1. The vacuum tubes absorb the solar energy and transfer into the heat energy then pass to the U pipe, it can get high temperature.
2. The vacuum tubes heat pipe absorb the solar energy and transfer into the heat energy, then pass it to the U pipe.
3. There is no water in the vacuum tube, so the tube will not break in the winner.
4. It is steady and credible.
5. It can be combined with the architecture perfectly.
6. It can still operate in the event of casional tube breakage