Across
- 5. nuclei of small atoms combine
- 7. temperature differences in ocean water to produce electricity
- 8. the nucleus of a heavy atom splits
- 10. energy from sources that are constantly being formed
- 11. the use of sunlight to heat buildings directly
- 12. a devices that converst mechanical energy into electrical energy
- 14. used widely as a fuel source
- 15. energy that does not come from fossil fuels
- 16. electrical energy produced by the flow of water
- 18. formed from the remains of organisms that lived long ago
Down
- 1. energy used to heat water or heat a building
- 2. a devices that produce electricity by combining hydrogen adn oxygen
- 3. deposits that are discovered and are in commercial production
- 4. energy released by a fission or fusion reaction
- 6. process of saving energy
- 9. the percentage of energy put into a system
- 13. energy produced by heat within the earth
- 17. plant materia, manure, and other organic matter used as an energy source