The United States and Canada are both developed countries. China and India are projected to have the greatest growth in energy consumption between 2006 and 2030.

The United States and Canada are both developed countries. China and India are projected to have the greatest growth in energy consumption between 2006 and 2030.

All of the above are emitted by vehicles running on gasoline and diesel fuel.

All of the above are emitted by vehicles running on gasoline and diesel fuel.

All of the above are emitted by vehicles running on gasoline and diesel fuel.

All of the above are emitted by vehicles running on gasoline and diesel fuel.

Worldwide consumption of energy sources is projected to rise by nearly 50% between 2006 and 2030.

Worldwide consumption of energy sources is projected to rise by nearly 50% between 2006 and 2030.

In the United States, the transportation sector releases the most CO2. In 2006, the transportation sector released nearly 2 billion metric tons of carbon dioxide, nearly all of which was from oil.

In the United States, the transportation sector releases the most CO2. In 2006, the transportation sector released nearly 2 billion metric tons of carbon dioxide, nearly all of which was from oil.

In the United States, the transportation sector releases the most CO2. In 2006, the transportation sector released nearly 2 billion metric tons of carbon dioxide, nearly all of which was from oil.

In 2008, 37% of the United States' total energy consumption came from oil, more than any other energy source.

In 2008, 37% of the United States' total energy consumption came from oil, more than any other energy source.

Out of all the renewable energy sources, biomass contributed the most to U.S. energy consumption in 2008.

Out of all the renewable energy sources, biomass contributed the most to U.S. energy consumption in 2008.

Out of all the renewable energy sources, biomass contributed the most to U.S. energy consumption in 2008.

Biofuels contain carbon and although they may burn “cleaner” than oil-derived fuels, they do not avoid generating carbon dioxide emissions.

Gasoline, diesel fuel, and natural gas all release CO2 when burned.

Gasoline, diesel fuel, and natural gas all release CO2 when burned.

Gasoline, diesel fuel, and natural gas all release CO2 when burned.

In 2005, a million Btu of energy from coal cost approximately $2, versus $5 for natural gas and $10 for oil. However, prices can fluctuate due to changes in the economy and new government policies.

In 2005, a million Btu of energy from coal cost approximately $2, versus $5 for natural gas and $10 for oil. However, prices can fluctuate due to changes in the economy and new government policies.