I have had photovoltaic cells installed on the roof of my house in East Anglia (UK) and was interested in tracking how well they were working on the (not too) sunny days we get in England. Two sets of panels have been installed, one at 110 Degrees (south of east) and the second at 200 degrees (just west of south) and because each bank of panels will be connected to it’s own inverter and I am able to measure the amount of power being generated from each bank separately.

The table below is updated about every 5 minutes and shows the current instantaneous power, the peak power and the total power generated since the measuring system was install. The other charts display the power generated over that last 30 hours (updated hourly) and 30 days (updated daily). At a later time I may add a month by month chart.

Health warning: This data can only used as a guide because the measuring devices only return an approximate power reading.

I have now installed an immersion heater in my hot water tank to use the surplus power from my solar panel to heat the water. I have upgraded the intelligent switch that switches on the immersion heater when I’m exporting, the new switch switches on quicker and in finer steps. See For further details and power used is included in the generation graphs below but unfortunately the senor is confused by the regulated power fed to the heater and is wrong; so for present I will be doing manual updates to the daily and weekly graphs.