At lighthouses，offshore fixed lights and lighted buoys where commercial electricity is not available，the power source depends on diesel generators and batteries． Various problems are involved in the transportation of fuel and batteries．
Therefore，energy derived from the wind，waves and sunshine have been used as the energy source for aids to navigation．
In 1934，at an offshore fixed light，a light of 14.5 w from a solar cell apparatus was the first case where a natural energy source was applied．Today，solar cell apparatus of a maximum capacity of 1 kw are equipped at lighthouses．

The first wave activated generator gave a light of lO w，but at present, lights of 100 w are in use．
Recently，a hybrid system of combining the solar generator and the wind activated generator，and the solar generator and the wave activated generator has been introduced．
To apply the use of energy derived from the wind，waves and sunshine is a favorable system for aids to navigation from the environmental point of view．