Energy flow in a greenhouse equipped with glass raster lenses

A specially-equipped greenhouse has been evaluated by measuring the distribution of incident solar energy into heat, and vegetable and fish biomass production. The south-facing half of the roof of the solar greenhouse is equipped with a glass raster of linear Fresnel lenses (LFLs; see Jirka et al., same volume) which concentrate the heat energy from direct solar radiation in collectors while allowing diffuse light to pass through unhindered.