I’m in a similar place a johnny. I need a reliable supply of 150Ah a day to keep my boat running over an ocean and about a half of that at
anchor. However, sailing mostly in Northern
Europe I am rarely far from a
plug socket. So what I need is a system that will mostly be redundant, except on the few occasions when I temporarily go off piste. A wind generator simply isn’t reliable enough where I sail and it will make a racket in the aft
cabin, and solar panels will either have to located somewhere ineffective (pilothouse roof under the boom) or else on an arch at the back of the boat (which will be an underutilized eyesore on my boat). So having done a lot of sole searching and thinking about my needs, I have narrowed it down to the smallest onboard diesel generator I can get (2kW panduro), or a fuel cell.
Pros of the diesel generator.
1. Uses fuel already shipped aboard and readily available.
2. Can be set up to run automatically when battery charge is low.
3. Will fit in my insulated
engine bay so will be pretty quiet in use.
4. Heats
water for free.
5. Standard, easily repaired
equipment.
6. Long lifespan.
7. Allows for high power
electronics and 230V
electronics (dive compressors, AC units, crash pumps, etc)
8. Fuel is
cheap (about 250euro for a years supply).
Cons of generator
1. Costs about twice the fuel cell to install.
2. Uses dinojuice and thus is ‘’old tech’’ that may even be legislated against in the EU within the next decade or so (of course they might also start producing lots of synth fuel as well so you never know).
3. Requires regular
maintenance.
4. Relatively noisy.
5. Requires a larger battery bank if you don’t want it have to run it daily.
Pros of fuel cell.
1. Easy and
cheap to install (much cheaper to
purchase and install than a generator)
2. Clean in use
3. Minimal
maintenance
4. Silent
5.
Plug and play so in worst case you can just exchange units (you can even carry a spare in case of emergencies)
6. Light weight
7. Can allow for a reduction in battery bank size, thereby further decreasing weight and cost.
Fuel Cell cons.
1. Short lifespan. (Basically, if this is my only source of power and I was
living aboard, then I would chew through its lifespan within a year. More realistically, including
engine and shore
charging, I would need to renew the unit every two years if living aboard)
2. Fuel is only readily available in the North Atlantic.
3. Fuel has to be shipped separately and for full autonomy across the pond and through the
Carribean you will need about 200l of the stuff which means stowing 20 10l jugs.
4. Won’t support high load items (max supply is 8A at 12 V)
5. No hot
water.
6. Fuel is expensive (about 2000 euro for a year’s supply).
Funnily enough, I just this minute had a chat with the yard chief about what would be best and his thoughts were as follows.
1. Outside of
Europe getting fuel for the fuel cell can be problematic at best (and he included North America in this statement) and its down right dangerous to carry serious amounts of methanol aboard to get around this problem. I hand’t thought of that but his point was that in the event of a boat fire, the methanol in those cartridges is deadly. As soon as the fire melts through the first cartridge, if you have more than one or two cartridges aboard, you are dead. The whole boat will go up like a Roman candle. 1 or two cartridges wont make a big difference to the how the fire progresses, 5-10 on the other hand would be lethal and 20-30 you could see from space (my words not his).
2. Diesel generators can be set up to come on automatically to charge the batteries as they get low.
3. Finally, he thinks that he can make the system almost silent in use on my boat. Inside its cover the typical generator is about 50db in volume, but inside my
noise insulated engine bay he reckons that will drop to maybe 40 db and he reckons there is space for it there. I can cope with that level of
noise for 1 hr every 2-4 days.
So I have asked him to quote for the generator
installation. We’ll see then what the damage will be.
The two things that really swung my decision were the fuel availability-dangers of carry methanol dilemma and that niggling voice in the back of my
head telling me that maybe I might want to sail farther afield in the future. Should that day come, I’ll want a generator. Fingers crossed that they commercialize synthdiesel, or I might be
buying into a dying technology here.