Solar collector

A solar collector comprising:

• a conduit for a working fluid, and a parabolic trough reflector arranged to focus reflected sunlight onto the conduit;
• wherein the parabolic trough reflector is arranged to pivot around the conduit;
• wherein the conduit comprises:
• an inner absorber tube for carrying the working fluid, and
• an outer transparent insulating tube surrounding the inner absorber tube, wherein the inner absorber tube and the outer transparent insulating tube are not fixed to each other;
• wherein the outer transparent insulating tube comprises a first outer transparent insulating tube wall, a second outer transparent insulating tube wall, and an at least partially evacuated space between the first outer transparent insulating tube wall and the second outer transparent insulating tube wall, wherein the solar collector further comprises:
• at least one bearing between the conduit and the parabolic trough reflector which allows the parabolic trough reflector to pivot around the conduit, and
• at least one stand which supports the conduit and is connected to the parabolic trough reflector by the at least one bearing,
• wherein the at least one bearing is an annular bearing comprising a central aperture through which the conduit extends and within which the conduit is supported, and
• wherein the at least one bearing comprises an inner portion with the central aperture, and the inner portion is fixed to the at least one stand.