Max power from Giv-HY 5.0 Inverter, from battery.

I am currently in the process of getting quotes to install a solar PV system, with a battery. The installer has quoted for a Giv-HY 5.0 'G2' (so I assume 2nd gen variant) inverter.

Looking at the datasheet for the inverter and the paired battery, it looks like the maximum power available from the battery alone (so later in the day, when no solar generation), would be just 3.6kW. So if my house load is 4.4kW (two ovens in use), I would presumably still be importing 0.8kW from the grid.

Have I understood the datasheet correctly, or can the inverter actually supply the full 5.0kW from the battery alone?

2nd Question
I'm also considering if I could run two batteries and two inverters in a parallel, so that if one should fail, I would still have 50% of the system in operation (assuming the faulty side was isolated). I will have two solar strings, so each could be connected to its own inverter/battery pair. Can this be done, or are there good reasons not to go down this route (apart from the higher price)?

Thanks

Chris

ToothyChris I have a 5kw inverter and my system can only use 2.6 from the battery. During the day this is rarely a problem, but at night it’s easy to blow the limit for short periods

The question is how much £ is it worth spending to stop this when in fact you can’t get to a situation where you use no grid energy, because the system relies on it while the battery ramps up for a few seconds. Basically the grid energy is instantly available, but batteries take time to take over when the demand increases. Two batteries and inverters would be nice but is a more complex system, doing that in case things go wrong would not make financial sense, but doing it to double your output is a better argument.

I think it’s worth thinking about the system more like a bank account, you pay in and make withdrawals but it’s the overall balance that matters. In March and April I used about 50 kw but exported 300 so happy days.

In fairness I fudged my Gen 1 up to 5kW on battery only (via a separate inverter on the PV side) but very rarely does it get pulled in to service so the Gen2 is pretty much the sweet spot in all honesty (you'll find your oven elements will switch in and out independently of one another after they've warmed up so you won't realistically be pulling from the grid much for long)

ToothyChris I went through the same thought process and settled on a gen 2 5kw hybrid inverter and 2 of the new 9.5 batteries. This config will apparently allow up to 3.6kw draw.
We had a smart meter installed a couple of weeks ago and I've been watching the power draw of various appliances. Other than the kids electric shower, with some easy scheduling of other appliances, 3.6kw will suffice well over 90% of the time. The rest is just very short peaks. It doesn't allow us to be 100% independent from the grid (yet) but it's close enough. It's a 4 bed house with 4 occupants.

Thanks all for your comments/feedback. So it looks like my understanding of the datasheet is correct.

@hoggy Your comment about the two heating elements switching in and out is quite valid. and not one which had occurred to me.

I am not really doing this to save money, as such, so I would be happy to spend a bit more than absolutely necessary. Having poked around a bit, it does seem possible to have two parallel systems - another reason for doing this is that I assume I would get individual control of each system, though the app, so one battery could focus on charging up from cheap overnight grid power, while the other battery is focused on the solar charging.

I'll see what my installer says in response to my request.

Many thanks.

TC