Across
- 2. Energy from sun
- 3. Power from water flow
- 5. Passive air movement
- 7. Eco-electric grid
- 9. Solar water system
- 12. Device to store energy
- 13. Natural gas from waste
- 14. Solar-powered light
Down
- 1. Panel collecting sunlight
- 4. Earth-based heating system
- 6. Energy from wind
- 8. Solar cell connector
- 10. Fuel-saving engine
- 11. Bio-fuel made from plants
- 15. Rooftop unit