Replace Generator or switch to 100% solar/wind?

[makoman]

You need to seriously consider the effect on resale value of the boat. Without a generator, far fewer buyers are going to be interested in your boat, which, according to my Econ 101 prof, means a lower price.


I found this out the hard way years ago when I tried selling my 41 Ft. Cheer Men trawler with only an inverter and 10 battery bank. Had to install a generator in the boat in order to sell it.

[FlyingScot]

I have the same boat. Yanked the broken factory installed NL 6kw (water damage from trying to start too long with water lift exhaust, not me).
Installed 1440wp solar and 900ah FF oasis. Still need Honda 2.2kw to run one factory installed 16k btu aircon. Starts 9/10 times in Eco mode. Still wish I had a small unit to cool just the sleeping cabin to run from batteries. Of course you have to make up the power sometime, but I rather run my Honda during the day for numerous reasons.

If you really need a lot of aircon, you need a generator. You can't fit enough solar and still have a sailboat when you're done on this size Cat.
Also the boat isn't insulated. The aircon compressor basically runs continuously, until it gets too cold then it shuts off and heats back up amazingly quick. A variable speed unit would help in this regard. I haven't found a perfect solution. Do I add a third small unit? Replace one of the two 16k units? Replace both of the 16k? Decisions that take time/money with no guarantee of happiness.
We make between 4-8kwh per day with a typical output of 6kwh. It goes quick when you have multiple fridges/freezer and want to make/heat water.
I wish I had double the solar.

[ausnp84]

Just back to the OP’s initial post, if you’re going to replace the wind gens I’d avoid Rutland and go with something else. I’ve personally had two 914s fail (electronic issues) and know three other people who’ve had similar problems....

N

[SunPoweredYachts]

I often quote some feedback we had from a customer with a Nordhavn 63 that added solar panels, "you can't underestimate the importance of running a quiet boat".

[cndcruiser]

If you upgrade the 2 standard alternators to something like Balmar XT170 with external regulators, set up to derate to say 70%, you'll get 2x 110A to quick charge the batteries. Maybe upgrade 100W wind gens to 350W (SuperWind 350 or D400). Fix the generator and address the moisture issue. A good enosure with air supply from dry location?

[sv Stella Maris]

Cat-Keys,

Good day if you're still reading this far down. I'm assisting a new family on a Lagoon 420 to get started. At the same time they upgraded all electrical.

(3) 930w panels + (4) 420w panels off the back

(3) Victron MPPT's

(4) Relion 300ah @ 12v lithium

Relion is expensive, but a solid company if you aren't comfortable assembling your own cells direct from manufacturer.

The cost for a 'genset replacement bank' is priced at or just below a genset. But required almost no maintenance and is silent.

I myself have 2.3kw solar and 800ah @ 12v AGM's. I do everything for my family of 8 without a diesel genset. I can't run aircon overnight with these batteries, but we don't have air con, so it doesn't matter, hehe. We do have a 2kw portable genset for safety; I've used it 6 times this year to make water when the sun didn't agree.

We make 130l/hr off solar and charge our batteries everyday by noon.

Go solar, go big. But go light on the aluminum frame. Rigid panels are self supporting. Off the Starboard Hull YouTube couple has the array design I build...works great.

420w panels available from AltE Energy, ask for Blanca, can be freight forwarder worldwide.

I dont touch wind with my kids aboard...to dangerous for climbing monkeys ! Ha ! ...and noisy...

PM for any more details. Good day.

[witzgall]

Check out these little baby A/C units from Climma.
https://www.coastalclimatecontrol.co...ditioning.html

35 amps @12v from batteries/inverter, including the pump.

Good for cooling a sleeping cabin only, but tiny, too, making installation at the location easier. Use a very short duct run - straight and direct if possible. Many people don't realize how much inefficiency is introduced by long or complex ducting runs. My wife and I lived three summers in Annapolis on a 44ft center cockpit ketch with ONE 12k unit in the salon. It had a straight six inch duct. Yes, it was louder, and the sleeping cabin in the rear could get a bit stuffy, but it made it bearable. Doing the same thing in a sleeping cabin with a small unit should work well.

