In the U.S., the major energy sources are petroleum oil, natural gas, coal, nuclear, and renewable energy. Electricity is a secondary energy that is generated from these energy forms.
Residential and commercial buildings, transportation, industry, and electric-powered generators consumer the most energy.
In 2011, the U.S. used 97.5 quadrillion British thermal units (Btu) of energy. Petroleum, natural gas, and coal were the most used sources, respectively.
Nuclear energy played little to no role in electricity generation 50 years ago, but in 2011, provided more than 20 percent of the energy used to generate America’s electricity.
Petroleum oil provided 18 percent of energy for electricity in 1973 and less than 1 percent in 2011.
In the U.S., electricity plants use more than 900 million short tons of coal to produce 40 percent of America’s electricity every year.
The use of coal emits sulfur dioxide, nitrogen oxide, heavy metals, carbon dioxide, and acid gases which are linked to acid rain, smog, global warming, and health issues.
In 2011, coal was the second highest cause of energy-related carbon emissions. Petroleum ranked first with 42 percent, coal had 34 percent, and natural gas emitted 24 percent of the energy-related carbon dioxide.
If energy efficiency doubles as planned by 2030, America will save $327 billion across buildings, transportation, industry, household, and taxable energy costs.
The amount of money that doubly efficient energy would save could pay off the existing debt in every household in the U.S.
The price the environment suffers from excessive energy use would also see relief. With the energy efficiency America is striving for, the U.S. carbon dioxide emissions would decrease by 4 billion metric tons.