Written by IGCSEPhysics Content Team · Physics subject adviser: K. S. Tan, 15+ years teaching IGCSE Physics · Checked against the Cambridge IGCSE Physics (0625) 2026 to 2028 syllabus
Every energy source has environmental consequences. The key is to compare them fairly, considering the full life cycle.
Fossil fuels (coal, oil, natural gas)
- Release CO when burned, contributing to global warming and climate change.
- Coal and oil also release SO (acid rain) and particulates (respiratory health issues).
- Natural gas produces less CO per unit of energy than coal or oil.
- Mining and drilling damage habitats. Oil spills pollute oceans.
- Non-renewable: finite reserves will eventually run out.
Nuclear energy
- No CO during operation (very low carbon).
- Produces radioactive waste that remains hazardous for thousands of years and requires secure storage.
- Risk of nuclear accidents (Chernobyl, Fukushima), though statistically rare.
- Uranium is non-renewable but available in large quantities.
- Decommissioning old plants is expensive.
Renewable sources
| Source | Environmental impact |
|---|---|
| Wind | Visual impact, noise, bird strikes. No emissions during operation. |
| Solar | Large land area needed. Manufacturing panels uses energy and materials. |
| Hydroelectric | Flooding valleys destroys habitats. Dams disrupt river ecosystems. |
| Tidal | Disrupts coastal habitats. High construction cost. |
| Geothermal | Minimal surface impact. Only available in volcanic regions. |
| Biomass | Carbon-neutral in theory (CO absorbed = CO released). Competes with food crops for land. |
Common errors and how to correct them
- Saying renewables have “no environmental impact.” All energy sources affect the environment.
- Confusing renewable with clean. Biomass is renewable but still produces emissions.
How to apply this in an exam
Name the specific pollutants or impacts for each source. Compare fairly by considering reliability, carbon emissions, waste and land use.
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