Why They Are Needed — How They Work
Solar energy technology development is focused on delivering more energy production in a smaller space and at a lower cost per kWh. Making existing solar panels more productive is one alternative to accomplish that goal. By following the sun more directly, solar trackers make better use of the available sunlight at any given time.
Background on Daily Solar Energy
There are a lot of variables that change the available sunlight throughout the year. Of course, every day the sun moves across the sky from dusk to dawn almost no matter where you are. And depending on your spot on the globe, the sun’s position in the sky changes with the seasons. The higher the latitude, or further north of the equator we are in the U.S., the more the seasons impact available solar energy.
When a solar panel is fixed-mounted, whether on a roof of a certain pitch (tilt), or in a ground mounted array with an engineered tilt, it only receives maximum solar energy near the middle of the day. This is when the sunshine is most directly contacting the solar panel. As you move hours before or after that, the light becomes increasingly more indirect. The amount of energy the panel can generate per hour (Wh) is reduced.
Changing the solar panel’s position over time is a relatively straightforward way to reverse that trend to varying degrees. Click on these images below for a clearer illustration.
Solar Trackers in Action
Using sensors and actuators, solar trackers almost continuously reposition an array of panels at one time.
Single-axis trackers maximize daily energy production.
This style adds an extra dimension to ground mounted solar energy systems. Where a ground mounted solar panel is fixed in all dimensions, the single-axis design frees up motion in one direction in order to maximize daily energy production. We engineer both designs so that the panels are in the best year-round position on the fixed-axis. That is, the tilt or angle of the panels is optimized relative to the north-south direction so that energy production overall is good enough from winter to summer.
Dual-axis trackers improve year round production.
This style adds two extra dimensions. In addition to improving the daily production as do single-axis systems, these designs also increase production throughout the seasons as the solar panels can be repositioned (re-tilted) to even more directly capture the sunlight from winter to summer.
Thanks to a growing number of designers and manufacturers for each style of tracker, the range of costs and performance has broadened. Such diversity translates to more options for circumstances that are not adequately met by a rooftop solar or fixed-tilt ground mounted solar energy system. However, there are no hard and fast rules for any one site or location. We invite you to contact us to address your needs more specifically and to find out if a solar tracker will work best for you.