Gas vs Diesel generators.. Help? (Little Hondas vs Fisher Panda Style)

[CaptainShack]

So I've been pricing out generators for our boat.

The mission here is to...

Provide extra power when we want to run the electric drives for extended periods of time, pushing how long the batteries last when sailing isn't an option. ICW-work, heading through Okeechobee again.. ect.

I've got an older prout 33. She sails fine and is super sea-kindly. The section that was my engine bay. A fairly large box set aft of the boat, before the deck will now be empty. Its got 2 large bay doors one facing forward of the box, and one facing aft, already setup for exhaust out the rear of the boat between the hulls. "from the old engine setup"

I'm trying to understand the benefits of Diesel vs Gas and the general differences between say honda's new 3200i - at 59 pounds. Costing only 2,600$ vs say a fisher panda 6500 last quote 13k$ at 350lbs

The engine bay is clean and dry. Sealed, vented as 2 of its walls are literal doors with a 2 foot span. I must be missing something as you could have twin honda's running with there parallel connect options and popping the doors open, to start producing 6kw+ for half the price of a Fisher Pandas. Potentially more reliable?

Feel like I'm missing a step. Is exhaust the problem? Or do honda's disintegrate on a boat rapidly? Noise issue?

Thanks for shedding some light on this!

[rslifkin]

The small air cooled gas generator will be dramatically less efficient than an installed diesel unit. I did an analysis on this a while ago, which can be found here: https://www.cruisersforum.com/forums...ml#post3079298

[Emmalina]

The Honda is air cooled so needs to be outside ! and runs on gas. The Fischer panda is water cooled and runs on diesel so should last longer and no gas onboard for fire risks. Not a big fan of FP fixed a good few over the years but there are other options.

[CaptainShack]

Interesting.

So one of the pros for a diesel unit over gas is better efficiency per gal.
Another pro mentioned in that post you linked I didn't even think about was most boats already run diesel so tapping into that larger fuel supply must be nice.

[rslifkin]

Another big thing is that air cooled portable units are significantly harder to make quiet. Even the "quiet" ones are still pretty loud compared to a well muffled water cooled generator (especially if it's in a sound enclosure).

[Searles]

Be carefull of getting petrol exhaust fumes into your cabins and sleeping areas ,they will kill you verry silently and quickly.⚓️⛵️��

[Drunkonwatch]

It will take 6 to 15 sets of Honda’s to equal the lifespan of the northern lights on a boat.

[sailorboy1]

I have a small inboard diesel generator, but got a Honda EU2200 for running smaller loads. Shortly after that the diesel generator broke AGAIN. By that time I was already liking the Honda better so didn't repair the diesel that had already broke down 4 times in 2 years. Yes the Honda wouldn't runa run as many things at once, but is quieter and uses the same or less fuel as the diesel. It has been 4 years and the Honda now has twice the hours of the inboard diesel and the only things have been replacing the pull cord and cleaning the carburetor a couple times. The cost of that is about $10.

The next maintenance I do to the diesel generator is to remove it.

[SailingHarmonie]

We recently swapped out a 26 year old Onan 6.5kW diesel generator with almost 9000 hours on it.

The only reason we removed it was we could no longer get spare parts for the electrical side of it and the marinization parts. We need a reliable generator, and not being able to gets parts was a killer.

I am very doubtful there are any Hondas that have done two circumnavigations, and run for an average of one hour a day for two and a half decades.

As has already been made clear, you can not install a portable air cooled gasoline generator in a closed engine bay. Well, I guess you CAN, but you can not do it safely.

Long and short of it, is a portable generator would be a cobbled together arrangement for what you want to do, both mechanically and electrically. A "proper" diesel generator is a reliable tool that can be installed in a safe way with a good electrical connection that would be safe and reliable.

Realize also, you (likely) do not need an AC generator. You can find units from WhisperPower, FP, and Polar Power (among others) that generate DC power more efficiently than you make DC from an AC generator. They might be the better solution for you. Smaller, lighter, more efficient, cooler running, they have a lot to recommend them for people who do not need ready access to high amperage AC power. What you are looking for is a market they are selling into, for good reason.

[Madehn]

it may be a personal prejudice, but the fewer things i have to store explosive fuel for, the better. That being said, i have not heard many bad things concerning the small honda EU2000 units or their latest iteration of these. They are noisier but are reputed to be sturdy and dependable. if you have everything already plumbed for exhaust and cooling water, i would tend to go with a small diesel generator from one of the known manufacturers like westerbeke, northern lights, etc. i have heard very little good about PANDA. one considration is that the diesel setup will be much heavier than two small light gasoline generators. For the money of a decent used diesel unit, you can probably pick up two EU22200 units and have enough left over for a spare set or at least one spare unit. Balance that against the noise and storing the much more explosive fuel. good luck

[Lepke]

Pros and cons are the same as the main engine. I've never heard of a Honda or copy going thousands of hours.

[mvweebles]

Originally Posted by Lepke

Pros and cons are the same as the main engine. I've never heard of a Honda or copy going thousands of hours.

Never heard of a Fisher Panda going thousands of hours either.......

OP - if you decide in diesel inboard, and want a smaller, lighter footprint, consider the NextGen brand. Not as robust as Northern Lights, but significantly better than FP.

[Buoyant Cruiser]

We keep a Honda EU2200i on the boat mostly for AC / Heat when on the hook. A Smart Start unit on the HVAC was needed to reduce start up power surge. The 3200 mention has similarities to the 2200. Our experience is: the plus is we already owned the generator. The disadvantages are:
1: The generator is air cool and designed to operate
outside in open air.
2. Honda’s make less noise than others, but under load
they run at a fast speed. Since air cooled it’s noisy
enough to disturb others nearby.
3. Under load the run time is 3 to 4 hours before
refueling. So plan on getting up in the middle of the
night to refuel.
4. Gasoline not as safe as diesel.
Recommend spend the money for a water cooled diesel set that comes in an acoustical box.

[SailingHarmonie]

Originally Posted by Buoyant Cruiser

2. Honda’s make less noise than others, but under load
they run at a fast speed. Since air cooled it’s noisy
enough to disturb others nearby.

Kudos to BuoyantCruiser. It is a VERY rare Honda generator user on this forum who will admit that anybody else can even hear their buzzing machines, much less be disturbed by them.

We have been full time cruisers for 7 years. Never--not once--have we run our generator at anchor to run AC. We just open hatches and let the fans and the breeze do their thing. Because we sleep with hatches open, these little lawnmower engines running all night drive us nuts. It's doubly frustrating because if we are running our generator, nobody else knows.

Nothing gets us out of an anchorage faster than a boat that starts a little gas generator and then everybody on board goes below to bed. Of course, come to think of it, for them, that might be a plus...

[Jammer]

Fisher Panda and portable Hondas are both low buck cost saving solutions to the problem.


Non-marinized gasoline generators are not ignition protected. If below decks they are a non-starter for ABYC compliance and therefore for passing a survey and getting insurance. They have no provisions for routing exhaust overboard and are air cooled as noted upthread. Lifetime fuel and maintenance costs are higher than water-cooled diesels. Useful life is shorter particularly under heavy load.


Among diesel generators F-P is the most inexpensive, Next-gen is somewhere in between, and Northern lights would be the most expensive but quietest and, on the average, longest lasting with the least maintenance. Scheduled maintenance on the Northern lights is once every 200 hours, it's every 100 hours on the others.


Generators are an expensive way to make power. You're looking at over $1 a kwh all up with any of them.