Having read my own post earlier it rather reads like the battery system is some sort of Alchemy, …which it clearly isn’t. The test setup was in addition to an existing 5kwp grid tied solar system. In charging the battery, it self-consumes until it is fully charged from available solar. Excess then feeds into the Tesla and the water. If the excess is not there, clearly there is potential for a flat Tesla or at least not fully charged, and less hot water than required. Hence the manual fine tuning. Any excess over this on a really good production day is fed back to the grid. During charging, the ESS limits import/export to around 100w either way pretty quickly.