Thermal coal: Impact on nature

The dirtiest kilowatt-hour, from the mine to the chimney

What this tab covers What taking energy from this source does to land, water, air and climate, wildlife and ecosystems, with life-cycle emissions and land use where measured.

Coal has the highest climate impact per unit of electricity of any major source, and its mining disturbs land, water and air through methane, dust, tailings and subsidence.

Life-cycle emissions 820 (range 740 to 910); UNECE gives 751 to 1,095 g CO2e/kWh¹² Life-cycle, pulverised coal power. IPCC AR5 median and range; UNECE (2022) range from IGCC in the US (low) to pulverised coal in China (high). With CCS: 190 to 250 for pulverised coal (AR5) or 147 to 469 (UNECE). Land use about 1,000 ha per TWh per year (median, life-cycle)¹⁰

Effects on nature

Area	Effect	Size	How it is reduced
Climate (combustion)	Burning coal emits more CO2 per unit of heat than any other common fuel.¹	94.6 t CO2/TJ for bituminous coal, 101 t for lignite and 106 t for peat, against 56.1 t for natural gas	Higher-efficiency plants, carbon capture and storage, fuel switching, retirement
Climate (methane from mines)	Methane trapped in coal seams escapes during and after mining, including from closed mines.⁸	More than 40 Mt CH4 in 2024, including nearly 5 Mt from abandoned mines	Drainage and capture of mine gas, ventilation-air oxidation, flooding or sealing closed mines
Land	Surface mines strip overburden across large areas. Underground mining can cause subsidence.¹⁰	Median about 1,000 ha per TWh per year of electricity	Progressive backfilling and reclamation
Water	Steam power plants evaporate cooling water. Mine tailings leach nutrients and metals.¹¹	0.90 to 5.9 L/kWh dissipated in steam plants; tailings release 600 to 800 g phosphorus-equivalent per MWh	Dry or hybrid cooling, lined tailings storage, water treatment
Human health and toxicity	Arsenic leaching from landfilled mining tailings drives coal's high human-toxicity score. Coal mining and combustion also release radon.¹¹	Coal has the highest non-carcinogenic toxicity score among the electricity sources assessed	Tailings management, flue-gas cleaning (particulates, SO2, NOx)
Mitigation potential (energy-sector methane)	Much of the methane from coal, oil and gas could be cut with known methods.⁹	About 70% of energy-sector methane avoidable with existing technologies; abandoned coal mines and oil and gas wells together emitted about 8 Mt	Mine-gas capture, leak detection and repair, ending routine venting

Combustion dominates coal's footprint. About 760 of the 820 g CO2e/kWh median is emitted at the stack, and the rest comes mostly from mining and methane. The UNECE range is wider because it includes old, inefficient plants and Chinese supply chains. Peat is the most carbon-intensive per unit of heat, and draining peatlands to harvest it also releases carbon stored in the remaining bog.

About 70% of energy-sector methane could be avoided with existing technologies, according to the IEA. For local air, modern flue-gas cleaning removes most particulates, sulphur dioxide and nitrogen oxides, but much of the world's coal fleet still runs with weaker controls.

Sources

2006 IPCC Guidelines for National Greenhouse Gas Inventories, Vol. 2 Energy, Ch. 1 Introduction (Tables 1.2 and 1.4) IPCC, 2006
Global Methane Tracker 2025: Understanding methane emissions IEA, 2025
Methane data and transparency continue to improve, but emissions remain far too high IEA, 2025
What are the land-use intensities of different energy sources? (summary of Lovering et al., PLoS ONE 2022) Breakthrough Institute, 2022
Carbon Neutrality in the UNECE Region: Integrated Life-cycle Assessment of Electricity Sources (ECE/ENERGY/141) UNECE, 2022
Climate Change 2014: Mitigation, Annex III Technology-specific cost and performance parameters (Table A.III.2) IPCC AR5 Working Group III, 2014