How does one operate the 110vac refrigerator while cruising and no shore power available? Do you run the generator constantly?
110vac refrigeration
- Thread starter Richard Olden
- Start date
I do not now but my boat new was set up to run that way on a 220 volt 2000 watt inverter.
They had two alternators and ran the engine while running the inverter.
Apparently it worked quite well.
They had two alternators and ran the engine while running the inverter.
Apparently it worked quite well.
Basicly you have a 12 volt system (solar, wind, alternator and batteries) that handle your electrical loads while away from shore power. When on shore power the battery charger turns 120 volt to 12 volt to keep from draining your batteries.
If you have 120 volt appliances you would need to convert 12 dc to 120 ac to run them off the batteries (or as you noted run a genset all the time) There is a device that converts dc to ac and 12 to 120 volt called an inverter. It is not a great solution as there are losses in the conversion process. Given that the reefer is one of the biggest power users on your boat it makes sense to make its power supply as efficient as possible and use 12 volts directly.
If you have 120 volt appliances you would need to convert 12 dc to 120 ac to run them off the batteries (or as you noted run a genset all the time) There is a device that converts dc to ac and 12 to 120 volt called an inverter. It is not a great solution as there are losses in the conversion process. Given that the reefer is one of the biggest power users on your boat it makes sense to make its power supply as efficient as possible and use 12 volts directly.
You may be looking at the idea you could buy several 110 V fridges for the price of one 12 V fridge.
Good idea initially, but with the inverter in place, you would have a very short operating period before your batteries were discharged (to 50% of rated capacity) due to the electrical inefficiency.
I have always wondered why 12v fridges for boats/RV's are so so much more expensive than say a similar sized 110-120v dorm sized model like people buy for keeping the garage beer cold. Plenty of those available from $100 - $200.
Couldn't a manufacturer just replace the 110v compressor motor for with 12V motor instead? The manufacturer could even put in two motors one AC and one DC for the owner to switch around depending on whether at a 110AC berth or out on water with only 12V.
And still would be a lot cheaper than every marine dual sourced 12v or 110v.
But also I guess boaters can't risk an inferior model going bad while on a trans-oceanic crossing.
It is economy in numbers. There are tens of thousands of 110 volt fridges produced for each 12 volt marine fridge made. The same would be true of a dual motor fridge.
You run it on an inverter. Now you have to size the inverter and your battery bank to be able to run the refrigerator for the anticipated time. The average refrigerator will consume approximately 4 ah which in 24 hours will translate to roughly 100 Amps. The inverter also needs enough power to start the compressor so I would say you could do it with a 1500 Watt inverter and a 210 ah battery bank. Understand that other power usage will reduce the number of hours and that you will need to recharge on a daily basis.
Some boats were rigged with an engine drive refer system AND a 110v "shore assist" system. The engine drive can provide 12 to 18 hours of cooling in 1/2 hour of run time. Run the engine once or twice a day to chill the holding plates, charge batts and make hot water. The 110v system was then used when at the dock.
On my boat, a 12 volt system was a direct drop in for the 110v shore assist. So now I have the engine drive and the 11 volt systems. Works fantastic. Nice having redundancy tho we havent needed it. The engine drive system takes some of the load off the 12 v system when we drop the hook. Gives us many many options for keeping the meat and ice cubes frozen.
On my boat, a 12 volt system was a direct drop in for the 110v shore assist. So now I have the engine drive and the 11 volt systems. Works fantastic. Nice having redundancy tho we havent needed it. The engine drive system takes some of the load off the 12 v system when we drop the hook. Gives us many many options for keeping the meat and ice cubes frozen.