Photo-voltaic safety de-energizing device

A safety mechanism for a solar cell group, the safety mechanism constituted of: a signal receiver arranged to assert a permissive signal indicative of reception by the signal receiver of a predetermined signal; an electronically controlled switch arranged to provide in a closed state an effective short circuit across the output of the solar cell group responsive to the absence of the asserted permissive signal of the signal receiver; and a power harvester in communication with the solar cell group and arranged to provide electric power to the signal receiver when the electronically controlled switch is the closed state.