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