Chris

[Rob_P]

There's something I don't get.

Semi trucks hauling produce or meat across the country use trailers that are cooled by a diesel powered refrigeration unit. Basically, that 40 foot trailer is a giant refrigerator and it's kept at a constant temp of around 40 degrees even in the summer in the US desert southwest.

Think about that, they use diesel powered refrigeration units and those trailers have more volume inside than most boats do. And no one is going to do that if it's more expensive than any other method.

So why are we trying to convert fossil fuel to electricity to run an electrical powered A/C unit with all of the energy losses involved in that? From my viewpoint, wouldn't it be better to swap out the powerhead on the genset for a refrigeration pump setup and run the A/C directly off the genset engine that way? The mounts and stuff would probably would have to be custom made but since when did that stop anyone?

Mount an automotive A/C pump to the genset engine and run vibration isolated freon lines to where you want to permanently mount the rest of the A/C unit. Everything you need you can get from your current A/C unit except the automotive engine pump. You'll get dedicated A/C without any worries. You'll still need some electricity to power the A/C fans inside the cooling unit, and you might have to put a small fan in the genset locker to keep that all cool, but the main workhorse will be diesel powered.

The engineering is the hard work but someone out there ought to be able to figure this out. I just find it hard to believe no one has done it yet.

[john manning]

I got rid of my genset (6KW) six years ago and have tried to run off solar and inverter since. It works but compromises have been made.

I do not use my hot water cylinder unless on shore power (1KW). My maximum AC current draw is about 2Amp unless running the engines where I go up to 5 Amp. That is 1.2KW. The limit I found was related to current drawn from the batteries. At 1KW on the inverter I am drawing about 95Amps off the batteries. That needs large cables to prevent overheating. But I cannot change the size of the connectors on the inverters and they start to heat up if I go over 100Amp. (2.5KW Mastervolt inverter).

I am now looking at ways to reinstall a genset because I want my hot water back.

[smj]

Originally Posted by john manning

I got rid of my genset (6KW) six years ago and have tried to run off solar and inverter since. It works but compromises have been made.



I do not use my hot water cylinder unless on shore power (1KW). My maximum AC current draw is about 2Amp unless running the engines where I go up to 5 Amp. That is 1.2KW. The limit I found was related to current drawn from the batteries. At 1KW on the inverter I am drawing about 95Amps off the batteries. That needs large cables to prevent overheating. But I cannot change the size of the connectors on the inverters and they start to heat up if I go over 100Amp. (2.5KW Mastervolt inverter).



I am now looking at ways to reinstall a genset because I want my hot water back.

What kind of boat do you have? If you have a diesel/diesels you can run your water heater of the cooling water side. If you have an outboard you can run your water heater of a Honda 2000 generator or install an on demand propane water heater.

[Simi 60]

Originally Posted by smj

What kind of boat do you have? If you have a diesel/diesels you can run your water heater of the cooling water side.

Assuming you run your main engines for a length of time daily.
We don't, often a week between starts

If you have an outboard you can run your water heater of a Honda 2000 generator or install an on demand propane water heater.

Or you can get the genset head unit repaired or replaced.

[Alistair242]

Originally Posted by makoman

You need to seriously consider the effect on resale value of the boat. Without a generator, far fewer buyers are going to be interested in your boat, which, according to my Econ 101 prof, means a lower price.


I found this out the hard way years ago when I tried selling my 41 Ft. Cheer Men trawler with only an inverter and 10 battery bank. Had to install a generator in the boat in order to sell it.

