Commentary on Sections Section 84: Power to amend licence conditions etc: transmission systems
442.This section gives the Secretary of State the power to modify, for the purposes described below:
	a particular electricity generation, transmission, distribution or supply licence (subsection (1)(a));
	standard licence conditions of those types of electricity licence (subsection (1)(b)); and
	documents maintained under the licence conditions of relevant electricity licences – for example, industry codes (subsection (1)(c)).
443.Subsection (2) sets out the scope of the modification power. The power may only be exercised for the purpose of facilitating access to and/or efficient use of a transmission system in Great Britain or offshore waters.
444.Subsections (3)(a) and (c) allow the modification power to be exercised differently in different cases or circumstances. This could, for example, allow the Secretary of State to make different modifications in relation to generation under development and generation that is already connected to the network.
445.Subsection (3)(d) makes provision for the Secretary of State to make any incidental, supplementary, consequential or transitional modifications to licence conditions or documents of the kind mentioned in subsection (1)(c).
446.By virtue of subsection (4) the modification power may not be exercised after the end of the period of 2 years beginning with the day on which subsection (1) comes into force. Subsection (1) comes into force on such day as is appointed by order of the Secretary of State (see section 110(2)).
447.Subsection (5) ensures that, where the power under subsection (1) to make modifications is exercised, certain general provisions of the Electricity Act 1989 which are relevant to this power are applicable. For example, the modifications can require the licence holder to comply with directions by the Secretary of State or the Authority as to specified matters.