A renewables obligation order may provide that—
in such cases as may be specified in the order, and
subject to such conditions as may be so specified,
an electricity supplier may (to the extent provided for in accordance with the order) discharge its renewables obligation (or its obligation in relation to a particular period) by the production to the Authority of a Northern Ireland certificate.
In this section "Northern Ireland certificate" means a certificate issued by the Northern Ireland authority in accordance with provision included, by virtue of Articles 54 to 54D of the Energy (Northern Ireland) Order 2003, in an order under Article 52 of that Order (renewables obligations for Northern Ireland suppliers).