Learning to cope without shore power

[SteveSarabande]

At the moment I have access to shorepower at the marina, but I am looking to move to a pontoon berth without electrics. I am interested in how others cope without electric for battery charging.

I only have a 2 battery system, no installed shorepower setup, I just use a small charger and an extension lead to recharge them. I do stay onboard at weekends and then use the electric fan heater in preference to the eberspacher.

Do people just use the engine to recharge their batteries or should I be looking at solar to recharge during the week. Is it worth installing a more intelligent regulator from the alternator?

Its a 27' yacht, with two 85ah batteries, used all year.

 

[Pye_End]

Unless you want to run your engine regularly, then a solar panel sounds a good idea. I fitted a 40W last year for other reasons, but find it tops the batteries up sufficiently to run the Eber for a couple of hours a week, and havn't used the shore power for yonks.

 

[SteveSarabande]

I guess a battery upgrade might be usefull too, combined with a solar setup.

For sailing it probably isn't a problem, it's more at weekends, running the eber and power tools for the diy projects. Cabin lights are all led so that saves some battery.

Time to search through the hundreds of solar posts on here.

 

[duncan99210]

Before you do anything, do an audit of how much power you're likely to use during a normal day moored up and a normal day sailing. This will giv eyou how much power you need to generate in order to keep pace with demand. You can then look at the various methods of generating the power: main engine, small generator, solar, wind etc etc. Look at the costs and simplicity of each system and you may well decide that the easiest thing to do in your case is simply to run the main engine for a couple of hours a day, as and when required. We didn't fit solar panels to Rampage until we'd been cruising for a couple of summers, relying on the main engine for most of our generation. Even with the panels and in the med, we still need to run the engine a bit every couple of days to keep up to pace with demand.

 

[chinita]

+1.

But then, I do not use any power other than if starting the engine!

Oil lamps, candles, Vapalux, Laphroiag, dog, SWMBO - enough to keep me warm

 

[wotayottie]

Do people just use the engine to recharge their batteries or should I be looking at solar to recharge during the week. Is it worth installing a more intelligent regulator from the alternator?

Its a 27' yacht, with two 85ah batteries, used all year.

It all depends in my experience on whether you have a fridge - its the one piece of kit on board that munches through the amps. I am on a swinger in summer. Without the fridge my 35 watt flexible solar panel keeps the batteries up to scratch though its a bit marginal if I use lots of lights etc. With the fridge in use the solar panel hasnt a hope. I am about to try a windmill but am not hopeful based on the data I have seen. Without it I need to run the engine every 36 hours and for at least an hour a time. And thats with a 60 amp alternator and a smart regulator.

My fridge alone gets through 50aH per 24 hours. Best I have seen out of the solar panel is 2 amps and thats at midday. With 12 hours of darkness I doubt it manages more than 10aH per day. Work that calx backwards and I need something like two big 100 watt panels just to keep the fridge going. Not feasible on a 35 footer without some sort of ugly great gantry.

As I say I am trying a windmill but I fear that the only real answer is a built in diesel generator.

 

[ghostlymoron]

If you haven't got a fridge, you should have no problems with generating enough solar power. The main problem with lack of fridge is the 'milk' question. Even uht goes off overnight in summer once opened although it will store indefinately unopened. I always keep a supply of powdered - shop around - most is skimmed which is very watery and unpleasant. There are some brands which are full fat which are much better and worth seeking out.
In winter, the problem is powering your eberspacher which draws a huge current when starting. I believe Propex gas heaters are better in this respect.
I would definately consider uprating your house battery to 110ah. I've read a lot of 'battery' threads recently and the useable power in a battery seems to be only half the rated capacity.

 

[prv]

KS was fitted for shore power, but there was none on our berth so when the battery charger packed up I never quite got round to replacing it. The only charging is the engine. We do have a fridge, but no other major consumers (plotter, incandescent lights, etc).

By and large, normal motoring in and out of places seems to keep up with consumption - and I am not one for motoring when I could possibly sail. On the rare occasions that I spend a couple of days moored up with the fridge running but without going anywhere (generally forum meetups!) the remaining capacity can drop lower than I'd like.

Since it's obviously important that my engine charging be as good as it can be, I followed Gibbo's advice here. The alternator is wired directly to the service battery, interrupted only by a large fuse in case of a short in the engine bay. A large relay controlled by the Smartgauge parallels in the engine battery for charging, when the engine is running.

It sounds like you have slightly higher loads (eberspacher etc) so solar sounds like a good idea. Our new boat has more toys, there's still no power on the berth, so I think some flexible panels on the coachroof will be making an appearance at some point.

Pete

 

[ianj99]

I guess a battery upgrade might be usefull too, combined with a solar setup.

For sailing it probably isn't a problem, it's more at weekends, running the eber and power tools for the diy projects. Cabin lights are all led so that saves some battery.

Time to search through the hundreds of solar posts on here.

Battery upgrade only if your solar panel is big enough to charge it between visits or you end up with a permanently under charged battery which is not good for it and no use to you.

Alternatively, when you stay for longer, just bring another battery from home, which is kept on a trickle charger and take away when you leave.

 

[SteveSarabande]

Demand in winter is obviously higher than summer. I am the boat as a caravan two nights a weekend while doing maintenance. LED Lights, eber, netbook/phon charging.

