The EPA's new Greenhouse Gas Calculator helps turn greenhouse-gas savings into more easily understood everyday terms.

The calculator converts greenhouse-gas savings estimates - typically presented in million metric tons of carbon dioxide equivalents - into familiar terms from which emissions would result, such as:

- Driving a particular number of cars for a year;

- Using a particular amount of gasoline or barrels of oil;

- Using a particular number of tanker trucks' worth of gasoline;

- Providing energy to a particular number of homes for a year;

- Growing trees across a particular number of acres for a year;

- Recycling a particular quantity of waste instead of sending it to the landfill;

- Generating electricity from a particular number of coal fired power plants for a year.

Users can enter savings in emissions, electricity consumption, gallons of gasoline, or number of vehicles into the calculator and determine up to 13 different ways to express the magnitude of the savings. The calculator uses the latest emission factors, approaches and statistics available through 2007.

For example, if a typical household switched all its incandescent light bulbs to compact fluorescent ones, it would save about 75 percent of the lighting electricity use - or about 1,463 kilowatt hours a year.