It is a successful trial solar process heating near a Government location in Shandong. Solar selective coating steel tubes are sealed inside glass pipe, with a pump working for a vacuum space between solar coated tube and glass pipe.

NB/T 10415-2020 is a new China standard issued at Oct.23rd 2020 for an official definition to parabolic trough receiver: Glass-metal sealed direct connection evacuated solar collector tube for medium temperature.