How much solar do you have?

[geem]

Thought it might be interesting to see how much solar people have and where they locate it. Over here in the Caribbean, lots of boats have a solar arch, but many also mount panels on the guardrails.
Starter for ten. We are liveaboard on a 44 ft ketch. 4x180w solar panels on the guardrails with an additional 200w of roving panels giving us 920w of solar on the domestic bank. We have a dedicated 40w panel that looks after our engine batteries.

 

[William_H]

I managed for my little boat with 5w of panel charging a Nicad battery for occasional radio and lights use. Quite adequate in fact I often left it disconnected. (no controller) But that is an extreme case in sunny climate and only for summer season. Panel sits on top of main sail cover with bungees.
Actually solar panels are relatively cheap compared to cost of mounting them and indeed finding as place to mount them. So if I was a live aboard I would have as much as mountable. Meanwhile have had 1500w at home PV system for 11 years. Paid for itself no problem. ol'will

 

[Kelpie]

1150w total.
2x260w overhead as a bimini, 2x100w on guardrails, 2x100w on foredeck. Giving a total of 930w feeding the lithium.
A further 2x100w on the bimini, and an old 30w on the hatch garage, feeding the lead acid system. Which is overkill given how little work that system does, but you have to be nice to your lead acid and keep them full.

We mostly cook using electricity, and have no way of charging the lithium from the engine. In the Med this setup gave a lot of excess power, here in the Caribbean it's a bit tighter due to cloudy days, bit still works very well.

 

[john_morris_uk]

A distinct lack of available space to fit solar (no arch on our boat) means we will have 440 watts total as of our return to Serendipity in November.
We could possibly add some more by mounting them on the Bimini but even 240 watts more or less keeps up with demand when we’re at anchor. Every light is LED and the fridge/freezer is pretty efficient and we cook with gas.

 

[[2574]]

310W but often only deploy 220w. Summer liveaboards in Scotland. Sufficient to keep us not needing to use the genny unless prolonged poor weather. This summer so far the genny has done 2hrs service.

 

[lustyd]

2x100W flexi panels tied to the coachroof with bungy cord which can be moved at anchor. I have extension leads to place them anywhere on board either series or parallel. They keep up with normal house loads alongside a 20-30minute hot water engine run a day.

 

[Supertramp]

130W, pilothouse roof.

UK coastal cruising, cook on gas, no inverter. On a good day it will run the instruments and autopilot on passage, or keep the domestic battery topped at anchor with the fridge on.

Probably not enough in winter but I usually run the engine every few days on passage or to enter/leave places.

Edit: Found a picture. I never go on the pilothouse roof at sea and it made the wire runs short and easy.

 

[plumbob]

About to fit 120 on coach roof. Hopefully it will keep at least one fridge running whilst we're stationary for a couple of days.

 

[Crinan12]

60 watts plenty for me, pretty much living aboard in summer in Scotland - no fridge though

 

[vyv_cox]

125 watts runs fridge 24/7 in mid summer in Greece but by September we need engine charging occasionally.

 

[NormanS]

180 Watts on deck saloon roof, summer cruising in Scotland. We benefit from the long hours of daylight, but equally, there are a few driech days without enough useful light. Originally had a wind generator . Least said about, the better.
I could, and probably should, install 100 watts each side hinged on the guard rails. One thing that's stopping me is that the ideal place would be where the canvas dodgers are, with the boat's name on them. Decisions, decisions....
The biggest battery drain is the fridge, but having the fridge means that shopping trips need only be about fortnightly.

 

[Porthandbuoy]

A 10 Watt battery maintainer (2x100Ah) to keep things topped up while on the mooring. I’m struggling to find a horizontal surface for anything >40 Watts for the fridge I plan to install this winter. Now thinking of putting panels on the guardrails or have roving panels I can site where the sun shines.

