Method of and building for growing plants

A greenhouse arrangement for growing plants comprising:

• a plurality of light filtering panels arranged to filter natural sunlight or artificial light to produce filtered light comprising wavelengths preferential for growth of a species of plant, each panel including a light transmissive substrate substantially transparent to natural sunlight or artificial light and a filter formed or supported on the substrate and arranged to filter the natural sunlight or artificial light to produce the filtered light;
• wherein at least some of the panels are provided with one or more PV cells along edges thereof and the panels are arranged to direct a portion of the natural sunlight or artificial light to one or more of the PV cells.

A greenhouse arrangement for growing plants comprising:

• a plurality of light filtering panels arranged to filter natural sunlight or artificial light to produce filtered light comprising wavelengths preferential for growth of a species of plant, each panel including a light transmissive substrate substantially transparent to natural sunlight or artificial light and a thin film filter formed or supported on the substrate and arranged to filter the natural sunlight or artificial light to produce the filtered light;
• wherein the thin film filter comprises 2N+1 layers where N is an integer ≥1 and the filter comprises a central layer and N layers on each side of the central layer.

A panel for a building comprising:

• a light transmissive substrate substantially transparent to natural sunlight or artificial light and a filter formed or supported on the substrate and arranged to filter the natural sunlight or artificial light to produce filtered light comprising selected wavelengths;
• wherein the filter comprises 2N+1 layers of material where N is an integer ≥1 and the filter comprises a central layer and N layers on each side of the central layer.

A panel for a building comprising:

• a light transmissive substrate substantially transparent to natural sunlight or artificial light and a filter formed or supported on the substrate and arranged to filter the natural sunlight or artificial light to produce filtered light comprising selected wavelengths;
• one or more PV cells along edges of the substrate;
• wherein the filter or another medium is arranged to direct a portion of the natural sunlight or artificial light to one or more of the PV cells.