Fossil fuels and nuclear are non-renewable
A non-renewable resource is finite -- it cannot be replenished within a human lifetime. Fossil fuels (coal, oil, natural gas) formed from ancient organisms over millions of years and are burned for energy, emitting CO2 and pollutants. Nuclear power splits uranium atoms (fission) for heat; uranium is a MINED, finite mineral, so nuclear is non-renewable despite low emissions. (Full grid in the note.)
Renewable resources, including HEP
A renewable resource is naturally replenished within a human lifetime: HEP, solar, wind, geothermal, tidal and biomass. HEP dams a river to spin turbines -- reliable low-carbon output, but very high build cost, and its reservoir floods land, displacing people and habitats. Each renewable has a limit: solar/wind are intermittent; geothermal needs shallow hot rock; tidal needs a large tidal range. All share HIGH install cost, LOW running cost (no fuel).
Fuelwood, energy mix and the energy gap
Fuelwood (burned directly for cooking/heating) is still the main energy source for many in developing countries. Heavy reliance causes deforestation and soil erosion, an unpaid collection burden (usually women and children), and indoor air pollution. A country's energy MIX is the sources it uses; demand rises with population, industry and living standards. When demand exceeds secure supply it faces an energy GAP; SECURITY means meeting demand from a diverse mix.
Drawn from real examiner reports.
Fuelwood is not a cost-free resource
Fuelwood has no cash price, breeding the idea it is genuinely "free" with no downside. It is not. Real, hidden costs: deforestation and soil erosion; indoor air pollution causing respiratory illness; and a heavy collection-time burden, usually unpaid and on women and children. Treat "no cash price" as very different from "no cost".
Nuclear is NOT renewable
The sharpest definition trap. Nuclear power burns no fossil fuel, so many wrongly call it "renewable". Classification depends on whether the FUEL is finite, not on emissions: uranium is a finite mined mineral, so nuclear is NON-RENEWABLE, alongside coal, oil and gas. Renewable = naturally replenished; non-renewable = finite (fossil fuels AND nuclear).
Digest (## 3.5 Energy): renewable vs non-renewable classification is genuinely difficult -- nuclear power is repeatedly and wrongly classified as renewable. (s22 Paper 12 Q6(a)(iii); w22 Paper 12 Q6(a)(iii))
"Clean/green" is not a full reason
Explaining the shift to renewables, candidates over-weight vague words ("clean", "green") and leave out economics. Give BOTH. Environmental: reduced CO2 (less global warming) and less pollution. Economic, often missed: falling technology cost; less reliance on imported fossil fuels; subsidies/targets. "Clean" alone, without saying WHAT is reduced, is too vague.
Digest (## 3.5 Energy): explaining the shift toward renewables, candidates over-weight environmental factors ("clean", "green") and under-weight economic drivers. (w22 Paper 12 Q6(a)(iv))
Installation cost ≠ running cost
Reasons a country avoids solar or wind must be precise on two counts. First, high INSTALLATION cost is NOT running cost -- running cost is low, as there is no fuel to buy; conflating them loses marks. Second, "climate" alone is too vague: name the limiting factor -- too little strong, direct sunshine for solar, or insufficiently strong/reliable wind.
Digest (## 3.5 Energy): reasons countries avoid solar/wind -- installation cost is conflated with ongoing running cost, and "climate" is cited without specifying the limiting factor. (w22 Paper 23 Q5(b))
Give precise nuclear disadvantages
Vague nuclear disadvantages ("danger of explosion", "air pollution") score little. Precise ones: the risk of a RADIATION LEAK; the high cost of DECOMMISSIONING a station; and storing radioactive waste for thousands of years. A real accident (e.g. Chernobyl, 1986) counts only if LINKED to why it deters governments -- public opposition, high safety costs.
Digest (## 3.3 Industry, concerning nuclear power): nuclear-power disadvantage answers stay imprecise ("danger of explosion", generic "air pollution") rather than precise (radiation leak, decommissioning cost); Chernobyl-type examples are cited without linking to WHY this deters governments. (s23 Paper 12 Q6(a)(iv))
Renewable ≠ constant/reliable
Renewable does not mean always-available. Solar and wind are INTERMITTENT -- solar gives nothing at night; wind needs strong, reliable speeds -- so alone they cannot guarantee constant (baseload) supply. HEP, geothermal and tidal CAN supply steadily where conditions allow. Do not claim a country runs wholly on solar or wind without storage or backup.
Energy supply vs energy demand
Keep these apart. SUPPLY is the energy a country produces or can access. DEMAND is what its population and industry need, rising with population, industry and living standards. An energy GAP appears where demand outstrips secure supply -- answers often describe rising demand but forget supply has not kept pace. A shortage is the RELATIONSHIP between the two.
Renewable does not mean impact-free
Renewable does NOT mean harm-free. A large HEP dam floods a wide area, displacing people and destroying farmland and habitat, and disrupting downstream flow. Wind turbines can be noisy and intrusive. "Clean" refers only to low emissions DURING operation -- not construction or land use. Weigh the low-carbon benefit against real build and land-use costs.
Digest (## Cross-cutting exam technique): vague terms such as "clean"/"green" recur as a credit-blocker -- they describe only low operating emissions, not overall impact. (all four sittings, Paper 1 key messages)
Level 3 on the 7-mark HEP case study
The HEP 7-marker rewards place detail plus balance. Top band: name a REAL scheme (e.g. the Three Gorges Dam, Yangtze, China), and cover BOTH an advantage (reliable, low-carbon power; flood control) AND a disadvantage (over a million resettled; farmland and habitat lost).
Classify the source before you judge
Many energy questions hinge on classifying the source -- renewable vs non-renewable. Get this right before judging: mislabelling nuclear as renewable wrecks every later point. State the source's correct category and one defining feature, then build your answer on that.
Compare energy sources, don't list them
"Compare" needs explicit comparative links, not two separate descriptions -- use higher/lower, greater, whereas. Figures side by side are not a comparison until a comparative word joins them. Structure by POINT (cost, emissions, reliability), covering both sources on each.
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