Anonymous wrote:

Of course, a main engine or in-built genset will have sound-absorbing material lining their enclosures. A deck box lined with the same material, to enclose the Honda, and to keep rain and spray off it?

 I think a deck box as you describe it,  is a good idea. I have seen examples on YouTube.

Arne is right, it's easy for us not directly involved to come up with more problems than solutions.  The comments about noise were intended to help find a solution that is better for you and those around you.  As a fellow Canadian, I'd like to take the opportunity to say sorry  :-)  For the first year you'll have enough to do already, so what follows below are just ideas to potentially help refine things subsequently should you find the noise problematic.

I wonder if you could also use the deck box to help direct the exhaust over board, maybe like with a propane locker?  Here are some ideas to mull over:

-You'd like to get the heat out of the enclosure, keep the sound in and keep the water out.  I'd put the air outlet at the top of the box, but then send it back down a double-walled side with a series of offset 45 degree baffles that redirect and absorb the sound.  This lets you draw the hottest air from the top of the enclosure, and put the outlet at the bottom where it is easier to direct overboard.  The air inlet would be the opposite, grab outside air at the top and then baffle it to the bottom of the enclosure, maybe with some drain holes to deal with any possible water incursion.  I'm sure there are tons of online resources for building a sound enclosure for a Honda 2000i.  Besides soundproofing and directing the exhaust overboard, such an arrangement might let you run the generator in conditions when it might not otherwise be content, such an enclosure could probably shrug off a wave, and should also reduce the spray the engine would otherwise ingest.

- I just finished installing some 120mm computer cooling fans for our fridge compressor.  Noctua makes some that move lots of air, use virtually no power, but importantly for this application are IP67 dust and waterproof.

-The Honda has a 12V DC output that could be used to run a fan or fans independent of the AC.  However, this output is unregulated and electrically noisy, so the electronic computer fan above might not like that.  Two solutions are, use a simple DC motor like a bilge fan (uses more power, but still within the limits of the 2000i DC system), or use a DC-DC converter to feed clean power to the computer fan. I haven't used this particular DC converter, but have used similar ones in the past to get clean 12V power from an outboard motor.

-line the box with the same soundproofing used for inboard engine compartments (foam, with a vinyl mass dampening layer and a shiny mylar outside).

Quiet Nova Scotia anchorages sound lovely.  In summer, the same cannot be said here in BC from Desolation Sound south.  Perhaps that's why the sound of a generator gives me an involuntary twitch.  Bonne chance mon ami.

Anonymous wrote:

Running in the daytime would help. It's awful on a beautiful peaceful morning or evening when people run them, especially on deck. Plywood deflection sounds interesting (no pun intended). Generator noise really carries for people on shore too… Is there much current – river or tidal – where you spend your time? There are some interesting water turbines these days.

Shemaya

No, there isn't much current where I spend time.

I came across an item on YouTube where an owner had leaned 4 pieces of plywood against his generator (with corners open) deflecting the sound into the soil. That wouldn't work for us. What if they were pointing upward, corners closed, like a funnel, deflecting sound straight up? I suspect that won't work, the sound "boiling over" so to speak. It would be easy to try if I had a generator. Going a step further with this concept, what about a folding parabolic dish (like a handheld fan) with the generator at the center, pointing upward? Space providing. 

Running in the daytime would help. It's awful on a beautiful peaceful morning or evening when people run them, especially on deck. Plywood deflection sounds interesting (no pun intended). Generator noise really carries for people on shore too… Is there much current – river or tidal – where you spend your time? There are some interesting water turbines these days.

Shemaya

Jan wrote:

Well the most recent turbine I had, which burnt out at the end of January in Storm Brendan, would have contributed approxiamately zero amp-hours to the batteries overnight in such a scenario. Any anchorage worth anchoring in will hopefully not be blowing a steady force 6 or 7 which is needed for these little gennies to crank any useful power out. In fact, and it's a current best-selling model, it's controller actually uses more power than the turbine creates for most of the time. 

You do see them quite often on cruising boats but one wonders if the owners are delighted with them, most I've talked to are not. 

I have had experience with two wind generators on our previous yacht 'Footprints'. The first was a Chinese copy of an earlier Rutland 5 blade wind generator, the big magnet in the hub type. We had that for several years including our offshore trip to New Caledonia. I was very happy with the unit, especially considering it's landed cost of $350 into New Zealand. It supplemented our solar panels and even during nighttime when ocean crossing our batteries were generally up over 13 volts. That wind generator was destroyed in a mooring incident and the insurance company replaced it with a genuine Rutland 6 blade unit which I always felt never had the output of the Chinese copy. Regardless it did boost our batteries when there was wind, and the genuine Rutland was very quiet, whereas the Chinese unit created enough wind to act as a handy wind speed indicator. When off watch at night if I heard the wind generator screaming I knew it was time to put a reef in, if I could not hear the wind generator I knew we probably needed more sail! 

Expensive yachts with in-built gensets have some very effective exhaust systems these days, with gas/water separation. Even so, the humming sound, even at low volume, is annoying to those close by, and I, for one, heave a sigh of relief when they turn them off. I cannot believe that a portable air-cooled genset can be anywhere near as quiet.