Solar Mounting ideas for 26x

kappykaplan · May 5, 2019

@Sumner should be able to help you out.

Brian D · May 5, 2019

Welcome to SBO!

175Ah is not realistic, at least not in my book. You are talking 2.1kWh of solar panels. That is 175Ah x 12VDC. I think for that size boat you might realize 200w panel (2x100w each) that will give you 16Ah for about 5 or 6 hr per day. I could be wrong but that is how I understand solar to work. 5 hr/day of peak energy, and that is the panel is perpendicular to the sun.

MikeHoncho · May 5, 2019

gmcgough said:
Hi Everyone,
I am a new owner of a MacGregor 26x. I need to install solar for 2 reasons.
1. No power where my boat is stored. (but plenty of sunshine)
2. I am using a refrigerator (rated at 5 amps.....usage will depend on duty cycle and temperature)

I would like to install around 120-175 amps of solar. I have experience with solar but that was installing it on my flat roof camper. The 26x is a bit more complex for mounting.

Now for the 2 big questions............
Where can I best install the solar panels? (and still use my bimini top, have reasonable access into the boat from the rear ladder and avoid shadows as much as possible)
Is there an inexpensive way to install the solar panels? (stainless steel tubing and the associated welding seems like it will cost more than the solar setup)

I can do most work myself.....but not welding. I have been scratching my head on how to do this task myself without spending a fortune on making the mounting system.

Any advice would be greatly appreciated. Even better if you have the engineering plans for the install. Otherwise pictures are very helpful.

Thanks,
Gregg

Amps? Do you mean watts? Is 26x a size? Sorry, I'm not a expert but I did just install 2 100watt panels and system on my boat davits. Kind of sounds like the hotel commercial....
I utilized the existing cross member as my primary support then added a roll bar structure to give each panel three mounting points. This was 3/4 SS tube with slip fittings. You don't need ( and probably don't want) to weld. I'm very happy with my set up. I've had it in 25+ knot winds with no movement with the panels tilted. It's set up to release the added cross bar end to tilt the panels forward or back. Solar performance wise comes next week with a week trip. But I've been getting a little under 10 amps in non direct sunlight while day sailing. My controller is a MTTP 40 amp and my fridge is a new Isotherm with the energy conservation module, 4 81amp/hr batteries and a 40 amp alt. The marine electrical manual that everyone recommends in here has a great chapter on system engineering and I wouldn't start without visiting Mainsail-s site. Hope that helps.

Sumner · May 5, 2019

Which fridge did you get? Is it a compressor type? How long will you be on the water at a time?

If the fridge is a good one I've found that if you are going to be out longer than 3 days with a fridge and other loads 200 watts is going to probably be minimum. Throw in a day or so of cloudy weather and even 200 watts is just getting by unless you are running your outboard a fair amount.

I had 175 watts on a trip to Florida for about 7 weeks and had to run a gen-set I made for about 6 hours during the trip total. After going to 200 I haven't had to run the gen-set. I now have 560 watts on the Mac since I wanted to run a trolling motor some (haven't done it) so now on 2 week trips I never worry. Same with the Endeavour have 480 watts and in the last 3 months on the water never had to once run the diesel or generator for power and we had cloudy days.

Not sure if I can help much with the mounting since I have a tig welder and use aluminum for all my projects. You are right about trying to get it aft so that it has as few shadows as possible on the array.

I'd also recommend going to two 6 volt golf cart batteries in series for better storage. They will start your outboard and if worried about not having a separate start battery pick up one of the small jump start battery packs and take it along. I have four batteries on both boats and never see the charge go below 60%. Get a good MPPT controller and maximize wire size to get all the energy you can out of the array you have.

https://www.colemanair.us/vp_asp/Scripts/Articles/TheBasicsAndBeyond5_WireSize.htm

Good luck with your install, you will love the results,

Sumner
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1300 miles to The Bahamas and Back in the Mac...
Endeavour 37 Mods...
MacGregor 26-S Mods...
Mac Trips to Utah, Idaho, Wyoming, Canada, Florida, Bahamas

Brian D · May 5, 2019

This is how I mounted my 50 watt panel. Most practical location. Plus, I can fold the panel down if I get in a tight space.

Brian D · May 6, 2019

550*680*35mm/21.6x26.7x1.4 inches