An electricity operator is comparing a tidal generator with a geothermal power station. The table shows their power outputs at different times during one day.
| Time | 00:00 | 04:00 | 08:00 | 12:00 | 16:00 | 20:00 | 24:00 |
|---|---|---|---|---|---|---|---|
| Power output from tidal generator in MW | 0 | 8 | 3 | 0 | 9 | 4 | 0 |
| Power output from geothermal power station in MW | 9 | 9 | 9 | 9 | 9 | 9 | 9 |
The operator makes this claim:
‘The output of the tidal generator can be forecast years in advance, so the tidal generator will provide a continuous supply.’
Evaluate the operator’s claim.
The demand for electricity is 12 MW at each time shown in the table. A gas power station supplies any difference between the demand and the combined output of the tidal generator and geothermal power station.
State all the times when the gas power station must generate electricity. Explain why a gas power station can be used in this way.
86 exam-style questions on AQA GCSE Physics 1.3 National and global energy resources, covering 1.3 National and global energy resources. Each one has a worked solution and a mark scheme showing where the marks go.