How many Amp Hours do you have in your house bank?

[Tim Good]

My (MPPT) controller has a program-controlled output. Everything except the fridge is simply connected to the battery. The fridge is connected to the controlled output, and I can set the switch-on and switch-off voltages independently.

Hmmm I think mine also does. I might investigate doing this also. Thanks.

 

[macd]

Hmmm I think mine also does. I might investigate doing this also. Thanks.

I'd do so with caution, northcave, depending on conditions. On a typical day in the UK, your fridge might not switch on at all. (Not that it needs to for much of this week :ambivalence

 

[RupertW]

100AH, but we don't really need so much.

We get by in Greece from April to end September by only having the fridge as a serious consumer. Otherwise, instruments, tablets, phones, lights consume less than 1 or 2 amps in total. The fridge is programmed to only come on when the voltage is 13.something, and switches off when it drops below 12.8. Typically it works from 9:30 till 18:00. Stuff is still cold in the morning.

We have a nominal 300W of solar panels, but they are fixed, so the efficiency is low.

TonyMS

We have 200Ah and that is more than ample for our cruising so far which is limited in time meaning we travel almost every day so the engine does the job, particularly as we don't have 12v fridge just a very powerful engine driven one with a big thick plate that stays iced for 12 hours after being switched off.

But I do expect to install solar and double the bank size when we finally fit a 12v compressor and extra plate. No problem with me fitting an MPPT, panels or wiring but for two winters in a row we have commissioned different boatyards to fit an arch an in both cases they were enthusiastic then went to ground for the Winter without even quoting. Onwards to next year.

 

[doug748]

100AH, but we don't really need so much.

We get by in Greece from April to end September by only having the fridge as a serious consumer. Otherwise, instruments, tablets, phones, lights consume less than 1 or 2 amps in total. The fridge is programmed to only come on when the voltage is 13.something, and switches off when it drops below 12.8. Typically it works from 9:30 till 18:00. Stuff is still cold in the morning.

We have a nominal 300W of solar panels, but they are fixed, so the efficiency is low.

TonyMS

That is interesting to know.

I was once told, on here, that my domestic bank was too small at 110Ah despite the correspondent knowing nothing about my sailing, equipment level or pattern of use.

 

[Tranona]

That is interesting to know.

I was once told, on here, that my domestic bank was too small at 110Ah despite the correspondent knowing nothing about my sailing, equipment level or pattern of use.

See post#9 - not that I am claiming any special credit for suggesting what seems obvious and logical.

 

[doug748]

Indeed,

"Annual income twenty pounds, annual expenditure nineteen pounds nineteen shillings and six pence, result happiness. Annual income twenty pounds, annual expenditure twenty pounds ought and six, result misery."

 

[silver-fox]

600 AH cheap, sealed, lead acid truck batteries.

 

[geem]

1000amp hr of open cell truck batteries. Battery box built for them from new. Typically 12.7-12.8v by morning with fridge n anchor light over night. Domestic Batteries are 4x 65kg each.

 

[KellysEye]

House batteries should be deep cycle not CCA. We used two Trojan T125s wired in series 240AH: https://www.hardwarexpress.co.uk/t-...MI-7rulOXK2QIVhpUbCh3vpQJrEAQYASABEgIcd_D_BwE

 

[geem]

House batteries should be deep cycle not CCA. We used two Trojan T125s wired in series 240AH: https://www.hardwarexpress.co.uk/t-...MI-7rulOXK2QIVhpUbCh3vpQJrEAQYASABEgIcd_D_BwE

You dont need deep cycle batteries if you dont deep cycle. Instal enough capacity so they dont cycle. At 0600 local time in the Bahamas my battery voltage was 12.7v. The fridge and anchor light have been on all night. Your capacity is 1/4 of mine. My fridge is super efficient as is my mast head anchor light. Cut your load and install as much battery capacity as is practicably possible and you dont need expensive deep cycle batteries. We are fortunate that the boat was designed with a very large battery box. We actually have space for more batteries in the box but dont feel the need.....