Patent ID: 8061077

Claim:
A cover element for greenhouses comprising: a panel-like element comprising a first substantially transparent layer comprising, first-strips that have optical means for deviating and concentrating light, and second strips that are optically neutral strips and that are alternated with the first strips, and a second partially opaque layer comprising, third strips that are optically neutral and substantially transparent, and fourth strips that are opaque strips and that are alternated with the third strips, the fourth strips comprising photovoltaic elements, wherein said first and said second layer layers overlap one over the other such that the fourth strips are disposed under the second strips, wherein the distance between the first and the second layers, the widths of the first and the third strips, and of the second and the fourth strips, are dimensioned such that an amount of solar light transmitted through the first and the second layers and the amount of the solar light falling on the fourth strips is modified as a function of an angle of incidence of the solar light and such that, when the sun is at a highest position above the horizon, a predetermined amount of light passes through the first and the second layers while a remaining amount of light is deviated by said optical means on said photovoltaic elements, and when the sun is at a lowest position above the horizon, a predetermined amount of light passes through the panel while a remaining amount of light is deviated by said first strips, and wherein the remaining amount of light when the sun is at the highest position is larger than the remaining amount of light when the sun is at the lowest position.