Q: We originally installed 7.23 kW Solar PV for our home a few years back that qualified for the higher band of feed-in tariff (FIT). Just this month we have installed an extension of an additional 15 kW. We understood this to be an extension to the original system and that the extension would be eligible for the current rate of FIT. We also obtained an EPC (energy performance certificate) that showed our home to be rated at C (80). Today we completed the E.ON FiT application and went to hand deliver it to their office in Bedford. We've been told that this extension is only able to qualify for the lower rate of FiT (7.1p), since apparently the rules state that showing the EPC certificate at the time of the application is only applicable to new applications. I've tried to find information on this on the EST website but it only refers to new applications. Are you able to confirm where we should stand on this as I feel that E.ON are mis-informing us.

A: I was rather surprised to hear this story, as your original installation was before the EPC requirement came in, so you wouldn't have shown an EPC then. A little digging indicates that the nub of issue seems to be about what stage you had EPC done for the extension of your PV system.

I asked Ofgem for their interpretation of the rules, and this is what a spokesman said:

“This is likely to be a question of when the EPC was issued. A FIT installation is only eligible to receive the higher tariff rate if the EPC is issued on or before its Commissioning Date. For an extension to an existing FIT installation the date from which FIT payments can begin (when it is installed and MCS-certified) known as its Eligibility Date, is considered its Commissioning Date. If the EPC is dated after that date it is treated in the same way as a new application without a valid EPC or exemption letter.”

So, as I understand it, if your EPC was dated before the eligibility date of the extension, you should be eligible for the higher tariff rate. If it was after, you'd get the lower rate. Do let us know how you get on with E.ON.

Photo by Simon Kay

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