Abstract: The present invention provides a solar heat collecting device having good heat collection efficiency. A uniaxial solar-tracking reflective mirror group is arranged such that each longitudinal axis thereof faces the same direction. A first biaxial solar-tracking reflective mirror group and a second biaxial solar-tracking reflective mirror group are arranged lined up in a direction orthogonal to the longitudinal axis direction of uniaxial solar-tracking reflective mirrors. The uniaxial solar-tracking reflective mirror group is arranged so as to be sandwiched on both sides by the first biaxial solar-tracking reflective mirror group and the second biaxial solar-tracking reflective mirror group. Each mirror group sends solar heat received during uniaxial or biaxial tracking in accordance with the position of the sun, to a heat collecting device.

Abstract: A solar panel positioning assembly having at least one fluid filled tank that is connected to at least one piston. The fluid filled tank is shaded by a solar panel when the panel is perpendicular to the sun. When the panel is not perpendicular to the sun, the fluid filled tank is heated by the sun, causing the fluid to expand and increase pressure in the piston. As the pressure increases the piston moves the solar array until the solar panel is perpendicular to the sun.

Abstract: The invention is a system and method for heliostat mirror control. Here, each heliostat mirror generates a low intensity “signal beam”, directed at an angle off from the heliostat mirror's high intensity and sensor blinding “main beam” of reflected solar energy. The low intensity signal beams may be created by reflecting a small portion of the incident solar light at an angle from the main beam, by reflected artificial light, or from lasers shinning onto mirrors from known locations. The signal beams are detected by optical sensors mounted way from the main heliostat receiver focus, and can be used in a closed loop control system to efficiently ensure that individual heliostat mirrors in a heliostat array accurately track sunlight and direct the sunlight to a central receiver. Because heliostat mirrors need not be taken “off sun” for positioning, the system allows heliostat arrays to be run at high efficiency.

Abstract: An autonomous passive solar tracker having a thermal actuator that is connected through a cable and pulley and drum to a spring. The drum and spring are mounted on a cross beam of the tracker frame. The cable is attached on one end to the actuator push rod. It then threads through the pulley and wraps around the drum. The spring biases the tracker to pivot towards one direction, and the actuator when heated and extended forces the tracker to pivot in the opposite direction. The tracker is oriented so that the spring has a bias to pivot the tracker to the east, and the outward force of the actuator rod against the cable causes the actuator to pivot to the west. One may take advantage of this tracking by attaching a solar collector to the frame of the tracker.

Abstract: An autonomous heliostat (1) having an independent autonomous control function and eliminating the need for a complicated control by a computer or the like is provided. The heliostat includes a target sensor (19) for controlling reflected light (R) from a mirror component (5) to direct it to the target sensor 19, and a search sensor (12) for catching sunlight (S) to guide reflected light from the mirror component to the target sensor, thereby to autonomously start control by the target sensor.