Panel mount at 30 ft… In the wind…

[LithiumCanuck]

I have to add more panels on my system but can’t place them on my roof because of my neighbor‘s trees…

I found a 30 ft pole that could place my panels high enough to eliminate the shade problem. It’s an aluminium pole, 8in at the base, 6 at the top ( the ones cities use for street lights).

I want to use 2 of the new Canadian-solar panels but I’m worried about the wind. Could strong winds push hard enough on my 2 4x8 panels to break the pole?

Any advice is welcome.

 

[12VoltInstalls]

Could strong winds push hard enough on my 2 4x8 panels to break the pole?

Strong, gusty winds can do a lot of things. However, I’d be inclined to say 50 or 60 square feet would be ok. But I don’t know your wind. I’d probably try it.
Three guy wires would probably guarantee it under most circumstances. I’d be concerned about the base! I’ve been involved in pouring footers for parking lot lights- there’s a lot below the ground if done to specs. You’d need as firm a base.

 

[LithiumCanuck]

Strong, gusty winds can do a lot of things. However, I’d be inclined to say 50 or 60 square feet would be ok. But I don’t know your wind. I’d probably try it.
Three guy wires would probably guarantee it under most circumstances. I’d be concerned about the base! I’ve been involved in pouring footers for parking lot lights- there’s a lot below the ground if done to specs. You’d need as firm a base.

I have a 9 ft x 24‘’ concrete block with studs. 8 ft under the ground should do…. Hopefully…

 

[MichaelK]

Another alternative is get even more panels, then wire them all in series. I'm running DC current ~130' at 120VDC without any noticeable voltage drop from a very sunny spot over to my combiner box.

This strategy could allow you to pick a sunny spot away from trees and your neighbor for a sturdy ground mount.

BTW, is the cabin in your signature pic the location for the solar? Why would your roof not be a good location to place panels?

 

[LithiumCanuck]

If you look at the rear top corner, I already have 4 x 275W panels. Problem is the roof is behind trees most of the time during winter. 75’ behind, I have a nice sunny spot, but……. 30’ above ground……

 

[WYtreasure]

I would put a recording wind speed anemometer up at 30 feet for quite some time before committing to panels at that height.

 

[Zwy]

I have to add more panels on my system but can’t place them on my roof because of my neighbor‘s trees…

I found a 30 ft pole that could place my panels high enough to eliminate the shade problem. It’s an aluminium pole, 8in at the base, 6 at the top ( the ones cities use for street lights).

I want to use 2 of the new Canadian-solar panels but I’m worried about the wind. Could strong winds push hard enough on my 2 4x8 panels to break the pole?

Any advice is welcome.

There is leverage at the bottom of the pole and takes ballast to counteract.

I have an MT Solar Top of the Pole 16 panel double pole mount. Array is 15 feet tall and 3 feet off the ground at 60 degree tilt. 16 panels total. It is 30 feet long mounted on 2 6inch SCH80 poles with 3 feet of concrete around each pole, concrete is 7.5 feet deep.

The force at ground level at the 103 mph rating for this area is 77,332 lbs, wind load on array is calculated at 8,828 lbs. That 10.5 feet of pole has that much leverage at the bottom of the pole.

30 feet up, well, that is some serious leverage. Will take some good ballast in the ground.

 

[WYtreasure]

There is leverage at the bottom of the pole and takes ballast to counteract.

The force at ground level at the 103 mph rating for this area is 77,332 lbs, wind load on array is calculated at 8,828 lbs. That 10.5 feet of pole has that much leverage at the bottom of the pole.

Those are some serious numbers. Damn!
Guy wires might help but if the wind comes from the wrong direction the panels might just leave.

 

[12VoltInstalls]

Guy wires might help but if the wind comes from the wrong direction the panels might just leave

Guy wires in three directions significantly reduce effective loading

 

[Checkthisout]

You want that beautiful cabin to have a big ugly pole next to it with solar panels on top?

 

[Hedges]

Ballast and foundation would keep base from tilting, but pole could buckle and collapse. Aluminum is not known for the strength of steel.
I would favor guy wires as mentioned, or 3 poles as a tripod. I believe in triangles, trusses that take tension/compression but not torsion.

Feel free to calculate wind loading and bending moments. There are equations and calculators on-line. then compare stresses at base to yield strength of the material and diameter.

It sure looks like you could add more panels, should get light some hours. if unshaded area is limited, what efficiency (watts/m^2) are existing panels? You can get 200 W/m^2 or a bit more; if significantly higher than what's there, consider replacing. I would consider having them project above ridge of roof.