Energy-saving device making use of solar heat

The invention discloses an energy-saving device making use of solar heat. The device includes a mobile lifting mechanism and a solar thermal utilization mechanism. The solar thermal utilization mechanism is installed on the mobile lifting mechanism obliquely to the horizontal plane, and the mobile lifting mechanism drives the solar thermal utilization mechanism to move up and down. The solar thermal utilization mechanism includes a plurality of solar thermal utilization modules, a formwork supporting frame, a first driving device, a first rotating shaft, a second rotating shaft and a pluralityof gear transmission mechanisms. The number of the gear transmission mechanisms is the same as the number of the solar thermal utilization mechanism. The first driving device drives the second rotating shaft to rotate, the second rotating shaft drives the gear transmission mechanisms to rotate, and the gear transmission mechanisms drive the first rotating shaft to rotate, to make the solar thermal utilization mechanism r