Just recently found this forum and I have a PV positioning question. I have plans for a stand alone 10KW PV system that will tie into the grid. I was looking at having pedestals with two positions for the tilt, one summer tilt 15 degrees one winter tilt 58 degrees (I'm in Wisconsin). So kind of a poor man's tracking for the seasons. My idea is that the panel framework would be hinged at the top and swing in or out from the bottom. This adjustment of the tilt could be done by one man. In running the numbers in the PVWatts calculator and I get a total gain in energy of about 800KWH per annum over the best fixed tilt. So my question is, is it worth it cost-wise and risk-wise(stability, maintenance)to have this framework made? Thanks, Dale

So say $100/year. What is the additional cost to build an adjustable rack and what is your time worth?

I don't have any idea how much the cost differential is I am the client not the builder. I was wondering if there were any significant drawbacks to the idea and if it had been done before.

Yes, it has been done before. Drawbacks are engineering time and materials to produce the adjustable supports and labor time necessary to do the seasonal adjustments. You already know what the benefits are.

So what is the cost differential? Does it add 10% to the cost? 20%? Are there any additional risks to the frame for having this built in?

Just google Build it Solar. There are hundreds of DIY PV mount designs including this one showing all the design/fabrication issues along with the pros/cons of each design.

Thanks I will go to the Google.

My owner installed system has 2 arrays with adjustable tilt mountings, and the adjustment feature cost me about $20 per array. Not sure what it would cost if you had a contractor do it or used the fancier and more expensive mounting systems. Mine uses Unistrut and stainless steel bolts and wingnuts for the adjustment feature. I have friends whose ground mount is adjustable using a cordless drill driving a nut-type fixture on the rack, and their racking cost was very reasonable, although I no longer have the cost figures on their project. Theirs is a ballasted ground mount used in part because of bedrock very close to the surface.

Reading at the Build It Solar site seems to suggest a 400 to 600w gain was the break even point. They didn't specify what size array this was based on. My gain would be 880w so looks good that way. WisJim how many arrays were you using? I'm going to set up my system near Portage, WI so you might have some tips for me.

I think worth for your money

I am thinking about a cantilever design where the weight of the upper panel counterbalances to make the adjustment easier. This is to be my retirement home so my old bones need easy ways to adjust the panels. I like the idea of using the cordless drill.