Evacuated tubes convert solar energy into thermal energy that is transferred to copper U pipes by an aluminum fin with high solar energy absorption and low heat radiance loss. Liquid (pure water or glycol solution) in the U pipe heats up, and the U pipe conducts thermal energy to the water inside the storage tank through internal copper coils. Uses an electrical heater to heat water during cloudy days or at night. As the water temperature can be adjusted using an automatic controller, user can get hot water all day long. With a testing pressure of 12 MPa, this system has a working pressure of 0.6 MPa. Solar water heaters can still work even with several tubes broken. Highly efficient insulation with integrated polyurethane foam or rock wool.