Power generation

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dnickj

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How best to produce electricity ??

we are planning to live on he boat next year - currently 2 x 110ah batteries (domestic ) will add at least an additional 1 of the same rating

currently just shore power and the engin alternator to charge
and i dont want to run this just for charging

SWMBO wants a nice new deisel genny installed - with power at the flick of a switch - Im not so sure

would wind and solar be the better way to go - with a honda petrol genny for when she realy needs the hair dryer ??

All ideas would be greatfully received but i will need good reasons to convince her !!!
 
I am saving up for one of the new generation 12 volt cocooned diesel charging generators with an inverter for supplying the mains power. The generator starts automatically when the batteries are low but doesn't need to run just for boiling a kettle or warming something in the microwave or such-like. This seems to be the best of all worlds if you don't need electric cooking.
 
I lived aboard for three years (in Hong Kong). The most unreliable item of equipment aboard was the diesel generator, which I had installed new. On the other hand the back-up Honda generator (2.4KVA from memory) started first time - even after standing idle for six months. Most of the other live-aboards I knew had problems with diesel generators.
I travelled a lot on business and Sod's law dictated that the problems would occur when I was not there. Endless telephone calls from SWMBO and hefty yard bills. In the end she insisted on moving ashore.

So I am a great believer in KISS. For the price of the diesel gennie I could have installed an almost infinate area of solar panels and a large battery bank say 500AH at 24volts. That's the way to go IMHO.

However I see ads and press releases for marine fuel cell systems which I would be tempted to try out - even if it meant being an early adopter.

So to answer your question tell your SWBO that life is much more relaxed if you keep things simple. Point out what you could do with the money you save by not buying a diesel genny.

That's my five cents worth anyway
 
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How best to produce electricity ??

we are planning to live on he boat next year - currently 2 x 110ah batteries (domestic ) will add at least an additional 1 of the same rating

currently just shore power and the engine alternator to charge and i don't want to run this just for charging

[/ QUOTE ]

Why would you need a generator if you have shore power?

Have you worked the cost of purchase, install, service, consumables and fuel?

We have twin engines with their own batteries for starting, the engines alternators charge them and nothing else; we also have 3 large solar panels 1 x 80 watt and 2 x 60 as well as a high tech multi stage charger that runs off the mains when in the marina.

We have 6 x 6 volt house batteries all very large high capacity jobs charged by the solar panels and shore power, and run 2 fridge freezers 24 / 7 plus a large Engle portable fridge when out fishing and have never had a power problem.

If you plan to live aboard and have a mains supply stick with it would be my advice, cheaper and far more reliable and no noise or fumes for you or others to put up with.

Avagoodweekend......
 
I am not planning on spending all my time in marinas - and its hard to plug in whilst at anchor in a secluded bay
 
Depends on what you want to do with it. demands could be as minimal as lights, hifi and sailing instruments/nav lights. How long are your trips away from the shore power going to be? just an overnight trip round the corner or a transat?! If the former, you probably can survive with nothingin addition to what you have! of course, if you want all mod cons and want to be self-sufficient for a number of months, then you'll probably want to think in terms of a combination of things - wind, solar, engine alternator, possibly a towed water generator, coupled to a pretty hefty battery bank... and maybe even a genny. They seem more trouble than they're worth to me, but I'm another KISS subscriber.

Need more info to be more specific, but I guess form your comments thus far you're inclined towards creature comforts rather than rugged simplicity.
 
Away from shore for 2-3 weeks at a time running lights - plotter instruments - fridge etc - I would like to keep it simple but she wants comfort - there must be a middle ground
 
argh, the F word! fridges eat a lot of power so will push up the amount you'll need to generate. for 2-3 weeks you'll basically need to be able to gereate everything on board some how, so shore power sort of becomes academic. how much do you motor? if you're in the habbit of motoring often when you don't HAVE to, you may find that you can keep the bateries topped up with the engine, and apparently a 'smart charger' will improve the charging effectiveness of the alternator. If you're covering a lot of sea miles and don't stop for very long at a time, a towed generator could be a good option. you can get the benefits of both wind and towed with the Duogen I think. I have the D400 which is the same generator and 'air' blades, but the duogen also has a log type spinner (I think). That serves my needs plenty, and should cover a fridge when I get round to installing one... combined with a bit of solar that might do the trick, but you need to do some number crunching:

write down (excel is good for this) all the appliances you have/want, thier power rating and service time, and tot up the Wh per day (1/1000 of a domestic unit)(divide by 12 or whatever you system voltage is to get the Ah which some people prefer to work in) This is the ENERGY you need to cover on a daily basis...

do the same for every item that gernerates electricity, but here its more complex because you need to know average wind speed, sunshine hours etc... whereupon you realise that actually the weather changes quite a lot... so you'll need a battery bank to cover, say three of four days use (i.e. 3 or 4 times the daily Ah- that'll probably come to a lot more than your 220 installed). But you can also top up in an emergency with the engine... but you might prefer to invest in oversizing your turbine/solar arrangement so you don't have to do this. Remember the flow of energy used must be matched by the flow of energy generated (plus some) - no quantity of batteries will allow you to get away with using more than you generate.

I've just tried to explain something quite complicated in a very small space, so sorry if it's unclear!

Note on fridges - they have to work harder the hotter the climate you're in. If you haven't got one already, experiment with doing without, it's very liberating! milk etc goes in the bilges and will keep surprisingly long, buy meat on day of cooking (or go veggie!). The only thing I miss without a fridge is a cold beer...
 
Jack-Sparrow.
It is a generator more or less identical to a normal mains genny, except it is smaller lighter and a little cheaper and drives a high output 12 volt alternator to automatically keep the batteries fully charged.
Fully cocooned, water cooled etc. and only needed when the batteries are down not everytime mains is required like a normal genny. Several genny manufacturers are now offering them.
 
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Several genny manufacturers are now offering them.

[/ QUOTE ]I looked into these recently. The attraction is that the engine speed can vary to suit the load, making them potentially very quiet. However, several companies which did offer them have discontinued them. The only decent one I found was the Fischer Panda one at around £10K. Do you know of others?
 
The original question is difficult to answer. As said it depends on how long you are away from mains and what you are prepared to put up with when away for lack of power.
I reckon that you could be very comfortable with a 12 volt fridge and a smart charger on your engine driven alternator (gen) for those times when you are away.

However many people around here have the big Mobo for weekends away at Rottnest Island. They have the diesel 240V AC gen fitted and from there it is easy/ cheap to make everything domestic run on 240V AC including cooker, microwave and fridge. All relatively cheap being domestic. No gas concerns.

So if you make the decision to go generator then forget solar panels, inverters gas cookers etc. I certainly wouldn't consider a 12v system from a gen, the current for any real power is just too much.

So either slum it with 240V shore power and roughing it away from the marina or go all out 240V Ac for everything with a gen.

good luck olewill
 
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I certainly wouldn't consider a 12v system from a gen, the current for any real power is just too much.

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Our Fischer Panda has a maximum charging current of 280amps. The inverter is 2.5KVA and will start the AirCon/Heating from the batteries or run the water heater anytime.

If you go for the DC option and an inverter you'll need a big battery bank, ours is 1050Ah.

Use the SEARCH ENGINE and you will find lots on this subject.

I also believe in the KISS principle - Keep It Supremely Sophisticated - especially if you are living aboard and still want home comforts.
 
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