After 2.5 yrs with OVO, the new App and website has allowed me to see the usage figures for my electricity usage for the first time… (it was blank and no one wanted or was able to fix it!).
I have a 1.2kW PV installation and am also part of the V2G project, so my Nissan Leaf export about 10-15 kWh per day back to the grid.
My IHD therefore often shows a negative figure because we are not using all the PV or the car is exporting (generally around 3kW per hour when operational).
Looking at my usage figures, there are no negative values and almost no values of zero… so I surmise that the meter must log into the export data list when the power is negative and restarts logging when it its positive... This means that even on a sunny day, if the usage in the house tops the 1kW we are producing for 1 second, we will get a positive reading on the usage graph… To get a zero reading, we will need to supply a negative value for 1800 seconds of the each 30 minute window.
This raises some interesting questions about the export figures because without them the usage figures are meaningless, as they do not actually show what I have used… it would be very interesting to see them and start to analyse the real usage including what the car is doing and what the PV is doing…. is there any way to access this data? Clearly it must be available, because OVO use it to pay me for the power they take from the car!