“Years ago” . I believe the idea now is to go away from fossil fuels, or at least to minimise the need to use them, in the same way that we all need to minimise or stop completely from utilising single use plastics. That is the future and there is no way around it.
If you must have air conditioning most of the time there are small 12v and 110-220v ACs that can be run from batteries/inverters at least some of the time. Solar and battery technology continues to become more efficient and affordable. Maybe we are not quite there yet but it certainly is feasible, even a deal breaker for us, to be genset free. Electric main engines are becoming a practical choice for some and will become more so as well.
Quite a few boat buyers now will not consider a boat that relies on a generator, us included. Investing in upgraded solar, battery and renewable energy systems may be money better spent than replacing a generator?

[john manning]

Originally Posted by smj

What kind of boat do you have? If you have a diesel/diesels you can run your water heater of the cooling water side. If you have an outboard you can run your water heater of a Honda 2000 generator or install an on demand propane water heater.

Thanks but those paths are not simple. Its a Prout Escale catamaran. Engine heating would require a new hot water cylinder and relocating the cylinder and plumbing and then running the engine hoses through a bulkhead. Califont heaters waste too much water. Small portable gensets have been tried but I did not like the noise.

My current plan is to run a 230V alternator off one engine. I am designing a system that limits the side loading on the drive pulley.

[cat-keys]

Originally Posted by witzgall

Check out these little baby A/C units from Climma.
https://www.coastalclimatecontrol.co...ditioning.html

35 amps @12v from batteries/inverter, including the pump.

Good for cooling a sleeping cabin only, but tiny, too, making installation at the location easier. Use a very short duct run - straight and direct if possible. Many people don't realize how much inefficiency is introduced by long or complex ducting runs. My wife and I lived three summers in Annapolis on a 44ft center cockpit ketch with ONE 12k unit in the salon. It had a straight six inch duct. Yes, it was louder, and the sleeping cabin in the rear could get a bit stuffy, but it made it bearable. Doing the same thing in a sleeping cabin with a small unit should work well.

Chris

Thanks Chris - that's a great idea. exactly what I was looking for. Also checked out Termodinamica at termodinamicausa.com but their 16,000btu units seemed overly expensive even if they only use half the energy



We have an owner's version Leopard 40 and the master berth can easily be cooled even on the hottest night in Florida by 4200BTU's I think. We have a 2000w Xantrex inverter, so I think the best compromise is:


1. install clima compact 4200btu unit $1400 plus installation cost (maybe I can do this myself) supplemental to the cruise air 16000btus that we can still use if in a marina


2. upgrade batteries to LiFEPO4 like relion maybe double the capacity I have now to 1200 Ah - maybe add a soft start



3. upgrade solar from 5 x 85w to = 425 to perhaps 6 x 175w 1050w


if we have guests during super hot summer months they will have to do what my wife and I have been doing for 2 months..GET USED TO IT! we have a wind sock and fans that make it bearable - and its really only 3-4 months out of the year - so with Lithium at least we dont have to worry about cycle life like we do now with the Lifeline AGM's



I really like the idea of noise free anchoring - the generator just kills that peacefulness especially when its totally calm.

[FlyingScot]

Originally Posted by cat-keys

We have an owner's version Leopard 40 and the master berth can easily be cooled even on the hottest night in Florida by 4200BTU's I think. We have a 2000w Xantrex inverter, so I think the best compromise is:


1. install clima compact 4200btu unit $1400 plus installation cost (maybe I can do this myself) supplemental to the cruise air 16000btus that we can still use if in a marina

...

I really like the idea of noise free anchoring - the generator just kills that peacefulness especially when its totally calm.

If it's the factory installed Xantrex combo shore power charger/2kw inverter, then the unit is modified sine wave. Unlikely to run an AC. If it does run I would expect a short life.

I'm investigating cooling just the owner's cabin with a small third unit. AC is cheaper but would require another dedicated inverter, or replace the main one.

The DC units seem tempting except the price. The wiring would be very short as the owner's cabin is right next to the battery bus bars.
SV Cosmos