The utilization of energy for human purposes is a defining characteristic of industrial society. The conversion of energy from one form to another and the efficient production of mechanical work for heat energy has been studied and improved for...

Energy efficiency is a ratio of energy input to useful energy output, often expressed as a percentage. It measures how much energy of one kind is converted into usable energy of another kind. Incandescent light bulbs convert just 5 percent of the...

Energy efficiency is a measure of how much of the input energy is useful as output energy. An automobile, for example, typically has a low efficiency, around 30%, as much of the consumed fuel is converted to heat instead of power in the driveshaft. A...

Although energy efficiency was already heavily emphasized in the 1970s as a key strategy for energy security, more recently it has also been recognized as one of the most cost-effective strategies for reducing environmentally harmful emissions. Energy...

In physics and engineering, including mechanical and electrical engineering, energy efficiency is a dimensionless number, with a value between 0 and 1 or, when multiplied by 100, is given as a percentage. The energy efficiency of a process, denoted by...

Democratic presidential candidate John Edwards on Tuesday defended the construction of a sprawling, 28,000-square-foot house in North Carolina, arguing that his home is a model of energy efficiency."The house was built from the beginning, both in its location for passive solar and the use of...

The House voted Tuesday to award increases to programs aimed at making cars and buildings more energy efficient and boosting research and development of alternative energy sources.By a 312-111 vote, the House passed a $32 billion measure funding the Department of Energy budget and hundreds...

The energy efficiency of China's fuel-guzzling economy is improving but the country _ the world's No. 2 oil consumer _ is still struggling to meet self-imposed conservation targets, the government said Tuesday.China launched a five-year campaign in 2006 to cut energy use per unit of...

Los Angeles and Pittsburgh provide examples of what to do _ and not to do _ about China's severe air pollution in the face of surging energy use from rapid economic growth, U.S. and Chinese scientists say.The study released Thursday compared the world's two biggest...