy: The Renewable Path to Energy Security.”  To access the entire report, visit www.AmericanEnergyNow.org.