solar

[JemShaun]

Hello again everyone, back up and running after my illness, I am looing at a boat which has no solar, but as it has a washing machine, and we will be CCers (not Cmers) and full time live aboards we are looking at what we need. My opinion is go as max as possible on a 57ft boat, with the assumption that once the batteries are full the rest of the solar could heat the water. What set ups do you guys have, and what would be your recommendations please. Need as much help on this as possible. My budget will be £3k

 

[blackrose]

There are quite a few threads in the archives which are worth reading. To start you basically need to work out the maximum area of roof space available for panels (without restricting your movements on the roof if that's what you do) and then start looking around for panels of the right sort of size. I was told from the outset to look for panels with over 40v open circuit voltage (Voc).

 

Then if you have more than one panel you need to decide whether you're going to connect panels in series or parallel. Series mean you multiply voltage by the number of panels (amps stay the same) and parallel means you multiply the amps by number of panels (volts stay the same).

 

Then you need to match your panel output with a suitable MPPT controller. If your panel output exceeds the controller's amp rating the controller will simply clip the amps going to the batteries. If your panel voltage output exceeds the controller's voltage rating you will fry the controller!

Edited March 9, 2023 by blackrose

[Alan de Enfield]

1 hour ago, JemShaun said:

Hello again everyone, back up and running after my illness, I am looing at a boat which has no solar, but as it has a washing machine, and we will be CCers (not Cmers) and full time live aboards we are looking at what we need. My opinion is go as max as possible on a 57ft boat, with the assumption that once the batteries are full the rest of the solar could heat the water. What set ups do you guys have, and what would be your recommendations please. Need as much help on this as possible. My budget will be £3k

 

 

You also need to budget for "something" (generator ?) that you will need for the 4 or 5 or 6 months of the year when you do not get sufficient solar.

You can pick up a decent Honda 2kw genny for around £1000 (£1300-£1400 new, maybe £800+ 2nd hand) so bear that in mind when costing your solar system.

[PD1964]

 I would say your decision will be either a full roof of good solar panels and less batteries or less panels and more/better batteries. As said above you’ll not be able to survive solely on solar all year. Maybe try a Marina or a mooring with elect hook-up for winter. You could spend your budget just on batteries.

 Your best to really work out how much power you’ll actually need, you may not need as much as you think? I only use my washing machine when I’m  moving/running the engine.

 This guy does a lot on boats and gives good advice on boat systems and requirements.

https://fourcountiesmarineservices.com/home/

 

Edited March 9, 2023 by PD1964

[blackrose]

20 minutes ago, Alan de Enfield said:

 

You also need to budget for "something" (generator ?) that you will need for the 4 or 5 or 6 months of the year when you do not get sufficient solar.

 

 

Not necessarily, it depends on your solar setup and power demands. I realise I have over 4m2 of panels but I'm completely off grid even in winter and can even run my washing machine from the panels when there's enough sunlight.

[JemShaun]

Very interesting.......thank you

13 minutes ago, PD1964 said:

 I would say your decision will be either a full roof of good solar panels and less batteries or less panels and more/better batteries. As said above you’ll not be able to survive solely on solar all year. Maybe try a Marina or a mooring with elect hook-up for winter. You could spend your budget just on batteries.

 Your best to really work out how much power you’ll actually need, you may not need as much as you think? I only use my washing machine when I’m  moving/running the engine.

 This guy does a lot on boats and gives good advice on boat systems and requirements.

https://fourcountiesmarineservices.com/home/

 

Thats awesome thank you, I shall have a closer look 

[Alan de Enfield]

5 minutes ago, blackrose said:

 

Not necessarily, it depends on your solar setup and power demands. I realise I have over 4m2 of panels but I'm completely off grid even in winter and can even run my washing machine from the panels when there's enough sunlight.

 

But he will have some 50% less than you have.

 

He will only have a maximim 45 feet (57' less bow and stern) x 6 feet

[magnetman]

3 minutes ago, Alan de Enfield said:

 

But he will have some 50% less than you have.

 

He will only have a maximim 45 feet (57' less bow and stern) x 6 feet

 

You can fit a heck of a lot of solar on top of a narrow boat.

