Canada is a net exporter of oil, natural gas, coal, and electricity. It is one of the most important sources for U.S. energy imports. See the U.S. Energy Information Service country profile..
Canada has considerable natural resources and is one of the world’s largest producers and exporters of energy. In 2006, Canada produced 19.3 quadrillion British Thermal Units (Btu) of total energy, the fifth-largest amount in the world. Since 1980, Canada’s total energy production has increased by 87 percent, while its total energy consumption has increased by only 44 percent. Almost all of Canada’s energy exports go to the United States, making it the largest source of U.S. energy imports. Canada is consistently among the top sources for U.S. oil imports, and it is the largest source of U.S. natural gas and electricity imports.
See details.. http://www.eia.doe.gov/emeu/cabs/Canada/Full.html.