Aimable Solar Panel Mount for an arch?

[Pete7]

Billknny says he has a pair of 315 amp solar panels. How much do they weigh? say 24 kgs each. That is quite a lot for a plastic molding and even the magma ones could do with a bit of extra support perhaps?

Pete

[thinwater]

Maybe I'm just thick.

A boat swings at anchor. Which direction do you point it? I think you will find (do the trig) if the yawing is as little as 30 degrees over a time period, you may be better off with a flat panel. If the wind shifts 90 degrees you are much worse off. 180 degrees and you just turned the solar off completely.

Are you just going to aim it south, or have it track with the hours?

If you are in a marina, sitting still, you can plug in.

Averaged over time, including the hours or days were you don't activity tend the aim, is there any actual up-side here? Also subtract for windage and weight. This makes sense on land, most of the time, but I think not on a boat.

[newhaul]

Originally Posted by thinwater

Maybe I'm just thick.

A boat swings at anchor. Which direction do you point it? I think you will find (do the trig) if the yawing is as little as 30 degrees over a time period, you may be better off with a flat panel. If the wind shifts 90 degrees you are much worse off. 180 degrees and you just turned the solar off completely.

Are you just going to aim it south, or have it track with the hours?

If you are in a marina, sitting still, you can plug in.

Averaged over time, including the hours or days were you don't activity tend the aim, is there any actual up-side here? Also subtract for windage and weight. This makes sense on land, most of the time, but I think not on a boat.

at anchor your boat will point into the wind . Panels mounted flat will produce power when ever the sun is above the horizon . Look at how the sun tracks in the tropics it is basically directly overhead at noon. So it doesn't matter what way your boat is pointing. ( I use the tropics as an example only ) . One last thing if solar didn't work good on boats why is there so much mounted on boats?

[zboss]

Originally Posted by Pete7

Billknny says he has a pair of 315 amp solar panels. How much do they weigh? say 24 kgs each. That is quite a lot for a plastic molding and even the magma ones could do with a bit of extra support perhaps?



Pete

The magma ones are really strong, I think they are aluminum?

We ended up using the sea dogs for our 140 watt panel and they seem just fine but 300 plus watt panels have a wide empty space between panel edges and weigh a lot. I would be concerned that the bouncing would flex aluminum cross braces a bit too much. So.... he is left with using stainless steel in a design a bit more robust.

As far as swinging at anchor, the trade winds in the Caribbean blow pretty consistent from the same direction, east to west... the sun rises east and west west, so your stern spends a lot of time looking toward the sunset. So panels that tilt can get you that extra power.

Also, water reflects a lot of usable light. I know when we had our panels out like wings and they were down on the sides, they produced a lot of power starting just after sunup. I would have to raise them up until 10 or so.

[newhaul]

Originally Posted by zboss

The magma ones are really strong, I think they are aluminum?

We ended up using the sea dogs for our 140 watt panel and they seem just fine but 300 plus watt panels have a wide empty space between panel edges and weigh a lot. I would be concerned that the bouncing would flex aluminum cross braces a bit too much. So.... he is left with using stainless steel in a design a bit more robust.

the possibility of flexion of the cross brace that the rail mounts are attached to is the reason I prefer to use aluminum channel and not the flat bar that most commercially available mounting systems seem to use. The actual cost difference can be measured in pennies. ( actually cost extra 2 bucks per panel) .