Case C-612/21, Gmina O.: Judgment of the Court (Seventh Chamber) of 30 March 2023 (request for a preliminary ruling from the Naczelny Sąd Administracyjny — Poland) — Gmina O. v Dyrektor Krajowej Informacji Skarbowej (Reference for a preliminary ruling — Taxation — Value added tax (VAT) — Directive 2006/112/EC — Article 2(1)(a) and (c) — Supply of goods and services for consideration — Article 9(1) — Meanings of ‘taxable person’ and ‘economic activity’ — Municipality which organises the installation of renewable energy on its territory for its residents who own immovable property and who have expressed the wish to be equipped with renewable energy systems — Their contribution amounting to 25 % of the subsidisable costs, without being able to exceed a maximum value agreed between the municipality and the interested property owner — Reimbursement of the municipality by a subsidy from the competent provincial authority of 75 % of the subsidisable costs — Article 13(1) — Municipalities not subject to tax for the activities or transactions carried out as public authorities)