 

Canadian Solar 375w Mono Perc for example.

 

Part No: CS3L-375MS-MC4-F30

Monocrystalline Panels

• Rating: 375W
• Efficiency: 20%
• Width: 1,048mm
• Height: 1,765mm

 

You could easily get 3kw on the top of the cabin.

 

 

I don't know how much @blackrose has but I doubt it is much more than 3kw.

ETA I see Mike quoted 4 square metres so at around 20 percent efficiency that would be something like 800w of solar. Not a particularly large array.

 

A narrow boat cabin top of 40ft is 12 metres long x 1.8 wide so if you did actually cover it with appropriately sized panels you would be able to achieve a total install, based on 20%, of something like 4.3kw of solar.

 

Slight overkill but there is room for it.

 

 

[George and Dragon]

We have 4.4kWp installed on the roof at home. I very much doubt we could fit that on the deckhead of our 60' NB. Well, maybe if you have nothing else there at all: the panels are 1.134m wide so without allowing for any fixing brackets that's 13.6m.

Most of us need to be able to walk on top of the boat at some time.

[AG2]

I went with a company called onboard solar for a supply and fit option.

 

Their website had lots of information information re planning for solar. 

[magnetman]

13 hours ago, George and Dragon said:

We have 4.4kWp installed on the roof at home. I very much doubt we could fit that on the deckhead of our 60' NB. Well, maybe if you have nothing else there at all: the panels are 1.134m wide so without allowing for any fixing brackets that's 13.6m.

Most of us need to be able to walk on top of the boat at some time.

 

 

This is a good point. It does depend how often you walk on the cabin top. Some people probably never do this I suppose it would depend on your general level of mobility.

 

My large solar panels (325,365 and 415w) are happy to be walked on as it happens. They don't break*. I'm not very heavy at about 75kg. They are remarkably durable. You don't want to jump on them and of course they are a little slippery.

 

I wouldn't advocate more than about 1kw of solar on a narrow boat but I know some people use a lot of power so it depends what the priorities are. Roof walking or production of electricity.

 

 

 

*Disclaimer: If you walk on your rigid solar panels and fall through and your leg becomes trapped causing you to slowly exsanguinate do not come running to me to complain.

 

 

[Alan de Enfield]

4 minutes ago, magnetman said:

*Disclaimer: If you walk on your rigid solar panels and fall through and your leg becomes trapped causing you to slowly exsanguinate do not come running to me to complain.

 

 

How about 'hopping' - can we complain then ?

[magnetman]

No allowed.

[IanD]

19 hours ago, magnetman said:

 

You can fit a heck of a lot of solar on top of a narrow boat.

 

Canadian Solar 375w Mono Perc for example.

 

Part No: CS3L-375MS-MC4-F30

Monocrystalline Panels

• Rating: 375W
• Efficiency: 20%
• Width: 1,048mm
• Height: 1,765mm

 

You could easily get 3kw on the top of the cabin.

 

 

I don't know how much @blackrose has but I doubt it is much more than 3kw.

ETA I see Mike quoted 4 square metres so at around 20 percent efficiency that would be something like 800w of solar. Not a particularly large array.

 

A narrow boat cabin top of 40ft is 12 metres long x 1.8 wide so if you did actually cover it with appropriately sized panels you would be able to achieve a total install, based on 20%, of something like 4.3kw of solar.

 

Slight overkill but there is room for it.

 

 

 

It's not 1.8m wide, allowing for gunwales and tumblehome a typical narrowboat roof is maybe 5'6" wide edge-to-edge which is 167cm, and this assumes you are OK with panels extending right to the edge over the handrails which most aren't -- so normally about 1.5m panel width is the limit, and it may well be less than this. With 1.5m you can just fit in 295W panels crossways, each of which takes 1m of roof and costs £162 from Bimble:

 

https://www.bimblesolar.com/295w-perlite-54cell-small

 

It does mean you can't walk along the roof any more, if you want to do this smaller panels are needed.

