I have been looking into this in detail on my current
boat and it totally depends upon how you intend to use the boat.
Unless you are going to live aboard full-time with lots of power-hungry devices, or intend on going diesel electric
in the near future, a built in diesel
generator is not worth the money
. Bare in mind that in Europe
and similar places they are literally banning the sale
of new ICE personal vehicles from 2025-35 depending on country. This severely bites into the payback potential on any investment in new diesel onboard in Europe
Portable gasoline generators are noisy, difficult to use underway, a PITA to store, and require active management. They might be worth it as a budget
solution for a limited duration sabbatical trip, but only if you love the noise
of gasoline engines.
The new 150i EFOY can deliver 1.8kWh a day, if running 24/7 which is more than most sailors need. But if you do that then you will eat through the units working life expectancy at the rate of 1% every 2 days! As they cost 5000+ euros to start with it is an expensive solution even for a sabbatical trip (I worked out that the unit would be nearly dead after my planed sabbatical atlantic circuit), and totally outrageous for a live aboard.
Solar is great and works well on catamarans, but is difficult to do well on monohulls without adding an arch at the back of your boat. Doing that significantly adds to the cost of doing solar. I looked into it and in Sweden
the cost of getting an arch made and fitted was going to make the diesel generator look cheap
in comparison (10-15000 euros). Even doing something off the peg and cheap
like sun bar
was going to be around 4-5000 euro fitted. That might be worth the investment if your home berth has no shore power
, or if you are living aboard
and don't mind the extra windage and aesthetic hit, but for a sabbatical cruise
or normal holiday cruising its simply not worth it IMHO. Add to this that present cell tech is going to be obsolete in about 5 years once multilayered cells hit the market (toward 50% efficiency) and it makes investing in substantial solar questionable for all except those who really are heading off into the blue for a very long time in the very near future.
I also looking into hydropower but there one has the problem that you only sail 5-10% of the time you are aboard when living aboard
and the things tend to have all sorts of issues with weed and deployment, particularly in the sarragosa sea, which is where I will be sailing.
generators also have limitations. They require care in handling and maintenance and they produce surprising little power. I need about 1,5kWh a day when sailing and about half that when just sitting. To keep me charged a wind generator
needs to supply 60W on average which the silent wind
12V unit requires 14kns apparent to do. For western Europe and Caribbean
cruising, and with a sufficiently large battery bank to buffer for the occasional lull, this is just about workable, but if you are in climes without something like the gulf stream
winds then you are going to be disappointed with a wind generator.
So again, it all depends on where you are and what you are doing.
If I were going to travel all over the world with a traditional diesel auxiliary monohull
without too many toys, then I would fit an arch and put lots of solar on it and perhaps also a wind generator. I would do the same on a catamaran
though now you can also have lots of toys.
If I were living aboard with lots of toys on a monohull
or going diesel electric on propulsion
and the galley
, then I would fit a diesel generator and maybe a few panels
If I were cruising for a fixed period of time (say a year), then it would be toss up between fitting pole mounted wind and solar, or a fuel cell. Which would depend on multiple factors but mainly on what you will need once you return. If you just going to use the boat for normal holiday cruising and the odd weekend after the big trip and have shore power
at your home mooring
and in the environs, then a fuel cell is probably the easiest thing to live with albeit at about twice the price of the wind generator and panels
over the years. Over the sabbatical you will have run through much of the cell's working life, but enough will be left in it to give you some boosts on the rare occasions where you haven't been able to charge your batteries
by shore power or engine and it won't be cluttering the lines of your dock
queen, or bothering the neighbours. If you ever decide to up and go again for another sabbatical, you just replace the unit. If, on the other hand, you don't have ready access to shore power where you cruise
or at the home mooring
, then the wind and solar option on a pole is a better bet on a cost benefit analysis. Both systems will get the average cruiser around the pond so long as you are reasonable in what you ask of them, but they meet different needs once you return.
If you are just holiday cruising with the occasional weekend tossed in over the year and have shore power on the home mooring and in the environs, then you don't really need anything over and above a good battery bank and reasonable alternator
on the engine. A 300Ah lithium bank will last you a good few days between charges, and you will recharge at around 60-120A per hour off the engine, or better off shore power.
If you are just holiday cruising with the occasional weekend tossed in over the year and you don't have shore power on the home mooring, and in a region where there isn't much shore power available, then you will need some combination of wind and solar to keep your batteries
charged, but you won't need much.
Under no circumstances would I ever do a portable petrol generator. There are just better options out there.
That's my two cents