IB ESS SL 7.2.1 Energy source types Question Bank
Practise IB ESS SL/HL 7.2.1 by applying energy source types concepts to exam-style environmental systems questions.
- Syllabus
- First assessment 2026
- Course
- ESS SL
- Level
- SL
Practise IB ESS SL/HL 7.2.1 by applying energy source types concepts to exam-style environmental systems questions.
Outline the range of energy resources available to society.
Range:
e.g. renewability:
renewable energy resources are replenished within a similar time-scale to that at which they are extracted;
resources may be renewable through chemical fixation of solar energy / through direct use of solar heat/light/ quite independently of solar energy;
non-renewable energy resources cannot be replenished within a similar timescale to that at which they are extracted;
replenishable energy resources may be dependent on solar energy for replenishment but do not involve its chemical fixation (eg hydropower, 'solar' power, wind power, geothermal, tidal etc);
N.B. This last category of 'replenishable' is often included within 'renewable' energy resources in the literature, so do not penalise responses that do the same.
e.g. cost:
costs of energy resource may come from extraction, production, transport, storage, utilisation;
some have high set-up cost but low production cost, and vice versa;
there is economy of scale where cost can be reduced through centralisation;
cost can vary considerably dependent on time and location;
Examples:
Marking guidance:
Award [1 max] for each named example with some comment identifying its position within the chosen range. Appropriate comments may vary considerably but should be of equal validity, relevance and significance to those shown below:
biofuel/charcoal/fuelwood/biogas - is renewable replenished through solar energy/photosynthesis/has relatively low extraction/production costs/most readily available to rural ELDC communities;
hydroelectric energy - is renewable/replenishable dependent on solar energy / has high set- up but low maintenance cost / cost effectiveness highly dependent on location;
solar energy - is renewable/replenishable utilising light or heat of the sun / most direct renewable use of solar energy / high set-up costs but low maintenance / cost-effectiveness quite dependent on latitude/climate;
wind energy - is renewable/replenishable dependent on solar energy/extraction has no impact on its replenishment/relatively low cost but inconsistent production/adaptable for small or large scale production;
tidal energy - is renewable/replenishable but not dependent on solar energy/dependent on planetary rotation/gravity / fairly high installation cost but relatively low maintenance / limited to coastal location with sufficient tidal range;
geothermal energy is renewable/replenishable but not dependent on solar energy/replenished by heat from earth's core / can be relatively cheap but very dependent on location / recently become cost effective through technological development;
requires an underground/close to the surface heat source;
fossil fuels are non-renewable since their formation takes vast amounts of time compared to rates of extraction / although large reserves do still exist, stocks are depleting / cost will vary considerably dependent on a regions available reserves / cost of extraction very variable dependent on sources;
Other examples of energy sources with appropriate comments may be credited.
For full credit, a response should identify the RANGE over which energy sources are being considered and then identify the position within this range for a number of examples. The most obvious range might be their renewability, but responses that compare/identify sources over a range of relative cost/efficiency/availability/current consumption/current production etc should equally be credited.
Award 2 max for outlining the range, and 4 max for naming and correctly identifying the position of different energy resources within this range.