Example
Coal, petroleum and natural gas release carbon when combusted.
The catch
Upstream extraction and transport can create additional greenhouse gas emissions.
Related terms
Greenhouse gas, Electrification, Energy conservation, Energy efficiency, Energy storage, Heat pump
In more depth
Fossil fuel, explained.
Fossil fuel combustion is the largest source of human CO₂ emissions, and the fuels differ in how much CO₂ they release for the same energy. Coal releases the most, oil less and gas the least, but gas can lose much of that advantage when methane escapes between the well and the burner through fugitive emissions and venting.
The supply side deserves equal attention. UNEP's production gap reports find that governments plan to produce far more coal, oil and gas than is consistent with the 1.5°C goal. Each new field or mine is built to run for decades, so investment decisions made now lock in emissions well into the future.
In the journal