Alternative Energy Sources

12345678910111213141516171819202122
Across
  1. 4. Extracting fossil fuels by removing soil and rock overlying the mineral deposit
  2. 8. Energy harnessed by the sun
  3. 9. An intergovernmental organization that focuses on transitioning into alternative energy sources
  4. 11. A system that maintains its own viability for continual use
  5. 13. Chemical reaction between two substances that gives off carbon dioxide
  6. 14. Energy harnessed from the flow of water
  7. 15. Release of harmful gasses into the atmosphere
  8. 16. A gas obtained from combustion of coal, natural gas, and oil
  9. 19. Energy harnessed from heat sources within the Earth's crust
  10. 21. An agency in the US responsible for creating green solutions and renewable energy sources
  11. 22. Deposits of tar that is turned into oil
Down
  1. 1. Harnessing energy through biological materials
  2. 2. Gases released into the atmosphere create this effect that traps the sun's warmth
  3. 3. Extracting coal from within the Earth
  4. 5. Harmful man-made substances and products in an environment
  5. 6. A machine used to harness wind energy
  6. 7. A unit of power used to measure electricity
  7. 10. A method for generating power using solar cells to convert energy from the sun into a flow of electrons
  8. 12. Combustible organic material derived from the remains of former life
  9. 15. Any source of usable power
  10. 17. Precipitation that contains acid-forming chemicals
  11. 18. A way to extract fossil fuels by fracturing rocks in the Earth's surface and injecting chemicals at a high pressure
  12. 20. Energy harnessed from ocean tides