Solar power

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Phipps kills an Ice Warrior with solar power. (DW: The Seeds of Death)

Solar power was the use of solar energy to generate electricity. While using Daniel Eldred's rocket, the Second Doctor, Zoe Heriot and Jamie McCrimmon were relying on a homing beam that functioned with solar power. When the solar power source was disabled, the rocket was left to float in space.

Phipps used a solar power generator to kill an Ice Warrior. (DW: The Seeds of Death)

Solar power