| A | B |
|---|
| heat energy in the Earth | Geothermal Energy |
| H-2 isotope of hydrogen | Deuterium |
| when two atomic nuclei fuse | Nuclear fusion |
| windmills used to generate electricity | Aerogenerators |
| can convert solar energy to electricity | PV Cells |
| windmill like an egg-beater | Darrieus rotor |
| many aerogenerators together | Wind farm |
| electricity produced by moving water | Hydroelectricity |
| solar energy is captured using collectors | Active solar energy |
| solar energy is capture naturally by a building | Passive solar energy |
| energy from the sun | Solar energy |
