Trojan Boat Forum

Hello all,
Im sitting here again as I do every year and I'm contemplating what my next upgrade should be. I always try to better my craft a little more every season. More some seasons than others LOL but I digress. I own and operate a 1971 F-26 with the V-drive and backward engine. There is little to no room in the engine compartment for a even a small genset after upgraded fuel tanks. I do however have 4 group 29 marine batteries and a Xantrex Freedom 4000 watt marine inverter. The devices in the cabin to be powered would be an air conditioner, Fridge, coffee maker, microwave, TV, and Stove (obviously not all at the same time). I have attempted to see if there was enough juice to power all of these devices. I placed the batteries on a plank, then grouped two sets together and plugged them into the inverter I then using electrical cords pluged in my fridge, then turned on the A/C to dehumidify ( a/c wouldn't kick in as it was 50ish outside but compressor works the same in dehumidify mode), then tv. I walked away checking to see if all was well every half hour. At 4 hours i turned everything off. After some math I calculated that I had about 20% battery life in both banks left after 4 hours of use. If I put enough batteries in to give me 8 hours at 95lbs a battery I think i will end up with a trawler . Do lead acid weigh more than AGM or GEL Are there any other alternatives

This system is not connected to the engine batteries at all it is on its own, stand alone the inverter both charges and switches over as soon as shore power is unplugged.

Unfortunately you are probably not going to better your system much with batteries considering what you said you like to put power to. I have a similar amount of amp hours available to me and I always run the generator for larger loads like the stove or heat. Often enough I end up needing to charge batteries anyhow on longer trips even without using big load devices on the inverter.

I think the inverter is nice for some things. Charging electronics, watching a movie on TV, making a blender drink, coffee, etc.... When it comes to larger amp draw items like stove, heat/AC, or similar thhe generator is the way to go.

in my opinion one of the biggest issues is how are you going to recharge this? i know the engines but thats gone take a while.
i am a big advocate of inverters and have used them on every boat i've had including my sailboat.
i think you need to look into golf cart batteries as they will more than be double capacity of the grp 29 batteries you are currently using.
look at something like the trojan T105's or larger
also i would get something like this to actually measure what you are using from the batteries
http://www.victronenergy.com/battery-mo ... 0bmv-602s/

the only ac's that would be logical to use battery power would be either dometic dc unit or mermaids M5 5200 btu unit. i have this M5 and it is spec'd to run with an inverter. using it will be apx 50 amps dc while it is cooling, this is doable if the inverter bank is sized correctly. remember you only want to use 1/2 of the battery capacity so you will not shorten the overall life of the batteries.
i believe you could accomplish part of what you want to do and maybe all of it but you are going to half to know how much you have taken out of the battery bank. if you only achor out for 1 night then you could very well get away with no genset but more than that will require someway to recharge. imo

Get a bigger boat with a genset