On the 23rd November 2011 we have had a 2.9Kwp solar PV installed.
We recently got our first payment from the UK's governments Feed In Tariff scheme. This has prompted me to take stock of how the system has been performing and how the data collected using the OpenEnergyMonitor energy monitoring system compares to the utility company's billing meter:
From the 23rd Nov 2011 - 23rd Nov 2012 the billing utility meter on the solar PV system has recorded a generation of 2069 kWh. Over the same period we consumed 3588 Kwh, 57% of our electrical energy needs have been met by the solar PV.
At this rate it looks like we're on track for the system to pay back in 7-8 years, maybe even less if we have some more sun in the next few years, fingers crossed!
For the same time period the OpenEnergyMonitor monitoring system has recorded a generation of 2029 kWh, giving the energy monitor an accuracy of 98%!
The monitoring system is a standard emonTx with an AC-AC adapter taking Real Power readings.
|One Year of PV Generation|
|Kwh/d Electricity Consumption (orange) Overlaid with Generation (blue)|
When the system was installed the solar PV company estimated we would produce 2434 Kwh per year, we generated 15% less than this estimate. This could partly be attributed to the very poor summer we experienced in 2012.
This year is already looking promising, on the 2nd of May 2013 our system generated a record (for us) of 18.3 Kwh 1.9 times more than we consumed on that day (9.7 Kwh):
|Record Generation on 2nd May 2013|