I have a system (2 x 5Kw Multiplus II, 45KWh batteries) which is predominantly an ESS designed to buy power cheap then use it at peak, but it is supplemented by a small 7 panel solar array.
My tariff is 5p overnight 1am-6am, 14p 0930-1130 and 14p 2030-2230, and 23p all other times.
We heat using an ASHP so in the winter we use way more than the batteries can provide, in the summer we can often go a whole day on one battery charge.
I used to just charge to 100% overnight, then leave it be. But, on sunny days, there is a risk there won’t be enough space in the battery to take a small solar charge. So I was interested in adapting the charge depending on a prediction of forthcoming solar.
So I am trying Dynamic ESS however, it is not proving very successful, even though my use case is fairly straightforward. I have had it on for almost 2 months and I am pretty sure it’s costing me a more than what I used to do! For example, the day attached.
Despite it being clear that I should have survived almost completely on the battery all day, it was still topping up during the 14p periods, which then means, when I get to the end of the day, I forgo the better 5p rate overnight. And also, it was drawing from grid in the 14p periods in preference to using up the battery that I had bought in at 5p.
What am I doing wrong, or is Dynamic ESS just poor and to be switched off?
If a Victron person is reading this it’d be really appreciated if someone could have a proper look into my account.
