Across
- 4. Generated by moving water
- 5. renewable source that provides energy from tides
- 7. generated by tapping into underground reservoirs of hot water and steam
- 8. Produced by small-scale windmills or turbines
Down
- 1. created in the form of heat
- 2. Produced by photovoltaic cells/solar cells, also known as solar panels
- 3. generated by organic materials (biomass, biofuels, etc.)
- 4. a clean-burning fuel
- 6. uses electric generators placed on the ocean's surface