Energy Sources

1. the perceptible natural movement of the air, especially in the form of a current of air blowing from a particular direction.
3. the star around which the earth orbits.
5. a combustible black or dark brown rock consisting mainly of carbonized plant matter, found mainly in underground deposits and widely used as fuel.
8. a natural fuel such as coal or gas, formed in the geological past from the remains of living organisms.
10. a viscous liquid derived from petroleum, especially for use as a fuel or lubricant.
11. a fuel derived directly from living matter.
12. a source of energy that is not depleted by use, such as water, wind, or solar power.
14. of, relating to, or constituting a nucleus
15. the total quantity or weight of organisms in a given area or volume.

2. flammable gas, consisting largely of methane and other hydrocarbons, occurring naturally underground (often in association with petroleum) and used as fuel.
4. sources that will run out or will not be replenished in our lifetimes
6. a renewable source of energy that generates power by using a dam or diversion structure to alter the natural flow of a river or other body of water.
7. the sun's rays as a source of energy from which power for domestic or industrial use may be generated.
9. relating to or produced by the internal heat of the earth.
13. power derived from the utilization of physical or chemical resources, especially to provide light and heat or to work machines.