Installing Electricity On Small Yacht

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FARP

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Dear All,

My first post on this Forum but speaking to a few friends it is apprently a fine source of knowledge.

My situation is this: I have a small 24ft yacht which is used for day and weekend crusing and racing. Currently there is no power onboard. I'd like to install fix tri-colours, a heater (not too keen on charcole but haven't heard much about electric heaters either) and a small stereo.
I've been reading previous posts and the general picture seems to be that the Kipor 1000Ti would be up to the job, but could anyone recommend a marine battery and a charger for such a gen battery combination?
It's a long time since my physics A-Level and I'm just hoping someone can help me out rather than have to dive into my out school books!

Many thanks in advance!

FARP /forums/images/graemlins/wink.gif
 
It is not clear exactly what you want to do with the heater.
Some heaters take a lot of power even if it runs on diesel some need power for a fan. So first simplest solution is to take a fan mains electric heater and plug it into the shore power when the boat is in it's berth. ie no mains power no heating.

You could go down the path of gas heater, some don't need a fan, but the compllexity of a safe legal gas installation means it is not worth goinng that way. (Though many do)

So a charcoal or wood fire is one option. Or you might consider a alcahol (Methylated Spirit) cooker and hope that will warm the cabin a little.

The 12 volt electrics (I assume you have none at all) depend on the charging power available. It sounds like you have no engine so no engine driven generator. Many outboard enginnes can not charge very usefully but you should explore that avenue.

If you have shore power then a charger connected either full time or just occasionally will do the job. If no shore power then you could use a battery that is light enough to carry home for recharging. You could go for a smaller car battery or a Sealed Lead Acid type which have vaying sizes down to 2 amp hour that will fit in a big pocket.

So how much power do you need? Nav lights will typically draw 1 amp and a stereo about 1/2 amp. You might want a VHF 2way radio for safety drawing another amp when on receive. So you total the current you need and multiplly it by the hours you want to operate before recharging. So do you want to be able to sail right through the night or just for a few hours lights on for a late return in winter? Will voyages be limited to 4 or 5 hours. Obviously you can only make a guess and you can extend battery time by not using stereo for innstance.

The current multiplied by the hours is called Amp hours. It is effectively the fuel you need from your battery. However you need a battery rated at about twice what you expect to actually need. You can get more out if the battery is new and good but discharging a battery completely is not good for them.
My guess then is that a battery of about 30 amp hour might suit you. This is a small car battery or mid sized SLA battery. Note car batteries are not good for deep discharging but are so cheap by commparison to heavier marine batteries that I think they are a viable option. Some will say buy them from a motor breaker really cheap.

You need to be able to house the battery clamped down and covered so it will not dislodge in a knockdown and so metasl can't fall on the battery to short the terminals.

The wiring should consist at minimum of a single fuse near the battery and switches for the lights. You could rely on the stereo power switch if the battery is to be taken home for recharging and not left connected in your absence. You will aslo want a cabin light with switch.

There are other options for battery charging. My boat is very similar and I rely on solar panel to charge the battery. I have a 14 Amp hour wet NiCad battery but these are expensive. The solar panel is quite small about 5 watts but it takes a couple of weeks to recover from an evening (lights on) sail and that is in Oz summer. You should use a larger panel. I attach mine to the boom with bungee cords when I leave the boat on swing mooring. You could also use wind power but I imagine that would be tooe xpensive for what I imagine your needs are.

Good luck PM me if you want more details... olewill
 
Hmm. depends what you want to achive and at what cost. Have you got shore power and is this where you want the heat. If you have shore power, it's simple to conect a lead and buy a fan heater for £20 or so. If not, it's hard to produce enough electicity to heat the boat that way, but could install a diesel heater, or gas, dependant on system, you may still require a fair amount of electric, which could be suppled by genny to batteries. Batteries, chargers and heating come in a multitude of prices. Depends on the sofistcation you want.

My original method of cooking was a camping meths stove. Maybe ten quid. My cooking/ heating / elecric system now is probably worth about five grand to replace.

Maybe buy a small genny from B&q 50 quid, a battery leasure. umm 25 quid, bit of lead and plugs. Battery charger maybe 10 quid. Fan heater, but then need shore power or a hell of a generator.
 
In addition to the comments above..

I have a 24 foot sailboat that is used for weekend cruising and sometimes for extended cruises for a few weeks. We have a Wallas paraffine heater that is rarely used. We also have an Origo meth stove. There is simply no way you could use batteries to heat a sailboat, so skip that /forums/images/graemlins/smile.gif

Other main consumer is the cooler, a compressor-driven box. Drain from VHF and instruments is negigible and we rarely sail at night.

We have a 110Ah car battery which is charged from a "24W" solar panel and it has worked out well over the years. The panel keeps the battery fully charged whilst the boat is not used and the large capacity of the battery gives us some margins for cloudy days.

So basically what you need is:
A battery, as large as possible.
A power source. Either a switched-type charger if you have shore power or a solar panel. The panel has the advantage of making you independent of shore power. Disadvantage is to fit it. I have mine aft so that I can adjust it during the day for maximum sun.
Minimise consumption - Use LED lanterns, reading lights etc.
 
Thanks guys,

Some really usefull info there from everyone. It seems that this is one of those scenareos which has more than one answer. I think I'll have to go away and crunch some numbers now.

Interesting that none of you went down the small silent generator path. Noted.

Cheers again guys.

Happy sailing.
 
I have a 23ft boat with a fairly large (maybe 80 AH) leisure battery. It runs Nav Lights (3 plus mast head) Cabin lights 1X20W, 2X10W rarely all on at once. VHF, GPS (handheld) when plugged in.

It is charged by a 10W solar panel and charging coil on my outboard, the output which maybe developes 3 or 4 amps at high revs.

It does us alright for our normal cycle of every other weekend on the boat but it has a nett drain at the end of a week or so continuous use. I would have used a marina mains supply to recharge. (had I remembered the charger)

It you do do your boat make sure the cables are large enough. I intend to replace the cable between my battery and fuse panel (about 3.5Metres) which is standard 2.5 mains flex with something more substantial at the voltage drop when I transit is dimming the lights quite a lot. I would not use anything less than 2.5MM for any circuit and I would try and use marine grade cable.
 
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