‘Joanie M’ is a gas free boat. We decided on this as, already suffering from a bad back, I didn’t wish to lift heavy gas bottles in and out of a locker and we’ve never been keen on gas anyway.

We have a Onan 7 kVa diesel generator and cook on electric plus washing machine and usual other mains appliances (including dishwasher which many will abhor) In the 5 years as CCers the price of diesel has doubled but, in comparing costs, you need to look at the whole picture.

Some don’t have a washing machine but will spend a fortune at the launderette, they may be running their engine for 3 hours a day just to keep batteries charged and to provide hot water. Alternatively they may use a petrol generator to provide limited power. Our batteries are always well charged and rarely drop below 70% SOC meaning that our cheap leisure batteries last well beyond the accepted 2 years.

The boat at Rugby is not only gas free but hydraulic drive with only one power source. If you have an engine failure you will lose all your domestic services. With our set-up, if we lose the engine we still have the generator. If we lose the generator we still have mains via the 3kw inverter.

Regards

Pete

Alan said
Thanks Pete, very helpful.

Generator sounds a good option. Another couple of questions, please.

Where is your generator situated and would it be easily fitted to a boat which does not have one?

How long do you run your generator per day and at what rough cost?

Can you run your generator outside the 8to8 limit?

I am reckoning on having a washing machine and I love my dishwasher (had not considered that as a possibility on the boat).

regards

Alan

Alan, sorry for the delay in replying.

Proper built-in marine generators come in either high speed (3000 rpm) and low speed (1500 rpm) You want low speed, they are quieter both exhaust and mechanically, have longer service intervals and probably last longer. Whilst it will  be advertised as pure sine wave, unless it has some form of electronic speed control, the frequency is likely to reduce as the load is increased. Some equipment with thyristor control don’t like this. Likewise, at very low loads the frequency can be too high. It is common to have to load the generator with something like a small fan heater to keep some control. This can all be avoided by paying more for a better generator. If you look at the Victron Energy website there is a long report comparing different generators.

We have a Cummins Onan 7 kva Space Saver which has strict control over the output. It is mounted above the swim on the left hand side and is boxed in with sound proofed panels. It has a dedicated fuel tank so no argument about fuel duty, its own skin cooling tank and two silencers in series to keep it quiet from outside ( there was no room for a hospital silencer)

It uses between 1.35 and 1.60 litres/hour and we uses it for about 3 hours a day on average. It is at its most economical when run at about 3/4 of maximum load. We also have a Victron 3000/12/120 Multiplus inverter/charger so the batteries are on charge when the generator is running, provided we have allowed for the power the charge part needs. It will also automatically switch in the boost the available current it we switch to much load on the generator.

The rule is only between 8.00 am and 8.00 pm but if you moor away from other boats and houses then it is not a problem. If you’re mooring near a railway or motorway, the noise of your generator is insignificant.

Having had a dishwasher for 42 of our 45 years of married life there was no way we weren’t having one on the boat. The Indesit we have only uses 7 litres of water for a standard wash, far less than most people use when washing by hand. 

Try to choose appliances that use the least amount of water and have the lowest power use. Apart from the dishwasher, every other appliance we have can be used via the inverter with the engine running if we have to.

‘Joanie M’ was built from the start with a generator but not the one we have now. The original Vetus was mounted on the centre line but proved un-reliable so we replaced it with the Onan mounted to one side. The work was done by Stephen Goldsborough Bosats at Knowle. I would imagine that having it added to an existing boat would mean raw water cooling and a water cooled exhaust. It would also so mean some moving around of the ballast. In our case we couldn’t get to the ballast but did move all the domestic batteries to the opposite side. We achieve a level boat by moving the coal around on the roof and by the amount of wine stored behind the sofa.

Any more questions please ask.

Best Regards

Pete