People Power: Turning Body Heat In To Energy

HOW CAN HOMES CONSERVE ENERGY? There are many ways in which houses can conserve energy. Improvements in energy-efficient lighting can reduce power usage by as much as 65 percent. In fact, if every American household changed just five of the most-used lighting fixtures to energy-efficient technology, they would save a total of $6 billion in costs and reduce power usage by the equivalent of the annual output of more than 21 power plants. Many homes have high-performance, energy-efficient windows -- featuring double glazing or special coatings -- to reduce heat loss in cooler climates and heat gain in warmer climates. These two factors account for 50 percent of a home's heating and cooling needs. Replacing window frames with low-conductance materials like wood, vinyl, and fiberglass can also improve a home's insulating capability.

ON THE GRID: The nation's power grid boasts more than 6,000 interconnected power generation stations. Power is sent around the country via half a million miles of bulk transmission lines carrying high voltage charges of electricity. From these lines, power is sent to regional and neighborhood substations, where the electricity is then stepped down from high voltage to a current suitable for use in homes and offices. The system has its advantages: distant stations can provide electricity to cities and towns that may have lost power. But unusually high or unbalanced demands for power -- especially those that develop suddenly -- can upset the smooth flow of electricity. This can cause a blackout in one section of a grid, or ripple through the entire grid, shutting down one section after another, making it difficult to restore power from neighboring stations.