Definitely comes under "nice problem to have" 😅.   https://www.gov.uk/hmrc-internal-manuals/business-income-manual/bim40520 says   > The term ‘significantly exceed’ in (b) above is not defined in Section 782A and should be considered by reference to the particular circumstances. However, in general, a householder who does not intend to generate an amount of electricity more than 20% in excess of their own domestic needs is unlikely to be regarded as intending to significan