Across
- 3. Certification for energy efficiency
- 5. Simultaneous production of electricity and useful heat
- 8. Fossil fuel extracted from underground
- 12. Using Earth's internal heat
- 13. Process of extracting oil or gas from shale rock
- 16. Structure for growing plants
- 17. Partially decayed plant matter used as fuel
- 20. Powered by moving air
- 21. Powered by water flow
- 23. Device that converts chemical energy into electricity
- 24. Element essential to life on Earth
- 29. Relating to atomic energy
- 31. Protection and preservation of natural resources
- 32. Production of energy
- 33. Use of natural light to illuminate indoor spaces
- 36. Release of gases into the atmosphere
- 37. Capacity for doing work
- 40. Use of resources
- 41. Rate at which work is done
- 43. Regulations for energy efficiency
- 45. Biofuel made from vegetable oils or animal fats
- 46. Mixture of sand, water, and oil
- 47. Fuels derived from biomass
- 48. Biofuel made from corn or other crops
- 49. Fossil fuel formed from plants
Down
- 1. Powered by the sun
- 2. Material used to prevent heat loss
- 4. Result or consequence
- 6. Element with potential as a clean fuel source
- 7. Advanced electricity distribution system
- 9. Form of energy produced by moving electrons
- 10. Relating to ocean waves
- 11. Organic matter used as fuel
- 14. Fossil fuel in gaseous form
- 15. Form of energy transfer
- 18. System that credits excess solar power back to the grid
- 19. Evaluation of energy use
- 22. Long-term weather patterns
- 25. System that converts solar energy into electricity
- 26. Relating to the tide
- 27. Non-renewable sources of energy
- 28. Type of electric vehicle
- 30. Measure of carbon emissions
- 34. Sedimentary rock that contains oil or gas
- 35. Process of becoming different
- 36. Vehicle powered by electricity
- 38. Ability to use resources effectively
- 39. Design that utilizes natural light and heat
- 42. Substance used for energy generation
- 44. Capable of being replenished