 

Almost all boats have stuff sticking up through or mounted on the roof like chimneys, mushroom/flying saucer vents, centreline loop, aerials, hatches, and there needs to be gaps between the panels to fit these in. It's also a good idea to have spaces for crossing the roof in at least a couple of places, advisable at the front of the roof and the middle (where the centreline is) -- and you can't take them all the way to the stern because of the hatch.

 

Take all this into account and in reality it's difficult to get much more than 2.5kW of solar onto a typical narrowboatboat, maybe about 2/3 of the total roof length. My 60' boat has a 43' long roof (and no vents!) and the most I could fit in was less than 30' length of panels, allowing for cross-walkways, hatch etc, which came to 2.1kW -- these are semi-flexible panels bonded down to the roof, walkable on with care (not in stilettos!) but I wouldn't want to jump onto the roof from a lockside onto them, hence the walkways. Note that I don't have any mushroom roof vents so can have long runs of panels, most boats would either have to fit them in between the vents (Murphy's law says the gaps will be the wrong size...) or raise them up high enough to be above the vents.

 

Edited March 10, 2023 by IanD

[magnetman]

You could fit wider rigid panels and elevate them by a few inches to allow hand access to the cants if needed and give room for cabin top ventilators under. I would not have a centrally fitted centre line it would be on a bridge in the cant handrail or even better have circular tube handrails.

 

I know it would alter the profile of the boat slightly to have solar sticking out and more attention needed at bridgeholes and tunnels but depending on how regularly the boat is moved and where it is used it would be doable. Not particularly sensible but as I mentioned this sort of thing will be about priorities.

 

I hope those flexible panels last alright. Not keen on them myself but they do look better than the rigid ones on a narrow boat.

 

 

 

 

[IanD]

14 minutes ago, magnetman said:

You could fit wider rigid panels and elevate them by a few inches to allow hand access to the cants if needed and give room for cabin top ventilators under. I would not have a centrally fitted centre line it would be on a bridge in the cant handrail or even better have circular tube handrails.

 

I know it would alter the profile of the boat slightly to have solar sticking out and more attention needed at bridgeholes and tunnels but depending on how regularly the boat is moved and where it is used it would be doable. Not particularly sensible but as I mentioned this sort of thing will be about priorities.

 

I hope those flexible panels last alright. Not keen on them myself but they do look better than the rigid ones on a narrow boat.

 

 

I still think your proposed install is impractical in reality -- except for boats that never move anywhere... 😉

 

The panels on my boat are so-called "semi-flexible" ones which are basically thinned PERC mono panels bonded down to an only-slightly-flexible aluminium panel, which in turn is vacuum-bonded down to the steel roof of the boat -- the whole assembly is as rigid as the roof and you can walk on them quite happily, and the top side is sealed in by multiple protective layers. Going by both the manufacturer's data and the history of panels installed like this (multiple boats over several years) they seem reliable and long-lasting like rigid panels, certainly far better than the flexible panels often used.

 

The downside is that they're much*** more expensive and the installation is critical and really needs doing properly when the boat is built, it would be very difficult to do afterwards.

 

*** far too pricey for most people installing DIY solar, but maybe 1% extra on the cost of a new boat so I think they're worth it... 🙂

Edited March 10, 2023 by IanD

[magnetman]

It will be interesting to see how you get on with them.

 

My suggestion is probably a bit impractical yes but it can work if the boat is not often going anywhere.

 

My LG 355w panel is 1686mm long which is not much over the dimension you mentioned above for width of cabin top.

 

 

It is also all black which is aesthetically pleasing.

If you lifted this up by 4 inches using stands on the cabin top the handrail would be available, air under the panels (they work better when not hot) and space for mushroom or ventilites in the cabin top underneath them. I also think this arrangement could potentially result in a cooler cabin due to the insulating effect in summer.

 

Run a load of plastic hoses up and down underneath and you could probably also get hot water in summer.

 

Doesn't seem to terrible.

LG 355w

 

Weight: 18kg. Dimensions: 1686 x 1016 x 40mm. Warranty on output: 25 Years Linear Warranty. Product warranty: 25 years.

 

So if one had 10.16 metres of cabin top to play with that would be 3.55Kw of installed solar panels.

