In my experience, trackers have never made sense in off grid residential applications. In general terms, an expensive dual-axis Wattsun tracker offers a ~35% potential increase in daily solar gain around the summer solstice, and only a 10-15% gain in winter, due to seasonal sunpath variation. Any off grid residence has maximum load in winter, not summer - for most folks summer produces an excess, if sized well for winter loads. If you need more solar input, add panels rather than a tracker. With specific exceptions, I would design for winter loads, with a pole top rack for easy (and usually one-person) seasonal adjustment. I also advised clients to set the PT rack tilt angle to latitude from around the 10th of February to the 10th of November, and latitude +15 degrees for the six weeks either side of the winter solstice, December 22. This was instead of adjusting tilt angle on the equinoxes. My installations were in the desert southwest but the principles apply anywhere. Also, my experience with Solar Rackworks has been top tier for decades. Jeff Randall cut his teeth at Zomeworks in solar’s early days, was the engineer who designed Direct Power and Water’s racks, waited out his non-compete after PLP bought DP&W, then started SR with 30 years’ production experience. And he was always willing to modify a design for a specific client or project. Allan Sindelar Fully retired, finally NABCEP & Journeyman licenses expired On Mar 8, 2024, at 3:50 PM, Dave Angelini Offgrid Solar via RE-wrenches <[email protected]> wrote:
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