Solar array footprint concerns on 45ft mono

[Tightrrs]

First post - I’ve read a lot of the great advice on this forum, but I’m still unsure what to do

We’re starting to get our boat ready for offshore adventures to sunnier climes, aiming to maximise time on the hook. The widely offered advice is to maximise solar capacity, and I prefer the idea of rigid panels on a s/s arch. The arch would provide dinghy davits as well.

I was thinking of 3 LG residential panels, around 1000 watts in total. However, that’s over 5 sq metres of panels! I’m concerned about the aerofoil aspect and potential windage issues.

Am I right to be concerned?

[tkeithlu]

Welcome to the forum, Tightrrs.

[Montanan]

Compare your 5 square meters , 53 square feet to a bimini covering a cockpit, be that hard or soft and it is roughly a comparable degree of flat surface addition.

Does it add to windage, yes. Some leeward input. Drag especially when headed up wind, added push when headed downwind and more force when moored or anchored, but not as much as the vertical surface of a dodger or pilot house or raised salon.

And nowhere near as much as a dinghy hanging on a davit and the davit structure.

Enjoy the solar power.

[Tightrrs]

Thanks for the advice.

I’m also adding a radar. Putting it on the arch would be a neat solution - would shading be a significant issue? Has anyone got any experience?

[Montanan]

Partial shading can significantly reduce power output. Much depends on the specific circuit design and inverters that you chose.

Somewhat complex subject. Recommend reading online literature.

A useful reference: https://couleenergy.com/solar-panels...ts-of-shading/

Best to positioning shading objects away from the panels, or place them under the panels. The panels could shade your radar by simply mounting your panels over the radar, instead of placing the radar over the panels.
Of course one can't move the mast out of the way, but one can shift the boom to avoid it shading a panel when at anchor. And one can shift how your vessel sits at anchor, by adjust a line from your rode to the aft of your vessel and swing the hull to minimize shading.

[thinwater]

Perhaps there are some deck areas that don't see foot traffic. Even a little will help with the math.

[RickG]

We run two Panasonic 330 watt residential panels over our bimini. No problems, but we do take them down for named storms.

Cheers, RickG