Solar options

JUSTINHALEWOOD

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Hi All,
I've been working up some options for a solar installation on our HR36 and would be interested in the forum's opinions. Some notes to go with the PDF attached:
- I have tried to come up with a system to mount 170 watt panels either side (see slide 5). To reduce weight, I have semi-flexible panels mounted on 3mm Dibond board - this plus the panel weighs c.6.6kg vs. 8kg for the 115 watt rigid panel.
- I plan to use the NOA brackets to grip the panels onto 25mm S/S tube running between the pushpit and the first stanchion. I've included two options to connect the S/S tube In particular, between the S/S tube fittings and NOA brackets, I'd be interested in people's thoughts as to whether there will be enough 'tension' (anti-twist?) to hold the panels in a horizontal/off-set position. I don't really want to use props, although appreciate these can work well.
- I've also started to draw an array for our Bimini (not yet installed). Interested in people's thoughts on Bimini vs. guardrail, particularly with regards to the lifespan of the panels.
Any and all other thoughts/advice would be gratefully received.
Thank you in advance!
Justin
 

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I'd steer if at all possible clear of any semi and flex panels as they are much more expensive and last v.little compared to the rigid ones.

I'd most likely go option 1 and rigid panels. I'd probably up the size a bit. Unless you can fit rigids on top of the bimini (mate on a mobo has done that successfully but it's too high up to see the panels, not the same as on a sailing yacht)
just to add that a couple of friends with sailing boats and flex panels on biminis have lost or ripped bimini cloth on a couple of occasions (in two seasons...) Looking at the setup seemed fine to me although it's unlikely to manage to secure flex panels on a bimini underlying frame everytime (holes/frame mismatch)

V.
 
I'd steer if at all possible clear of any semi and flex panels as they are much more expensive and last v.little compared to the rigid ones.

I'd most likely go option 1 and rigid panels. I'd probably up the size a bit. Unless you can fit rigids on top of the bimini (mate on a mobo has done that successfully but it's too high up to see the panels, not the same as on a sailing yacht)
just to add that a couple of friends with sailing boats and flex panels on biminis have lost or ripped bimini cloth on a couple of occasions (in two seasons...) Looking at the setup seemed fine to me although it's unlikely to manage to secure flex panels on a bimini underlying frame everytime (holes/frame mismatch)

V.
Thanks Vas!
 
I think it depends how you use the boat.
Personally I would look at a semi-flex on the deck first but that may only give 100W.
The problem with both your other proposals is that they will probably need removing to do anything other than fair weather sailing so you won't benefit when you need to recharge batteries after an overnight passage.
I certainly know of boats that mount semi-flex on biminis but I certainly wouldn't set off on a passage with this unfurled.
Semi flex panels are really not very robust unless mounted on a totally rigid backing.
Are you needs at anchor or on passage? If on passage maybe a Watt & Sea is an option?
 
Semi flex on dibond appears to be a marginal weight saving, and you will pay as lot more for the panels, which are unlikely to last as long as rigid ones.
Perhaps you could use a lighter backing material- maybe Foamex? Or just buy rigid panels and save a ton of money.

You don't need to spend a lot on solar. I'm installing 2x 320w panels, 16.8kg each, total cost £266 of which about a third is just the delivery.
 
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We’ve got (I think) 2 x rigid 150w mounted the same way on SS tube between the pushpit and first stanchion. The panels are old so unsure of the exact spec...

But the whole lot is held together with U-bolts (and is all rather janky!) but works fine. The fixings ‘grip’ enough to hold the panel in any position, which very occasional tightening, so I should think with the NOA fittings it’ll be fine.

I’d also vote for this as a simple, neat and affordable option. I might even look to upgrade ours (from being all just u-bolted together) based on your design! ??
 
Does that include your regulators? I can't find 2 x 30A MPPT regulators for that cost, let alone panels.

No that's just the panels.
If you wanted to keep the budget right down you could but more panels and go PWM... assuming you have the space... but it's definitely a compromise.
 
Does that include your regulators? I can't find 2 x 30A MPPT regulators for that cost, let alone panels.

No that's just the panels.
If you wanted to keep the budget right down you could but more panels and go PWM... assuming you have the space... but it's definitely a compromise.
 
Depends what you are trying to achieve.

I have velcro sewn into my bimini and can put 4 x 150w panels up there. So far, I have found that just 2 x 100w panels through a PWM controller provides plenty enough power for me needs, but I have the ability to add a further 2 panels through a second MPPT controller if I need to.

There are semi-flexible panels, and semi-flexible panels. I went through a few of the cheap ones to start with (they only last a couple of years and then start to delaminate), but now have ETFE ones, which are a lot tougher and are lasting well.

The benefit with having them on the bimini for me is that they are out of sight, out of harm's way, and in clear sunlight.

I paid £500 for 4 x 100w ETFE panels.
 
I have installed semi-flexible and rigid solar panels on previous boats. The semi-flexible panels are convenient as they can be fixed on a curved area of a deck, but they are not durable at all and the output dropped down to less than 50% within 4 years. The rigid panels are cheaper and much better in terms of efficiency and durability.
 
