How to achieve KfW40? Energy technology / Economic efficiency

Do you also still know about the above-mentioned statement that when utilizing e.g. Kfw40Plus, another e.g. storage subsidy (in our case the state of Saxony) MAY NOT be claimed?

No, I do not know specifically. But with KfW it is generally stated that double funding is excluded. For example, here in NRW I can have my wallbox funded by the state or by the KfW. Both together is not possible. I also cannot imagine that double funding would be approved anywhere.

Regarding double funding, I think (but I'm not quite sure) that at least the entire construction is funded with KfW40+ (where a battery storage system is mandatory), but an additional subsidy of 200€ per kWh for the battery storage is still possible (here in NRW). At least all the applications have been submitted and already approved! However, double funding is definitely not possible for wallboxes.

additional support for the battery storage with €200 per kWh is possible (here in NRW).

it seems to be the same in Saxony. Let's see...