'lecktricery for liveaboards

[Alastair]

I used to liveaboard and have owned 4 very different types of boat (from small sailing yacht - narrowboat - dutch barge).

Most of the boats had 12V or 24V lighting. Simple to maintain, simple safe fuses, it seemed sensible.

Three of my boats just had a very simple system for 240VAC appliances - I just used a small inverter and a single extension lead, suitable earthed. This seemed simple and easy.

Then we got the big dutch barge (20m, 5m beam) and started making alterations and looking into adding exotic things like hot water and heating. Very quickly I realised that DC fittings and appliances (particularly things like pumps) are very expensive. They are also, compared to common domestic 240VAC fittings, not very durable! Liveaboards make very heavy use of fittings such as lights. I was forever replacing halogen bulbs, experimented with LED fittings etc. Voltage variations etc took a heavy toll. At one end of the boat bulbs would be bright, at the other they were so dim. Wiring in a pump meant buying heavy cable to avoid voltage drop (it's bad for pumps to run them under voltage).

The real kicker was when we looked into installing a diesel boiler. DC-powered burners were damn expensive and the dutch barge association members had many tales to tell of pumps failing.

We already had a 1.4kW inverter and distribution board. So I did my reading, efficiency calculations and put in two new ring mains. A domestic boiler was purchased and installed - 1/3rd the price of a 'marine' boiler. Halogen 24VDC lights replaced with GX53 CF - the same size and just as compact but much much brighter. More corrosion and bash-resistant as well!

Suddenly I was no longer buying spares from expensive chandlers, but could get them (when rarely required) from any hardware. Parts for almost everything were cheaper and (dare I say it) better made and more durable than 'boat' fittings.

I'm unlikely to fit out a boat from scratch or even do a major refit again. But if I were, I wouldn't bother running DC round the boat. Fit a half-decent inverter, a domestic consumer unit and a 240VAC ring main.

For those quite evenings when the stove is emitting a gentle glow through the bars, all the electrics will be off and I'll light a shining brass paraffin lantern. That's not practical at all, but the light is certainly pretty.

[Doodlebug]

Thats not a bad idea but means you need extra input to account for the inverters losses. Also you need to then be careful to only buy low wattage stuff for the boat. Its easy to get carried away.

 

We have a 300w inverter and although its a relief to not rely on 12v things all the time, its easy to get carried away. The latest purchase was a twin tub washing machine. But eventually we want a dishwasher. I have to keep reminding myself I need enough power to run these things though.

[smileypete]

For a large boat it's also got to be worth considering worth going to 24V.

 

Some good deals can be had on the 24V versions of the big kit like alternators and inverters, and for the little stuff you can also use 12V DC items with a DC step down converter, which can be had for buttons from Ebay these days. The converter will also give a stable output so the supplied item doesn't have to cope with high charge voltages and voltage spikes from the alt.

 

cheers, Pete.

~smpt~

[nb Innisfree]

Once you get a large efficient inverter such as a Victron or Mastervolt with a proper sized battery bank and alternator the world is your oyster.

[OldGoat]

If you are going to install a lot of 240V equipment, you really should consider installing a mains generator to power the cooker and washing machine. Even so you need a large battery bank to run a big inverter for domestic sized uses.

12V is too low a voltage for high current applications. 24 or even 48V is better.

I'm bound to be rubbished, so I won't expand further for now.

 

One thing I will say is - why do folks expect to be able to translate land based living into a small scale marine environment (If you have a monster yacht, then you also have a small power station in the bowels of your "palazzo di grappa". Doesn't really work on a NB or a small broadbeam boat.

[ditchcrawler]

If you are going to install a lot of 240V equipment, you really should consider installing a mains generator to power the cooker and washing machine. Even so you need a large battery bank to run a big inverter for domestic sized uses.

12V is too low a voltage for high current applications. 24 or even 48V is better.

I'm bound to be rubbished, so I won't expand further for now.

 

One thing I will say is - why do folks expect to be able to translate land based living into a small scale marine environment (If you have a monster yacht, then you also have a small power station in the bowels of your "palazzo di grappa". Doesn't really work on a NB or a small broadbeam boat.

