In the industrialized world we don't see much coal, so it may not seem to figure in our everyday lives. But think again. Our world runs on electrical power, and much of that power comes from coal. In fact, coal provides, on average, 40 percent of the world's electrical energy.
Our dependence on coal is threatening potentially disastrous consequences for climate. Why? Because coal releases much more CO2 for each unit of energy produced than other fossil fuels. For instance, coal emits about 1.8 times the CO2 of natural gas, and 1.3 times that of oil. In the U.S. alone, CO2 emissions from coal totaled more than 2 billion metric tons in 2006.
What can you do with one metric ton of coal?
One metric ton of coal generates about 2,200 kilowatt hours (kWh) of electricity. That means ...
1 ton of coal can:
- ... meet the electricity needs of an average U.S. household for about two months
- ... illuminate 22,000 100-watt light bulbs for an hour
- ... run an electric water heater for about 6 months
- ... run a refrigerator for about 2 years
- ... feed a large power plant for about 13 seconds
- ... produce about 2.5 metric tons of CO2
What's the difference between energy and power?
Energy is the ability to do work. Power is the rate at which work is performed.
What's a watt?
A watt is a unit of power. It's equal to one joule (jool) of energy per second. A kilowatt is 1,000 watts, and a kilowatt hour is 1,000 watts delivered for an hour.