A method to remove snow, frost and ice over an outdoor photovoltaic system having a front light-transmitting panel for sending said light to solar cells and opposed thereto, a rear being of a double wall construction, said double wall consisting of a first wall and a second wall, said first wall being in contact with the back of said solar cells to enable heat transfer, and said first wall on its side facing away from said solar cells being of a dark-opaque colour, solar-light-absorbing surface generating heat,
- said second wall being a light-transmitting enclosure of said dark-opaque coloured side of said first wall, but spaced therefrom so as to produce a greenhouse effect, comprising:
- maintaining said light-transmitting panel at an angle with the horizontal,
- receiving reflected solar rays from the surroundings of the photovoltaic systems through said light-transmitting enclosure to said dark-opaque coloured side of said first wall to be absorbed by said side and converted into heat to be transmitted to, and to raise the temperature of said light-transmitting panel, and simultaneously said light-transmitting enclosure creating a greenhouse effect and thereby an additional temperature increment to further raise the temperature of said light-transmitting panel, thereby,
- when said light-transmitting panel of said front is at, or above, the melting temperature of water, said panel causing any snow, frost, and ice present on said panel to form a water film on which any remaining snow, frost, and ice slide down,
- and when said light-transmitting panel of said front is below the melting temperature of water, said panel which has a temperature higher than ambient temperature, causing accelerated sublimation of any snow, frost, and ice present in frozen form on said panel.