So true

[bargemast]

If possible, adapt your requirements as much to the KISS systems as you can, that way you'll have less expensive surprises.

 

What you don't have can't break down, or need repairs.

 

Peter.

[sueb]

12v is ample :-))

[tafelberg]

Tafelbergs systems are brilliant, although it's only the Cat and I. I have 3 batteries and one starter that can be charged via engine and I have two 85watt solar panels, in the summer, I hardly run my engine as when I'm at work it all charges up and there is more than enough power on the 240v system to run my Mac, my ipad and TV, it's fantastic.

[Robbo]

 

The real kicker was when we looked into installing a diesel boiler. DC-powered burners were damn expensive and the dutch barge association members had many tales to tell of pumps failing.

 

Looking at doing the same thing, looking at a Bubble PJ for the boiler which is 240v - which boiler did you end up going for?

Edited May 24, 2013 by Robbo

[blackrose]

I really don't understand why anyone living on a boat would want only AC electricity? You want to get up in the night to go to the toilet and you've either got to switch on the inverter to get some light, use a torch, or just have a piss in the dark!

 

Anyone who's lived on boats for more than a few years knows very well that you try never to rely on one system for anything, because if that system goes down you're screwed. What are you going to do if the inverter stops working for some reason? Properly installed DC systems are fine and once fitted they aren't that expensive. I don't know what the OP is doing wrong but I don't have to constantly replace light bulbs.

 

I have AC and DC systems on my boat, 4 different heating systems, 4 different wats of getting hot water, a mains and a car stereo, a mains and a small 12v TV. A 3 way fridge. If all my lights fails I even have a paraffin lamp. There's no reason to depend on single systems on a boat.

Edited May 24, 2013 by blackrose

[Trento]

If you are going to install a lot of 240V equipment, you really should consider installing a mains generator to power the cooker and washing machine. Even so you need a large battery bank to run a big inverter for domestic sized uses.

12V is too low a voltage for high current applications. 24 or even 48V is better.

I'm bound to be rubbished, so I twon't expand further for now.

 

One thing I will say is - why do folks expect to be able to translate land based living into a small scale marine environment (If you have a monster yacht, then you also have a small power station in the bowels of your "palazzo di grappa". Doesn't really work on a NB or a small broadbeam boat.

All my three boats, 2 x NB and one Dutch Tjalk, have all been 24v and permanent 240AC ring mains, supplying domestic "white ware". The OP is absolutely correct in his evaluation.

Sufficient good quality, deep cycle batteries, plus, in my case a 24v. 3000watt inverter makes for easy living...with replacement items (non thus far after 3 years) cheap and off the shelf.

[Paul C]

If you are going to install a lot of 240V equipment, you really should consider installing a mains generator to power the cooker and washing machine. Even so you need a large battery bank to run a big inverter for domestic sized uses.

12V is too low a voltage for high current applications. 24 or even 48V is better.

I'm bound to be rubbished, so I won't expand further for now.

 

One thing I will say is - why do folks expect to be able to translate land based living into a small scale marine environment (If you have a monster yacht, then you also have a small power station in the bowels of your "palazzo di grappa". Doesn't really work on a NB or a small broadbeam boat.

 

Putting the argument for/against using mains devices + inverter aside for now; I agree that 12V isn't ideal for a narrowboat and I'm surprised that not more boats, especially newer boats, haven't standardised on 24V wiring. If you look around at 12V electrical devices, there is little out there which isn't either also available in a 24V version, or is designed to work on a wide voltage range so it would already work on 24V.

 

If I ever win the 'lotto' and get to commission a new, perfect-for-me, narrowboat, I'd be specifying 24V from the outset.

[oarfish]

Putting the argument for/against using mains devices + inverter aside for now; I agree that 12V isn't ideal for a narrowboat and I'm surprised that not more boats, especially newer boats, haven't standardised on 24V wiring. If you look around at 12V electrical devices, there is little out there which isn't either also available in a 24V version, or is designed to work on a wide voltage range so it would already work on 24V.

 

If I ever win the 'lotto' and get to commission a new, perfect-for-me, narrowboat, I'd be specifying 24V from the outset.

 

Finding a 24V water pump on very short notice in the middle of nowhere with no car was fun.. I now know to keep a spare.