science

4. any substance in nature that we use for energy
6. a fossil fuel in a gas form used for heating and electricity
7. the process by which two or more small nuclei fuse to make a bigger nucleus
8. electrical energy produced by the flow of falling water
9. a renewable resource that comes from the sun
12. a cell that generates electricity from a controlled reaction between hydrogen and oxygen
13. the process by which materials in the Earth's crust are taken from the Earth
16. a nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
18. energy from steam or hot water produced from hot or molten underground rocks
20. the practice of finding ways to use less energy or to use energy more efficiently
21. a nonrenewable resource that comes from within of atoms
22. electricity generated by the movement of sea water caused by the tides

1. oil deposits that has been discovered but remains unused in the ground and can be extracted profitably at current prices using current technology
2. a solid fossil fuel formed underground from buried decomposed plant material
3. nonrenewable resources in the Earth's crust, its made from the remains of ancient organisms
5. the use of technology to collect, store, and distribute the sun's energy
10. oily fossil fuel, also known as crude oil
11. energy source that comes from plant material, manure, and any other organic matter
14. a resource that cannot be replaced or takes a very long time to be replaced
15. the use of sunlight to heat buildings directly
17. a resource that can be replaced in a short time
19. power obtained by harnessing the energy of the wind through a windmill