While most fossil fuels in the United States are burned, or combusted, to produce heat and power, EIA estimates that the equivalent of about 5.5 quadrillion British thermal units of fossil fuels were consumed for non-combustion purposes in the United States in 2017. Over the past decade, non-combustion consumption of fossil fuels has typically accounted for about 7% of total fossil fuel consumption and about 6% of total energy consumption in the United States.