This will get better in summer, less eber, more sailing so more engine running. I will work out a consumption chart. Bigger batteries are on the shopping list, these came with the boat and are pretty old. Maybe it is the worn out batteries that are causing the short time i get between charges at present.

Will a smart regulator on the alternator make a big difference?

 

[ghostlymoron]

Flexible panels - prv

It sounds like you have slightly higher loads (eberspacher etc) so solar sounds like a good idea. Our new boat has more toys, there's still no power on the berth, so I think some flexible panels on the coachroof will be making an appearance at some point.

Pete

PRV, I have semi flex panels which I believe have a higher output than the fully flexible ones. They take up the curve of the coachroof well and can be walked on although I avoid this if I can.
Incidentally I've heard of a new generation of domestic panels that are combined PV and thermal. The output of a PV panel is higher if it is kept cool so these have a water jacket to optimise the electrical output, the heat from the water jacket is used to heat domestic hot water. Not much use on a boat but worth considering on your house.

 

[prv]

PRV, I have semi flex panels which I believe have a higher output than the fully flexible ones. They take up the curve of the coachroof well and can be walked on although I avoid this if I can.

Yep, those were the kind I had in mind. I think there's space on the coachroof between the mast and the forehatch, which will rarely be walked on. Not keen on big stern gantries etc for aesthetic reasons.

Pete

 

[V1701]

I have 60w of solar (a 40w semi-flexible & a 20w panel), they charge 2 x 110AH batts enough to power lights (all converted to LED) & charge netbook, mobile, HH VHF, even watch a bit of TV on a tiny 10" 12v TV, but I don't have a fridge or a blown air heater. Albin Vega 27ft...

 

[vyv_cox]

As you have learned from the posts above, you are standing at the top of a long slippery slope. In the simplest terms you ideally need an alternator regulator, bigger domestic batteries, a wind generator or good sized solar panel, because a small solar panel will probably not charge deeply discharged batteries in five days. This will require its own regulator All this to give you comfortable warmth for the weekend.

For many years we kept our various boats on a swinging mooring and did not even have any mains wiring. We used a catalytic heater for all our heating requirements, very effective. Despite what many people who have never used one will tell you, these heaters produce very little more condensation than your breathing does. I wouldn't run one overnight but a decent sleeping bag will easily cope with UK winter temperatures.

Otherwise, running the engine will replace the small amount of power you will use for lighting and other small needs. An alternator regulator would be the first thing I would add, as it will extend the life of your existing batteries.

 

[AngusMcDoon]

If you do have a fridge and want to continue having refrigeration then a Waeco 18 litre CF18 uses about 10Ah per day even in summer. They might not be cheap but it's cheaper to use less this way than install more generating capacity.

 

[alteredoutlook]

If you haven't got a fridge, you should have no problems with generating enough solar power. The main problem with lack of fridge is the 'milk' question. Even uht goes off overnight in summer once opened although it will store indefinately unopened. ]

Have you tried the 'evaporation fridge' - place items in a sealed plastic box, wrap box in damp cloth. The damp cloth dries and extracts heat from box. Cheap, doesnt break down. I used it for a year on the atlantic circuit and it kept my butter from melting in the carribean.

 

[aquaplane]

I seem to cope without 240V and the alternator refuses to work much of the time.

If you don't want the expense and kerfuffle associated with smart chargers/solar/windgen just accept that you can't have a fridge (except a cool box with party ice in) and go to bed when it gets dark.

Early and late season I sometimes have to take a battery home between visits so that we have enough juice to run the Wallas but that's a minor inconvenience to me.

It wouldn't suit everyone but it works for us.

 

[VicS]

....
We used a catalytic heater for all our heating requirements, very effective. Despite what many people who have never used one will tell you, these heaters produce very little more condensation than your breathing does...

They will produce the same quantity of water vapour, and therefore potential condensation, as a non-catalytic heater for the same heat output/quantity of fuel burnt wont they ?

 

[vyv_cox]

They will produce the same quantity of water vapour, and therefore potential condensation, as a non-catalytic heater for the same heat output/quantity of fuel burnt wont they ?

I assume the water vapour is directly related to the mass of fuel burnt. Whenever the subject is discussed here there seems to be an assumption that the sides of the boat will resemble a waterfall due to the vast volumes of water created. My experience is that these heaters are frugal in gas consumption and that condensation resulting from their use is pretty much unnoticeable.

 

[Lodesman77]

I assume the water vapour is directly related to the mass of fuel burnt. Whenever the subject is discussed here there seems to be an assumption that the sides of the boat will resemble a waterfall due to the vast volumes of water created. My experience is that these heaters are frugal in gas consumption and that condensation resulting from their use is pretty much unnoticeable.

+1

I would second this; was on the boat a couple of days ago in very low outside temperatures and (as usual) didn't find any particular condensation issue...

To the OP: I have a 28ft boat on a swinging mooring, so same issues you will have. I have a 105Ah house battery, a 36W solar panel and a smart alternator controller. I find the panel alone will recover a half-discharged battery from one weekend to the next in the summer, but just about maintain charge in the winter. Normal engine use is sufficient for most charging requirements but you need to have a long trip under motor occasionally to get the most out of any smart charging capability.

For heating I take a multiple source approach - I have a small propex which is good when I have plenty of battery power available, and draws less then an eber type. I have a catalytic heater which is for when I don't want to use battery power. Then I have a vapalux parafin lamp which gives another kw or so of heating capacity.

In the winter, if I want to do power tool type DIY I go into a marina for a night or two...

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