Back up generator

[cla6665]

Hi all,
trying to decide on a back up generator. We are going to be running most of our equipment with solar panels and a wind generator. What would be a good size generator for back up? There are many portable generators available, from 1000 watts up to many thousands. What would be a good size to have on board when solar and wind are not enough.
Thank you very much

[skipmac]

Part of the decision process would be based on the size of your battery charger. Lots of previous discussions. Consensus is the Honda EU1000 or EU2000.

[DeborahLee]

The EU2000. much more useful. You can run a micro wave or coffee pot or my favorite a ceramic space heater. Most of these need 1500 watts.

[jeremiason]

You need to be more specific about your power requirements... What do you want to run on the generator? If it is only a battery charger, than the obvious answer is the size of the generator would have to match the power requirement of the charger.


We used a Honda 2kw portable generator on our last boat, a Catalina 36. It ran the battery charger and the hot water heater just fine.... On our present boat, the Honda 2kw wouldn't put a dent in our power needs, but a Honda 2kw has the ability to run in parallel with another 2kw generator, if you need that much power.

The Honda 2kw uses very little fuel, depending on the load, is relatively small and has a small internal gas tank. On the other hand finding parts outside the USA could be difficult.

All in all for less than a $1k it is a good unit.

[Pete the Cat]

Originally Posted by DeborahLee

The EU2000. much more useful. You can run a micro wave or coffee pot or my favorite a ceramic space heater. Most of these need 1500 watts.

Yes, It weighs nearly twice as much, makes almost twice as much noise, takes up more space, uses more fuel, costs more---think about your needs. A 1000 watt generator will power a 40 amp/hr shore charger which is more than most battery banks can take. If you want to run an air conditioner, and electric heat devices, you might think about just getting a trawler and go for a 10+KW that you run all the time. Just do it somewhere else. You would probably be more comfortable as a power boater or stay in your condo. And please do not anchor near me.

[SailFastTri]

Originally Posted by Pete the Cat

Yes, It weighs nearly twice as much, makes almost twice as much noise, takes up more space, uses more fuel, costs more---think about your needs. A 1000 watt generator will power a 40 amp/hr shore charger which is more than most battery banks can take. If you want to run an air conditioner, and electric heat devices, you might think about just getting a trawler and go for a 10+KW that you run all the time. Just do it somewhere else. You would probably be more comfortable as a power boater or stay in your condo. And please do not anchor near me.

Actually the EU2000 (or Yamaha ef2000is, my choice) runs quieter at less than full load, and because it is less likely to be run at full load it is more likely to throttle down in "eco mode". So in actual use it is more likely to be quieter. Even at full load, the difference is hardly "twice as much noise". As for the size and weight, anyone an read the specs and see you're wrong.

[casual]

I,bought a Denard 3500 sienuwave Gen for a cold trip home in Jan from Md to run cabin heaters Ran 2 900 watt ceramic heaters no problem 700.00 bucks for the gen E bay.

[Cotemar]

Honda 2000 in "eco mode" is just pure joy. It can be at your feet and still have a normal conversation. If you put enough solar panels you will never have to use it.
Since we put 460 watts of SunPower panels on 3 years ago we stopped taking the Honda 2000.

[Pete the Cat]

Originally Posted by SailFastTri

Actually the EU2000 (or Yamaha ef2000is, my choice) runs quieter at less than full load, and because it is less likely to be run at full load it is more likely to throttle down in "eco mode". So in actual use it is more likely to be quieter. Even at full load, the difference is hardly "twice as much noise". As for the size and weight, anyone an read the specs and see you're wrong.

I agree, read the specs on the generators and your charging needs. Given the charging process of most smart chargers, the "eco" mode will come on on both chargers and battery systems within approximately the same period because banks cannot take full charge loads just because it is available.. Think before you go "more is better" road. Many "Equipment Kings" out there in the cruising world who have the "mine is bigger" orientation to amps and power. Think about why you went cruising in the first place before you become one of them. Anyone who can read the specs can make a decision based on facts and their own situation.

[jeremiason]

Originally Posted by Pete the Cat

Yes, It weighs nearly twice as much, makes almost twice as much noise, takes up more space, uses more fuel, costs more---think about your needs. A 1000 watt generator will power a 40 amp/hr shore charger which is more than most battery banks can take. If you want to run an air conditioner, and electric heat devices, you might think about just getting a trawler and go for a 10+KW that you run all the time. Just do it somewhere else. You would probably be more comfortable as a power boater or stay in your condo. And please do not anchor near me.

