Not sure what you mean by "can drift something" but if you mean "drive" or "power" then here's my guestimate at it - but I'm new to these kind of calculations so you might want to get these checked out by someone with more experience with battery banks...
47kWh/day is 1958.333Watts continuous. At 240v that's 8.160Amps continuous load. Assuming an inverter efficiency of 80% that's about a 10.2Amp draw on the batteries. So a 916Ah bank should last for around 90 hours without recharge.
Corrections to the above welcome - I want to learn how you folks calculate this!
That's close, but you forgot to convert the voltage so;
10.2A*240/48=51A@48V then 916/51*.9(line losses estimate)=16.16hrs, but probably less due to voltage drift as the batteries come down, so my non-expert opinion would be around 12 hrs.
Location: Bristol - UK
posted 3 years ago
Yeah, thanks Bill, I did forget to convert between voltages.