TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Module: In concentrated photovoltaic module, the cavity is dimensioned and shaped based upon the number of the one or more photovoltaic cells. The cavity is configured to provide a Lambertian distribution of concentrated solar radiation from the optical window to each of the one or more photovoltaic cells. It is coated with a high, diffuse reflectance material. The high, diffuse reflectance material comprises any of polytetrafluoroethylene, pressed magnesium oxide powder, and pressed barium sulfate powder. The base comprises a high, diffuse reflectance material, and where the cavity is formed in the base. The optical window is configured to receive concentrated solar radiation from a solar collector, where the concentrated solar radiation comprises concentration of at least hundreds of Suns. The cooling fluid is substantially optically transparent and non-electrically conductive. It comprises any of Germanium and Carbon tetrachloride. Preferred System: In concentrated photovoltaic system, the solar collector comprises a primary reflector; a secondary reflector configured to receive solar energy reflected from the primary reflector and concentrate the solar energy; and an opening in the primary reflector, where the concentrated solar energy is provided by the secondary reflector to the opening, where the primary reflector and the secondary reflector each comprise inflatable components, and where the concentrated photovoltaic module is disposed to the opening in the primary reflector; or the solar collector comprises a primary reflector; a transparent and flexible material disposed to the primary reflector, where the transparent and flexible material is substantially optically transparent in the infrared region; and where the primary reflector and the transparent and flexible material each comprise inflatable components, and where the concentrated photovoltaic module is disposed to the transparent and flexible material.