Dual-Axis Trackers
M1 Dual-Axis Tracker
M2 Dual-Axis Tracker
M8 Dual-Axis Tracker
SolarSpace Dual-Axis Trackers are using an array of mirrors and receivers, in landscape format. The sizes were chosen to minimize system cost based on a number of factors. The elongated landscape format minimizes self-shadowing, while the relatively small size minimizes wind load, mass and fabrication cost per unit area. It also simplifies installation and maintenance. The small size also allows low mass of steel per unit area supported.
The mirrors are axisymmetric paraboloids of 1.5 m focal length generating 1,000x concentration and the sun is tracked with 0.01° accuracy. Mirrors are square, 1.65 m on a side with area 2.7 m2, and are made from a single piece, low-iron, 4 mm thick B270 glass. The back surface is coated with silver and then over-coated with copper and paint for protection. The mirrors are supported by four aluminum pads attached by silicone adhesive. The mirrors are mounted on a conventional fishbone elevation structure with cross ribs and attachment points. The “tee” structure attached to the fishbone spine support the receivers above the mirrors. Tracking motion in elevation is driven by a linear screw actuator and in azimuth by a slewing bearing. The applied gravity and wind loads are transmitted to well-spaced ground supports. Wind forces and torques on the supported mirrors are transmitted to the ground supports as predominantly lateral or vertical forces, rather than torques. The supporting pedestal is a steel angle iron, secured to the ground by three screw anchors. These are lightweight, take only a few minutes to install with lightweight equipment, and are immediately ready for use. No concrete is used in the foundation.