Energy Efficiency

Within the context of sustainable design, energy efficiency is regarded as an important key to reducing fossil fuel use by improving the energy performance of equipment and appliances, buildings, and municipal infrastructure. Many energy experts today regard continued dependence on coal, oil, and natural gas to be unsustainable because supplies are not limitless and combustion of fossil fuels results in a variety of negative environmental impacts including air and water pollution and significant carbon dioxide emissions.

Energy efficiency describes the rate at which energy is used to accomplish a particular task (e.g., the miles that a car can travel per gallon of gasoline). Improving energy efficiency means getting more work from the same or less energy input. A hybrid sedan is more energy efficient than a large pick-up truck because it will travel farther on the same amount of gas.

Houses designed for a specific site, like this solar-heated, cement house built into a hillside, can employ topography and the path of the sun to increase efficiency

Source: iStockphoto

Improvement of energy efficiency has traditionally been considered a production engineering strategy that increased profits by reducing fuel costs. Improvement of the energy efficiency of equipment and machinery played a key role in the phenomenal growth of industrial productivity in the early 20th century. Since the oil embargo of the 1970s, federal, state, and utility programs have laid a solid foundation for improving the efficiency of energy consumption across all sectors of the economy. However, the new sense of urgency surrounding carbon emissions and other environmental impacts has led cities to identify and support the many opportunities that remain to improve energy efficiency in homes, businesses, schools, government buildings, and industrial facilities.