Someone asked how we get the data about our power generation and usage to the side of our website. Well here is as concise an answer as I can manage. Here’s a schematic –
Power comes from our PV Panel Arrays (shown top). The big array (centre) is wired as 4 groups of 6x 80w panels, with the 4 groups in parallel, so the array puts out 6×22.5v = 135v and 4x6A = 24A. The array to the right is wired as 4 groups of 4x80w panels, with 4 groups in parallel, so the array puts out 4×22.5 = 90V and 4x6A = 24A. The small array to the top left is wired as 2 groups of 4x100w panels with 2 groups in parallel, so the array puts out 4×22.5v = 90v and 2x6A = 12A. These are connected to 3 MPPT Controllers – a Victron 15/70, a Victron 100/50 and a Victron 100/30, which charge our battery bank.
At the heart of our system is an inverter/charger, that feeds power from the batteries to the house, which is wired conventionally, except for the circuits being split into 2 – one for lights, solar and central heating pumps and a couple of sockets, and another circuit for all other sockets. This allows us to have less important things disconnect automatically by the inverter – known as load shedding.
Connected to both, is a battery monitor, that looks at the state of the batteries, as well as the flow of current in and out of them.
The Charge Controllers, Inverter, and Battery monitor are all connected to this control unit –
Which is connected by our internet router to the Victron VRM website and database. Because Victron open source their code, we have been able to write some custom code to allow the data to be displayed on our site. This may all seem like a lot of equipment, but the Battery Monitor and the Color Control have made a huge difference to the way we use power. Ok, at the moment we are still faffing with panels and kit, so sometimes it all goes out the window as we fire up an arc welder or whatever, but it won’t be long before we have the storage capacity to deal with it all.
Our baseline consumption is still in the order of a couple of hundred watts max, so the challenge is to cope with the peaks caused by larger appliances, and of course, to reduce the amount that those appliances need in the first place by choosing wisely.