Photovoltaic (PV) solar panels are almost the perfect power generating technology: they're clean, they're quiet, they have zero moving parts, and they're increasingly cheap. But they have a big problem: they work best when they face the sun -- and the sun moves. It's straightforward enough to rig up computerized tracking systems to move them, but that siphons off some of the power the solar cells produce, and adds a lot of potential points of failure with moving parts for each panel, and expense in building racks strong enough to hold both panels and tracking mechanisms.
Do we chose simplicity and lower output with our PV setups, or add complexity to squeeze some more percentage points of efficiency out of the sun? A Menlo Park firm has a possible compromise solution, and it relies on robots.
It's expensive enough to have your panels swing from east to west to follow the sun each day. If you really want to maximize your PV cell's output, they should also be able to swing up and down as the sun moves away from and toward the horizon. Allowing your PV cells to track the sun on two axes can boost output by as much as 45%. But dual-axis drive systems for each panel can really make your installation costs mount up.
Silicon Valley startup QBotix announced yesterday that the company has developed a way to adjust a field of solar panels to point at the sun without adding a drive mechanism for each panel. The firm's "QBotix Tracking System" consolidates all those drive mechanisms -- and thus all those potential points of "moving parts" failure -- into one small robot -- "Solbot" -- which moves through an array of dual-axis PV panels on a simple monorail, adjusting each panel in turn, as shown in the video below (courtesy Forbes reporter Todd Woody.)
Each robot can move quickly enough to keep an array of 200 panels aimed at the sun.
According to QBotix, their robot helper offers the promise of increasing PV output by as much as 15% over single-axis tracking systems (and 40% over fixed-plate systems), while saving 15% in installation costs. There's very likely a potential maintenance cost savings, as well: rather than having a mechanic on hand to repair 200 dual axis drives and losing valuable power output until a fix is made, a mechanic could just swap in a spare robot and fix the ailing one.
As QBotix's CEO Wasiq Bokhari points out in the video, the 1/200 robot/panel ratio means that the firm's system could easily be used in distributed generation applications of 300 kilowatts or so. The monorail system can run up slopes between dispersed panels, allowing installation in a variety of different topographical settings without necessarily paving everything underneath: a boon for incorporating solar into existing urban settings.