 

 

[ditchcrawler]

3 hours ago, magnetman said:

You could fit wider rigid panels and elevate them by a few inches to allow hand access to the cants if needed and give room for cabin top ventilators under. I would not have a centrally fitted centre line it would be on a bridge in the cant handrail or even better have circular tube handrails.

 

I know it would alter the profile of the boat slightly to have solar sticking out and more attention needed at bridgeholes and tunnels but depending on how regularly the boat is moved and where it is used it would be doable. Not particularly sensible but as I mentioned this sort of thing will be about priorities.

 

I hope those flexible panels last alright. Not keen on them myself but they do look better than the rigid ones on a narrow boat.

 

 

 

 

I met a boat like that escaping London late on in Covid, At every bridge hole he had to adjust the panels to clear it as the boat slid through

[IanD]

2 minutes ago, ditchcrawler said:

I met a boat like that escaping London late on in Covid, At every bridge hole he had to adjust the panels to clear it as the boat slid through

Of course if you don't want to move the boat you can get a *lot* more panels on it -- down the sides, standing up on the roof, tiltable and attached to masts like a squarerigger -- then they can rotate to face south too... 😉

[ditchcrawler]

8 minutes ago, IanD said:

Of course if you don't want to move the boat you can get a *lot* more panels on it -- down the sides, standing up on the roof, tiltable and attached to masts like a squarerigger -- then they can rotate to face south too... 😉

When I was moored at Park Farm neat Anderton a boat there had the side as well as the top covered, I don't know if it was both sides as I never saw the other side.

 

A full roof of panels 

 

The is a square rigger

 

[IanD]

17 minutes ago, ditchcrawler said:

When I was moored at Park Farm neat Anderton a boat there had the side as well as the top covered, I don't know if it was both sides as I never saw the other side.

 

A full roof of panels 

 

The is a square rigger

 

A proper square rigger would have at least three masts, with at least three panels on each. *Massive* solar power... 😉

[magnetman]

A reet bugger for the bridges. 

Yars ago I had a wind turbine and on the pole was an adjustable solar panel (75w was £350 in those days). 

 

too annoying for a cruising narrow boat. 

[IanD]

10 minutes ago, magnetman said:

A reet bugger for the bridges. 

Yars ago I had a wind turbine and on the pole was an adjustable solar panel (75w was £350 in those days). 

 

too annoying for a cruising narrow boat. 

 

But not one that doesn't... 😉

 

Once you've got 2kW of panels on a narrowboat (which isn't too difficult), there doesn't seem much point busting a gut and accepting significant inconvenience to squeeze a bit more in -- even another 50% (3kW) still isn't going to give you enough power in the depths of winter.

 

So you'll still need to have a generator (or to run the engine) anyway, all the extra kW does in return for the pain is give you maybe an extra month or two generator-free -- you'd need at least 5kW of panels to avoid this entirely (solar only) and this is only possible on a wideboat.

Edited March 10, 2023 by IanD

[magnetman]

Perhaps it would fulfil the 'reasonable in the circumstances' loophole in the '95 act I don't think. 

[MrFish]

4 hours ago, magnetman said:

It will be interesting to see how you get on with them.

 

My suggestion is probably a bit impractical yes but it can work if the boat is not often going anywhere.

 

My LG 355w panel is 1686mm long which is not much over the dimension you mentioned above for width of cabin top.

 

 

It is also all black which is aesthetically pleasing.

If you lifted this up by 4 inches using stands on the cabin top the handrail would be available, air under the panels (they work better when not hot) and space for mushroom or ventilites in the cabin top underneath them. I also think this arrangement could potentially result in a cooler cabin due to the insulating effect in summer.

 

Run a load of plastic hoses up and down underneath and you could probably also get hot water in summer.

 

Doesn't seem to terrible.

LG 355w

 

Weight: 18kg. Dimensions: 1686 x 1016 x 40mm. Warranty on output: 25 Years Linear Warranty. Product warranty: 25 years.

 

So if one had 10.16 metres of cabin top to play with that would be 3.55Kw of installed solar panels.

 

 

Sadly i thing LG have stopped making solar panels some time near the end of last year.