How much does that setup cost? And how are you going to charge the batteries? Generator
After you add up the total cost, and then figure how much you will save, how long will it take you to break even?
Say the setup is $2k (I bet it's more). For argument, let's say you already have a few thousands of dollars of solar panels
, so you get the power for free.
A small diesel will burn less than 1gph at 3 kts. So in 2 hours you MIGHT save 2 gallons. We'll even figure $5 per gallon. So, two hours per day that's 400 days. In reality, you'll probably find you do this on average about 1-2 times per week: you'll probably be spending more time at anchor
or in marinas
than you'll be gunking around. So, now it's from 400-2,800 days to break even, depending on how often you will really putz around for 2 hours. That's 1 to 7 years. But wait, there's more.
You don't have those solar panels
? Add a couple-or-three grand for that. Cloudy days? Add another 1-2 grand for a wind generator
. Now we're talking no payback within decades.
Will you have to pay someone to install all this stuff?
Use the generator
? The genset will charge the batteries at it's optimum RPM
range, so you might
save a little there (less the loss of the charging
system). But now we're talking pennies a day saved.
Just charge from the engine
while running? Now you only have that 2 hours of electric running after burning fuel
in the main for several hours. Doesn't help when you are at anchor
Electric has it's uses. In very large applications, diesel-electric can even be cheaper in the long run than diesel alone. Not having to spend several hundred thousand on mechanical transmissions is quite an incentive. The slight fuel savings is just a added bonus.
But for a small boat, IMHO there are very few applications that electric makes sense. For sailboats on the other hand, depending on habits, electric may be just the thing.
Look at the total
cost of your setup. Consider how you will charge. How much time will you be at anchor? Marinas (if you pay for electric, recharge will be cheap
there)? How much are you really saving? How long to payback?
the benefit of quietly cruising in silence. That alone might make it worth it. It's not
a dumb idea. But if saving money
is your goal, I seriously you'll see any.