A blog all about the 3kWp PV Solar panels installed in Nov 2011 in Kent UK by Solar Advanced Systems. Follow the ongoing performance and how much solar power we generate over the next few months as well as the problems and solutions we encounter along the way such as solar panels electric meter going backwards.
We are registered with British Gas for our FIT payments and our roof is SSW facing. We have 14 x Sungrid 215W solar panels and Sunny Boy 3000HF inverter.
The inflation rate for December 2017 has just been released today which means that the level of Feed in Tariff for 2018/2019 is now known.
The Feed in Tariff (FIT) rate for April onwards is based on RPI inflation rate for the previous December so the 2017 figure will determine the FIT tariff payment level from April 2018.
The FIT tariff level for 2017-2018 was 50.67p per kWh for generation and 3.57p per kWh for export which is deemed as 50% of the electricity generated.
The headline figure of CPI inflation for December 2017 was 3.0% but this isn't the number used to calculate the Feed in Tariff FIT level, the value needed is for RPI inflation which is much harder to find as it's no longer considered an "official" national statistic.
Solar PV generation meter - FIT rates 2018/19
Delving into the ONS statistics page it's eventually possible to locate the RPI number which is 4.1% for December 2017.
I've been a bit slow to update the data on my website over the past 12 months as it was becoming more tedious to do every month so I decided to batch it up. Unfortunately I subsequently discovered that the Sunny Boy inverter only holds 2 months of detailed daily data but full copies of the monthly summaries which means that a couple of months are lacking details. http://solar-panels-review.321web.co.uk/index.php/yearly-comparison-of-solar-pv
With another year added to the totals it's interesting to see how the months may vary by year but often a bad month will be balanced out by a better month the same year so the overall totals are much closer that you might expect. For example 2015 and 2017 were only 6kWh different at 3207kWh and 3213kWh respectively. What does seem clear is that the maximum days are dropping which might be expected as the solar panels age so in 2017 we only had 1 day with over 20kWh of electricity produced.