I`ve been using DESS now for about 2 weeks in green mode and is does what it suppose to do. It uses the battery for self consumption and discharges to the grid with access power. The only thing it does not do is charge the battery from the grid, even when the prices are the lowest at the day.
What I do now is switch the ESS to keep batteries charged manually at the time the power is the cheapest and set it back to normal operating mode when the prices are rising again.
Would be nice to have an option where you could set a price level on weekdays/weekends to automaticly charge the battery when thea price is hit.
Two things to consider. 1. There needs to be a certain price difference to pre-charge the storage. This takes into account a certain level of efficiency and the cost per battery cycle. In my case it’s around 6 cents per kWh if I take both into account. The system uses any PV surplus to cover the most expensive times and only when times remain with a higher price difference does the system pre-charge energy. 2. The system only ever takes into account the period when prices are available. Personally, I always speculate a little on the prices for the coming week. At particularly cheap times on the weekend, I set the minimum SOC a little higher and thus store energy in the storage. On days with high prices during the week, I then release some of this energy as needed, which the system then uses at particularly expensive times.
But these are all manual action. I would like to see that you can set values as what it considere to be able high and low proce or maybe when you click on a hourly block you can then selectbcharge or dischatge battery so you can easiky overule the Dess schedule
You should calculate the battery cycle costs, round trip efficiency losses and what you pay additionally to your supplier as service fee. Only then it can charge your battery from the grid. Conditionally. When the price difference is high enough.