Adding panels to an existing system

[SolarCity]

A pretty basic question here, but something we haven't come across before.

If a 4kWp is installed, as far as I understood it, and addition would then bring the original installation down to the rate of the new size FIT bracket: for example, add 2kWp and the whole system would now be on the 4-10kWp rate. Have I got this right?

 

[TedM]

No, the existing system always stays at its original rate. Only the new part over 4kW would be at the lower rate. Make sure you have the relevant EPC in place before the extension is added.

 

[SolarCity]

Thanks for that, Ted. So what is stopping someone installing and registering a 4kWp system and then simply installing another 6kWp the next day? Isn't this always a better option than simply installing 10kWp in one go?

 

[TedM]

I don't think there is anything stopping it. I believe that in the past a large number of big solar farms started off at just 50kW.

Originally FiTs had a 12 month period when any extension was treated as a change to the first system, to stop this sort of thing happening but the rules were changed in 2011. I guess OFGEM monitored things and decided it wasn't a real problem.

 

[SolarCity]

Thanks Ted, I appreciate the info.

 

[Gavin A]

I'd expect if you had 2 installs at the same address going through processing at the same time it'd flag up, either way I'd think it'd be fraud, so not worth the risk.

No problem in doing it with a bit of time in between if there's a good reason for it though, eg we've got one system that originally got installed under G83, then upgraded to 30kWp, then 50kWp, and shortly 150kWp, with the original being installed before the FIT cut while waiting for the G59 permission, 2nd bit before the next FIT cut, then 3rd bit when they decided they wanted a bit more, then next bit when the accountants realised how good an investment it had been.