Power

[Danthegorrila]

Power generation?

We're off next year and are fitting out at the moment.

Much of the advice is to keep it simple and avoid stand alone generators (AC or DC), but when we spoke to our local installer his advice was to get a generator! (DC).

We already have an areogen 6 and a 75w solar pannel we estimate needing 150-165 amps per day. The engine is 36hp and the local electrical guy thinks this would not drive another 100-150 apm geni and would be expensive in fuel.

What advice do you all have??


PB

 

[rex]

I don't believe the engine would not drive a bigger alternator, it may be tricky to fit but that is another matter. I would suggest leaving the existing alternator set up as is and fitting a big second alternator. This would need a twin belt drive and I would suggest a large diameter crankshaft pulley so you get full output at low revs. Fit an Adverc or similar regulator as well, it will really bump up the charge rate. Don't try and fit a large alternator in place of your existing one, the belt will not be adequate and you will loose the benefit of two altenators in case one goes down. I am not sure a standalone DC generator (alternator?) would be worthwhile considering the room and installation costs.

 

[ean_p]

think you need to think hard about what you want the additional output for.....if it 's to charge batteries then leave it to your existing setup....if its to charge batteries should you have problems starting your engine or otherwise then get a genny...or if its just to supply dc power without having to use your engine then go whisper genny...all in all if you can afford the unit and the space then a stand alone has got to be better ...but think about what you want it for ....and why dc why not 240 ac which in most modes is cheaper and provides more flexibility even to feed your charger for the batts and your inverter for the goodies.....but you need to decide what you want to achieve....

 

[dk]

Don't go AWOL with the alternator, just make sure you fit a smart regulator to make the best of what you already have. Try it first before you go to all the trouble of fitting a second alternator. Your existing one is probably capable of outputting some 40A+, which with your alternative energy resources would probably mean only running your engine for a couple of hours a day. If it isn't enough, a 100A alternator would be plenty and should fit as a direct replacement, albeit with a different length belt.

 

[summerwind]

Whilst I can sympathise with the view that another alternator fitted to the engine might be economic, I can't avoid the feeling that a stand alone 240v gennie is a better alternative.

The advantages I see are that a small gennie can be started by hand. Can you start your main engine by hand?

The gennie is flexible and 240v can be used for many things other than charging accidently flattened batteries and without waiting for the solar panels / wind gennie to do the job.

A wide range of appliances (That you probably already own) can be used with the gennie without the strain that an inverter will put on your battery bank.

Good luck with the fittin out. My experience is that it is a far bigger job than you expect.

 

[rex]

Don't try and drive a 100A alternator and smart regulator with your existing belt, especially if it drives your water pump. You will get a smell of burning rubber, no charge and no engine cooling if it shreds. Honest. By the way I found Adverc very helpful even though I wasn't buying anything from them.

 

[Guest]

I have had a small Yamaha 800 generator for the last 15 years - and it's still going strong. OK, I also have shore power, plus 3 x 120 amp batteries. On my new boat I am going with shorepower,3 x 75 amp batteries solar panels x 2, inverter, battery management etc. But for all that, I am taking my trustworthy genny! It's about the size of a suitcase and will just run the odd power tool - but it charges the batteries beautifully, and is very quiet - nearby boats say they cannot hear it. and it runs on a pint of unleaded petrol. It sits under the cabin table out of the way - so I don't find it a inconvenience. It does mean that anywhere, any time I can charge the batteries.