Shadow question

Frxddy

What will the shadow of a 1/2" cable do to the production of a solar panel?

I have a 60 foot tower that I am considering using as a foundation of a grid tied system. It is supported by four one half inch steel cables. At any one time a single shadow could fall across any panel.

I have this idea of junking my 5.5k wind turbine (poor location...long story, aren't they all?) and using the tower to hold perhaps 4K of panels. It is a home built tilt up tower. Wind load would be no problem, this tower is way strong. With minor changes I could have it tilt at different times of the year. With more changes I could have it swivel to follow the sun during the day. But, if a line shadow "kills" a panel, this will not work at all. If this just won't work I have a nice south facing roof on my house.......

Gazz

Re: Shadow question

My experience with shadows is that they can do very funny things and exactly how it would effect your set-up is hard to say. SMA do a new invertor that is designed to manage shawdows better, also can you split it into a numer of strings so the effect would not impact on the whole set-up. My proble was not the shadow but the change in shadow it was as if the inverter culd not adjust itself for the moving shadow from panel to panel.

niel

Re: Shadow question

would it be possible to relocate the guy wires in question? 1/2 inch guys are very heavy excepting for very tall commercial towers so i'd be curious of that and its height. is the tower multi-legged and how many?

stephendv

Re: Shadow question

See this discussion where a TV aerial knocked 40% off the production of a PV array: http://www.navitron.org.uk/forum/index.php/topic,13417.msg150311.html#msg150311

Frxddy

Re: Shadow question

Thanks for the input.

Here is a pic of the tower. It is 62 feet tall, and the turbine weighs just over 1,000 pounds. It tilts down for maintenance. No cables can be moved or removed & still maintain strength. The tower itself is about 1,500 pounds. Just like a bridge, if one cable breaks, the entire rig is in jeopardy, only more so here.
If I built brackets for solar panels some would be above all the cables, but most of the panels would go outside the "inner cables", but inside the "outter cables". That would make a 1/2" wide shadow on some of the panels some of the time. As the panels went down the tower, the cable would be further away.

I'm thinking I should buy one panel & do some testing.

<edit> Wow... I just followed some links & read of a couple different cases....it looks like even a small shadow makes a huge difference! Hmmm..... Looks like the tower idea may be out.

mike95490

Re: Shadow question

I could see the effect of power line shadows on my array, so if it happens at prime solar time, over more than 1 panel, you will have problems

Peter_V

Re: Shadow question

It looks like you have lots of space, my advice would be to just ground mount the panels somewhere they won't get shadowed.

Ground mounts are generally cheaper than side of pole mounts anyway and you won't have to worry about the cable shadows.

cpetku

Re: Shadow question

Gazz wrote: »

do a new invertor that is designed to manage shawdows better, .

With 4K DC and shadows this sounds like a good application for Enphase units as it will fit on a single string AC branch.

Frxddy

Re: Shadow question

Thanks for the replies. I guess I'm leaning toward either roof mount all the panels, or most on the roof and maybe play with a small number on the tower.