I am currently in the process of installing a ESS for my house using a Multiplus 5kVa 48v unit and currently 2 x 2nd hand Tesla 5.26kWh battery modules with the intention of adding more modules before winter. So far so good but I am still in the testing phase of the install. Other key electrical items in the house are a ASHP (3kW input), solar PV (5.7kW output), double oven (5.7kW input) induction hob (3kW avg input, 4.4kW max). I had the PV system installed about a year ago of which we are not using as much of the energy generated as we could so I decided like many people to have batteries fitted to better us the PV generation more. The intention is to use as little or no grid energy as possible for most of the year.
The install is still a work in progress with a lot of testing, as using 2nd batteries from a car is not generally a industry accepted method. items remaining are adding 2 more batteries, make and fit an enclosure to the batteries to help maintain temperature, provide heat and smoke detectors (rather be safe), reconnect the batteries pipe connected to a new heating / cooling system with a 100W heating element for keeping the batteries warm in the winter, and a fan assisted radiator for heat rejection in the summer. Another aspect being worked out is how to better balance the loads to utilise the PV output and inverter output better. I have all my other CT sensors turning up this week along with my grid meter. I'll upload another post when I have a completed system with 4 battery modules hopefully with a DC schematic and a copy of my final commissioned settings for the inverter as I learn how best to use the system.