Generator or Solar?

[Cramelzy]

Can anyone recommend a good generator for our 42' Cruising Cat? We are trying to decide what size and make but also still trying to determine whether we even need one.

We plan on cruising down to and around the South Pacific. We have a 300w solar system and were advised to install a generator, additional batteries and possibly a high output alternator because we also plan to add a 12v water maker and a radar, and want to make sure we have enough power to run the autopilot and nav station at night.

We are still not entirely sure that we need the generator at all. Maybe we can just beef up our Solar and battery storage?

[RainDog]

Originally Posted by Cramelzy

We are still not entirely sure that we need the generator at all. Maybe we can just beef up our Solar and battery storage?

You need to calculate how many amp-hours you will use. You may be able to supply all your needs with solar, or you may not. Depends on how much solar you can fit (300W apparently) plus how many amp hours you will use in a day. I would start here: Systems.

[noelex 77]

Welcome to the forum.

If you can do without a generator it is certainly worth doing so.

Many boats run a watermaker and radar on solar, but usually a bit more than 300w is needed.
You really need to do an energy audit. If you know how much power you are using at the moment (A battery monitor will let you know) it is easy to determine the extra needs of the watermaker and radar.

Solar is cheap at the moment and with a cat there is usually enough room for a reasonably amount of power.

[osirissail]

And an alternative for those in the middle area between clearly needing a genset or not, is a portable inverter-generator like the Honda EU2000i and similar units made by other companies. They normally can output up to 13 amps of 120VAC which is enough for loads like a microwave, toaster oven, or shore power charger.

When the sun don't shine, solar doesn't do much or if you have a wind generator and the wind disappears, having that portable inverter-generator comes in quite handy.

As to watermakers I would seriously suggest only looking at 12VDC (or 24VDC) units primarily so you can run them while enroute out to sea where the water is clear and clean. I have found most cruiser's favorite harbors has seriously dirty water that precludes running the watermaker.

[FlyingCloud1937]

that my friend, you have hit the nail on the head

A lot of peeps, think that it is a water purifier, instead of a water d-salanator.

Lloyd

Originally Posted by osirissail

And an alternative for those in the middle area between clearly needing a genset or not, is a portable inverter-generator like the Honda EU2000i and similar units made by other companies. They normally can output up to 13 amps of 120VAC which is enough for loads like a microwave, toaster oven, or shore power charger.

When the sun don't shine, solar doesn't do much or if you have a wind generator and the wind disappears, having that portable inverter-generator comes in quite handy.

As to watermakers I would seriously suggest only looking at 12VDC (or 24VDC) units primarily so you can run them while enroute out to sea where the water is clear and clean. I have found most cruiser's favorite harbors has seriously dirty water that precludes running the watermaker.

[GordMay]

Greetings and welcome aboard the CF, Cramelzy.

[a64pilot]

If your going to have the Honda anyway, and I think you should as a back-up if nothing else, always have a plan B. Why restrict yourself to 12V watermakers? Can you not run a 110VAC one off of an Invertor for about the same current draw? I know there is some efficiency loss of converting 12V to 110V, but aren't AC motors slightly more efficient off setting some of the loss?

[noelex 77]

There are some high efficiency watermakers that use energy recovery pumps such as Spectra. These use much less power of normal watermaker. They are only available in 12/24v versions (at least for the sort of sizes yachts would use).

I assume the OP is referring to this sort of watermaker, although the power usage is obviously also dependent on the amount of water used.

[u4ea32]

Noelex, I think you nailed it.

If you have the space, add solar. On a cat, you have the room.

Generators suck. If you start down that path, you will soon truly understand. The complexity and problems just layer one on the next.

My boat is fundamentally designed around solar, so no generator for me. Solar is just so cheap, simple, reliable, quiet, light.

Maybe a Honda 2000i, so I can just toss it in the trash when it fails, and buy another at WalMart. But I doubt it, as I have carried those before and never used them.

[senormechanico]

u4ea32 said it best !

Solar is relatively quiet. Think of your anchorage neighbors.
Cats, especially the size of yours have lots of space for solar.
The only maintenance is keeping them clean.
BTW I've got a Spectra, fridge freezer, radar HAM, computer etc, and do nicely with 320 watts of solar. Aerogel helps a lot.

[dandkg]

have you thought about adding more solor and wind generator???we have 500 watts of solor and 400 wind and it powers everything on our boat (they charge 2 8-d agm batteries) just a thought

[Cramelzy]

Thanks to everyone for the input! I think we will definitely add more solar. u4ea32, Noelex, senormechanico, can you please explain more about your solar systems? How many watts, what type of inverter and battery storage are you using?

senormechanico, can you explain more about the aerogel?

As far as using a Honda 2000i for backup, is it ever a problem when the boat is rocking and the generator needs to be on a flat surface?

dandkg, how is the wind generator? I have heard that those can be quite loud as well?

[DumnMad]

I'd go for the high output alternator plus more solar.
Forget the generator and windgen but get LiFePO4 batteries instead so you still have enough voltage for starting even if they run near flat overnight.

[BriaF]

10 yrs live aboard (cat)

4x83watt solar
This supplied 75-80%
Windgen areo 4 gen bit small but very quiet
Added about 10-15%
Generator honda eu10i. 800 watt continuous
charges via 35 amp charger. Makes up shortfall

Running main engines is not cost effective
a honda will reliably do the job at less cost
per hour (used about 10-20%)

Solar will not do it by its self !!!!!!
( unless you have double what you need)
This will allow you to still charge on cloudy
days.

Alternate energy work best when complimentary
Methods used together.
ie. solar wind & water.

I have left my wife aboard for extended periods
& she has no difficulty using the generator.

[senormechanico]

Originally Posted by Cramelzy

Noelex, senormechanico, can you please explain more about your solar systems? How many watts, what type of inverter and battery storage are you using?

senormechanico, can you explain more about the aerogel?

320 watts solar in 3 panels (2 are Aurinco 100w) parallel wired with BlueSky MPPT 2512/IPN Pro Remote
200 aH LiFePo4 cells bulk charged to 13.8 float @ 13.2

Never shore power in 2 years. Never run engine for power except propulsion when no wind.

Fridge/freezer home built with Aerogel insulation. Re insulated hot water tank with it also. Threads on this website about Aerogel.
Heat water with inverter 1000 watt element for 15 minutes a day.
Average hot water temp 110f.
Computer, HAM radio, long distance wifi, diesel furnace, all led lighting.

Above may sound like boasting or BS. It's not.
Aerogel and LiFePo4 changed everything.
It's like being at the dock with shorepower.