 

[KeelsonGraham]

175w on the spray hood to supplement 400ah of domestic battery capacity. Just about enough on the UK south coast to run the instruments and A/P on passage and prolong our stays at anchor without having to use the engine to recharge.

 

[Refueler]

My older smaller 25ft boat has a 20W panel on pipe clips to the aft pushpit rail ... it feeds a dual output controller to trickle charge two 90A/hr Lead Acids. Its only a back-up really as usually the boat is plugged into shore power. The controller rarely changes from two green lights. I have anither same panel which I am considering fitting as well - instead of having one large difficult to locate panel.

Can be seen here on rail :

My 38ft has a 40W panel on deck ahead of the mast into a single output controller - trickle charging a bank of three 90 A/hr Lead Acids ...

This panel has signs of age but is still functioning well ...
I have a feeling - main reason it was installed - was to cover for the built in fridge ... which suits me fine ! I am considering a small clippable panel similar to my 25ft - to be on the aft pushpit adding to the output - but first I need to see how present setup fairs.

 

[johnalison]

One very expensive 36w panel on the coachroof. It is not enough to run the fridge but does extend its use off charge to five or six days and means that a long passage with plotter, radio, etc on will not produce a drain, and easily maintains the batteries when not in use.

 

[Refueler]

One very expensive 36w panel on the coachroof. It is not enough to run the fridge but does extend its use off charge to five or six days and means that a long passage with plotter, radio, etc on will not produce a drain, and easily maintains the batteries when not in use.

i think mine falls into same category ... its not like liveaboard - to maintain full at all times ... but sufficient to extend the useable time of the batterys ...

I think that sometimes the two users are not remembered and too easy to say - xxxxW needed ... when often a lot less can do the job sufficiently.

 

[B27]

50W on the backstay/propped horizonatally.
In sunny weather this more than keeps up with our fridge.
Last winter a 15W panel parallel to the backstay for float charging.

I'm looking at options to add more panels to cover both fridge and heater in cloudier condtions.

As Refueller says, the aim is not necessarily to run the whole boat on solar, it's to go sailing for say a week or three at a time and not run out of battery power.
An hour's motoring every other day should do a bit of bulk charging.

 

[geem]

A distinct lack of available space to fit solar (no arch on our boat) means we will have 440 watts total as of our return to Serendipity in November.
We could possibly add some more by mounting them on the Bimini but even 240 watts more or less keeps up with demand when we’re at anchor. Every light is LED and the fridge/freezer is pretty efficient and we cook with gas.

Swap to lithium batteries and you will get an instant leg up in solar performance. In my experience about a 50% increase in daily solar harvest

 

[Supertramp]

But doesn't swapping to lithium for domestic batteries also involve changing a lot of ancillaries such as voltage regulator, charge splitter, mains charger, solar charger? I can see the benefit, and that the engine battery can be kept separate, but it's the engine charging of both engine and domestic batteries that would need a sophisticated charge splitter?

And will lithium emergency start the engine OK?

 

[geem]

But doesn't swapping to lithium for domestic batteries also involve changing a lot of ancillaries such as voltage regulator, charge splitter, mains charger, solar charger? I can see the benefit, and that the engine battery can be kept separate, but it's the engine charging of both engine and domestic batteries that would need a sophisticated charge splitter?

And will lithium emergency start the engine OK?

It really depends on each individuals set up. Some boats with simple systems need very liitle work to convert to lithium. Converting my boat to lithium was the other end of the scale. It was a lot of work. It took me over 2 weeks full-time every day.
If you are charging the domestic bank from the alternator and still want to do that, then you either need to go with a Wakespeeed external reg and probably a new alternator or use B2B chargers.
I was really pointing out that 440w of solar effectively becomes 660w once you are using lithium.
If you go lithium, please don't buy cheap Chinese drop in replacement. I am helping somebody out who went that route. The batteries are awful. All lithium is not the same. China is the land of facades and short cuts