Article 4 2.

Each Member State shall set an indicative national energy efficiency contribution based on final energy consumption to meet, collectively, the Union’s binding final energy consumption target referred to in paragraph 1 of this Article and shall make efforts to contribute collectively to the Union’s indicative primary energy consumption target referred to in that paragraph. Member States shall notify those contributions to the Commission, together with an indicative trajectory for those contributions, as part of the updates of their integrated national energy and climate plans submitted pursuant to Article 14(2) of Regulation (EU) 2018/1999, and of their integrated national energy and climate plans notified pursuant to Article 3 and Articles 7 to 12 of that Regulation. When doing so, Member States shall also express their contributions in terms of an absolute level of primary energy consumption in 2030. When setting their indicative national energy efficiency contributions, Member States shall take into account the requirements set out in paragraph 3 of this Article and explain how, and on the basis of which data, the contributions have been calculated. To that end, they may use the formula set out in Annex I to this Directive.