Why so hostle.... Not everyone lives like the Pardee Family. Sailing doesn't mean you have to give up comforts just to prove your salty.


My analogy is that some people camp in tents, while others use 40 foot RV's... They are all still visiting the forrests...



Your comment that a 40 amp battery charger is more than most battery banks can take is only true if you are sailing a boat that hasn't upgraded the house bank from two group 27 bateries, which now a days ins't the case with most sailboats. Almost every cruiser I have met has upgraded their house battery banks. Also most newer boats come with large house banks of 300-400 ah or more to begin with.


Our boat came from the factory with 675 ah battery bank, which I later upgraded to 968ah before we started fulltime cruising. Your 40 amp charger would be inefficeint on this boat taking 15 or more hours to fully charge the house bank.


We have two refrigerator/freezers, which use about 150 ah per day in the tropics. Our solar (795 watts) keeps up with everything as long a there is sun, but the batteries go down fast when the sun goes away.


Also on your comment about big gen sets...


Although I don't run it much, my sailboat's air conditioning has been a plessing on hot nights in places like Summer in the Sea of Cortez and the jungles of Costa Rica. Not to mention it dehumidifies the boat and helps prevent mold.


As far as your concern about large generators... I am with you, I don't like loud gen sets and irresponsible owners who run them at all hours.

We have Fisher-Panda Mini 8kw with an Aqua Lift Muffler... The only thing you hear outside the hull is running water from the exhaust... It is the quietest Gen Set I have seen (or heard).


OK sorry to get off on a tangent, but all of us live differently on sailboats...
...

[skipmac]

Originally Posted by Pete the Cat

Yes, It weighs nearly twice as much, makes almost twice as much noise, takes up more space, uses more fuel, costs more---think about your needs. A 1000 watt generator will power a 40 amp/hr shore charger which is more than most battery banks can take. If you want to run an air conditioner, and electric heat devices, you might think about just getting a trawler and go for a 10+KW that you run all the time. Just do it somewhere else. You would probably be more comfortable as a power boater or stay in your condo. And please do not anchor near me.

Gee, didn't see the original poster say anything about air conditioning or electric heat and they did say they were supplying their power requirements with solar and wind, looking for a backup gen for a sailboat.

I love peace and quiet as much as anyone and have anchored close to boats, even trawlers, with large gensets and usually (no not always) heard nothing louder than the water splashing from the cooling pump.

[Dockhead]

Originally Posted by skipmac

Gee, didn't see the original poster say anything about air conditioning or electric heat and they did say they were supplying their power requirements with solar and wind, looking for a backup gen for a sailboat.

I love peace and quiet as much as anyone and have anchored close to boats, even trawlers, with large gensets and usually (no not always) heard nothing louder than the water splashing from the cooling pump.

This is really getting off topic, but the splashing water can be eliminated with a water separator and below waterline cooling water discharge. My 6.5kW Kohler is inaudible to other boats. I can't even hear it myself inside my own boat if the Espar heat is running.

[Pete the Cat]

Just to stay on topic for any one who is interested in sizing a generator. I carried a 1000w generator for two years cruising Central America. I have 440 ah of golf cart batteries and the generator was all you could ask for that system. If you have and need 975 ah of batteries you could use a 100 ah shore charger in your system and a 2000w would definitely be worth it. It is actually more efficient to charge my batteries by energizing my 40 ah shore charger than the built in charging circuit in the generator. I do not have air conditioning, but have 12v refrigeration and all the other amenities and use about 120 ah a day in my electricity budget during my active cruising. Because of the charge acceptance rate of the bank that is sensed by a "smart charger" , the generator usually cuts back to "eco" mode (quieter and slower) within an hour of starting and, depending on how much actual cruising I was doing (charging with the 105 ah alternator and smart charger) I ran it for a few hours more--because of the tapering charge rate of smart chargers it never tops off, so I have a 65w solar panel that does a fine job of that. In 'eco" mode you could not hear the generator two boat lengths away. It weighs something like 29 lbs. On the whole it is quieter than the windmills I experienced in the anchorages in Central America.

I think there is a tendency for folks to buy the 2000w version and lug it around without doing the math and figuring how their system will really work. To be sure folks have different tastes and different systems. My point is don't get carried away with bigger is better. Size to your needs. And be respectful of those of us who choose to live smaller when you pull into an anchorage.