of carbon entering the atmosphere combines with oxygen to form nearly four pounds of carbon dioxide, America's contribution to greenhouse gas build-up is even more striking. Taking a shower each morning produces 550 pounds of CO2 in a year. Using a computer 40 hours a week produces 600 pounds of CO2. Lighting an average house for a year emits 2,000 pounds. Lighting an large office building not surprisingly produces much more, 2.5 million pounds of CO2. And about one third of all American greenhouse emissions come from automobiles. JONATHAN G. KOOMEY: People drive, on average, about 12,000 miles per year, and a typical new car gets roughly 28 miles per gallon. That means that you will use about 430 gallons per year. And so over the course of a year, the person driving this new car will emit roughly 2,200 pounds of carbon per year. That's roughly the weight of the car itself. Now, if you have an SUV, which only gets 14 miles per gallon, you're emitting 4,400 pounds per year, essentially the same as having two cars on the road instead of one. NARRATOR: Apart from the energy we use to live, enormous amounts of power are required to manufacture all the things we buy. Grede Foundries in Minnesota needs as much electricity as a small town. And it needs this power on demand. WILLIAM NESTEL, Grede Foundries: Grede makes all steel and iron parts. We make the rear end for the Dodge pickup trucks, and we make