The invention relates to a biofilm based panel that is developed for reducing evaporation in dam reservoirs, and allows biomass production. The biofilm based panel of the invention comprises in general three main layers, a support layer (4), a nutrient layer (2) and a biofilm layer (1). Based on the climate in which the dams are located, a heat storage intermediate layer (3) may also be added. The support layer (4) is the top layer. The developed panel is positioned such that it partially covers the water surface.

The invention relates to a biofilm based panel that is developed for reducing evaporation in dam reservoirs, and allows biomass production. The biofilm based panel of the invention comprises in general three main layers, a support layer (4), a nutrient layer (2) and a biofilm layer (1). Based on the climate in which the dams are located, a heat storage intermediate layer (3) may also be added. The support layer (4) is the top layer. The developed panel is positioned such that it partially covers the water surface.