Member States shall clearly define any technical specifications which are to be met by renewable energy equipment and systems in order to benefit from support schemes and to be eligible under public procurement. Where harmonised standards or European standards exist, including technical reference systems established by the European standardisation organisations, such technical specifications shall be expressed in terms of those standards. Precedence shall be given to harmonised standards, the references of which have been published in the
Official Journal of the European Union in support of Union law, including Regulation (EU) 2017/1369 of the European Parliament and of the Council (
14
) and Directive 2009/125/EC of the European Parliament and of the Council (
15
). In their absence, other harmonised standards and European standards shall be used, in that order. Such technical specifications shall not prescribe where the equipment and systems are to be certified and shall not impede the proper functioning of the internal market.