We currently have an amazing system, 32 PV panels and 2 x 8.2kwh Batteries.
The charge and discharge are only 3kw, Is it possible to improve this?
Also, I am thinking of adding more Batteries as we also have an ASHP
How many Batteries is the maximum allowed and what's the best way to manage this.
Thanks.
AllenHart What sort of inverters do you have? We have the same number of panels and batteries but split into two systems, each with its own HY5.
I think you need to have a long think about what it is that you want from such a large system. You could charge up more batteries (I think the maximum is 4 for each hybrid inverter) from PV but you're unlikely to be able to do that for much more than the summer months, when your ASHP (assuming it's not doing cooling duties) is doing least work. By late autumn through to early spring, you'd be lucky to consistently fully charge the existing batteries every day from PV.
Alternatively, if you have an EV, you could sign up to an EV tariff with an off-peak overnight rate. Ours is with EdF and they offer 5 hours each night. If you've got 8.2kWh batteries, I assume you've also got gen1 inverters, the same as us and can charge batteries at 2.5kW. The off-peak window is long enough to fully charge the exiting batteries each night if there's no energy from PV during the day. A Gen2 inverter can charge at 3.6kW and so with a 5 hour window, could push about 18kWh into a set of batteries each night. However, if yours is/are gen 1, then you're limited to 2.5x5=12.5kWh. So although another battery would give you more capacity, you might struggle to charge it sufficiently off-peak to meet your needs each day. Still, if you added another two batteries, it would give you a potential charge capacity of 25kWh. Only you know whether this would be sufficient to meet your needs during the winter.
The other thing is that I suspect that off-peak tariffs are not going to be around forever. Once more people have EVs and everyone wants to charge at off-peak, shifting load will have to be done more granularly and I think tariffs like Octopus Agile which can vary prices every half hour are going to become the norm.