Thanks Bob - do you have details of the Velcro arrangement you could share please? Thank you!

Depends what you are trying to achieve.

I have velcro sewn into my bimini and can put 4 x 150w panels up there. So far, I have found that just 2 x 100w panels through a PWM controller provides plenty enough power for me needs, but I have the ability to add a further 2 panels through a second MPPT controller if I need to.

There are semi-flexible panels, and semi-flexible panels. I went through a few of the cheap ones to start with (they only last a couple of years and then start to delaminate), but now have ETFE ones, which are a lot tougher and are lasting well.

The benefit with having them on the bimini for me is that they are out of sight, out of harm's way, and in clear sunlight.

I paid £500 for 4 x 100w ETFE panels.
We’ve got (I think) 2 x rigid 150w mounted the same way on SS tube between the pushpit and first stanchion. The panels are old so unsure of the exact spec...

But the whole lot is held together with U-bolts (and is all rather janky!) but works fine. The fixings ‘grip’ enough to hold the panel in any position, which very occasional tightening, so I should think with the NOA fittings it’ll be fine.

I’d also vote for this as a simple, neat and affordable option. I might even look to upgrade ours (from being all just u-bolted together) based on your design! ??
Depends what you are trying to achieve.

I have velcro sewn into my bimini and can put 4 x 150w panels up there. So far, I have found that just 2 x 100w panels through a PWM controller provides plenty enough power for me needs, but I have the ability to add a further 2 panels through a second MPPT controller if I need to.

There are semi-flexible panels, and semi-flexible panels. I went through a few of the cheap ones to start with (they only last a couple of years and then start to delaminate), but now have ETFE ones, which are a lot tougher and are lasting well.

The benefit with having them on the bimini for me is that they are out of sight, out of harm's way, and in clear sunlight.

I paid £500 for 4 x 100w ETFE panels.
 
Great suggestion, thank you
We’ve got (I think) 2 x rigid 150w mounted the same way on SS tube between the pushpit and first stanchion. The panels are old so unsure of the exact spec...

But the whole lot is held together with U-bolts (and is all rather janky!) but works fine. The fixings ‘grip’ enough to hold the panel in any position, which very occasional tightening, so I should think with the NOA fittings it’ll be fine.

I’d also vote for this as a simple, neat and affordable option. I might even look to upgrade ours (from being all just u-bolted together) based on your design! ??
I think it depends how you use the boat.
Personally I would look at a semi-flex on the deck first but that may only give 100W.
The problem with both your other proposals is that they will probably need removing to do anything other than fair weather sailing so you won't benefit when you need to recharge batteries after an overnight passage.
I certainly know of boats that mount semi-flex on biminis but I certainly wouldn't set off on a passage with this unfurled.
Semi flex panels are really not very robust unless mounted on a totally rigid backing.
Are you needs at anchor or on passage? If on passage maybe a Watt & Sea is an option?
 
Thanks Bob - do you have details of the Velcro arrangement you could share please? Thank you!
I have 2 long strip across the back part of the bimini and 2 long strips across across the front part. Distance between the outside edges of the strips is 500mm (just under the width of a panel).
 
The NOA mounts are unlikely to hold your panels horizontally at full extension.

I have two 80W rigid panels mounted on my pushpit rails using NOA mounts. To hold them out I have to either use props or adjust the position so that about a third of the panel is in towards the cockpit to balance the panel somewhat.

My panels hold for a while in a horizontal position at full extension using just the grip from the adjustment device. But it has to be so tight that I fear stripping the threads and they always slip back into the vertical position even at the dockside. They won't resist the forces created by waves.
 
I have 2 long strip across the back part of the bimini and 2 long strips across across the front part. Distance between the outside edges of the strips is 500mm (just under the width of a panel).
Thanks Bob - stitched onto the Bimini and double sided tape onto the solar panels?
 
Btw. Have a careful look at the geometry of your panels on the rails. I mocked mine up in wood and cardboard to check they cleared winch handles. Fine when towards the horizontal position but I normally sail with them stowed vertically and they then restrict one set of winches. They also clash with the proper 'furthest aft' lead for the sheets on my lightweight 'ghoster' genoa - cruising chute or spinnaker on a more modern boat. And it sometimes gets exciting when mooring - they can get in the way of lines being thrown or secured and on a couple of occasions I forgot to stow them until the last moment backing into or moving out of a space only centimeters wider than my boat.

All of these might need factoring into how to mount your panels on your boat.
 
Btw. Have a careful look at the geometry of your panels on the rails. I mocked mine up in wood and cardboard to check they cleared winch handles. Fine when towards the horizontal position but I normally sail with them stowed vertically and they then restrict one set of winches. They also clash with the proper 'furthest aft' lead for the sheets on my lightweight 'ghoster' genoa - cruising chute or spinnaker on a more modern boat. And it sometimes gets exciting when mooring - they can get in the way of lines being thrown or secured and on a couple of occasions I forgot to stow them until the last moment backing into or moving out of a space only centimeters wider than my boat.

All of these might need factoring into how to mount your panels on your boat.
Thank you - salient advice.
 
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