I couldn’t say specifics without knowing about the transformer, but the chances are that it really cannot handle the extra demand on it...

Transformers in these rural area's often are paid for by the people who need the supply, or at least part of the cost, and the REC are not likely to fit anything much bigger than it needs to be

I would say that I'm not at all surprised by what they have said..

Actually pluggie I can see some logic in the RECs position, surprising though it may be.

If the leccy company upgrade a transformer which serves many homes then it stands to reason that they will get payback quickly from providing power to all those homes.

Whereas upgrading a transformer to serve just one or two properties means that the cost would have to be distributed across the entire region. Would I want to pay for an upgrade to some remote rural cottage when I live in the suburbs? No I wouldn't.

It would be a real shame if that transformer suffered a catastrophe though.....they'd have to replace it. Can't you get a friendly farmer to swipe it with his tractor as he's going past?

HM

The rule is that you can increase your maximum power requirement by up to 25% for free. Once only.

The chances of the DNO having your original application, on which you would have stated the power requirement, is zilch, so think of a number you can currently take, say you want 25% more & they will have to upgrade for free.

Oh ye of little faith -

Read about it on the DNO's web site. You need to look for "Connection Statement" - the terms for connection which they are required to publish under  their distribution  licence.
Then find "Reinfoircement" for the  terms for reinforcement.

As  an example, here is EDF's for London:

Reinforcement of the existing system (which for this purpose means works occasioned by the new or augmented connection, but not required for its sole use) will be included in the connection charge, subject to the following:

No charge will normally be made for reinforcement of the existing distribution system if the new or increased load requirement does not exceed 25% of the existing effective capacity at the relevant points on the system (the ‘25% rule’).

NOTE 1: Previous related increases will be taken into account in deciding whether the aggregate load requirement meets the 25% rule. NOTE 2: Where we have reason to believe that an application for connection forms part of a larger project we will use the aggregate capacity of the