The Electricity Generators (Rateable Values) Order 1989
By virtue of section 3(1) of Schedule 6 to the Local Government Finance Act 1988, where the Secretary of State so provides by order, hereditaments of a description to be prescribed in the order are not to be valued for non-domestic rating on and after 1st April 1990 on the basis set out in paragraphs 2 to 2B of that Schedule (that is to say, by reference to the rent a hypothetical tenant would pay for the hereditament on an annual basis), but on the basis of prescribed rules.