The act came into force on 1 January 2018.The purpose of the Energy Market Act of 8 December 2017 is to introduce a regulatory solution that is designed to satisfy the shortage of power generation capacity. The Act introduces a new model of a centralized energy market. In this model, a central purchaser – power distribution system operator – is committed to supply the system with power level adequate for specific situations and stay ready to provide it. The Act regulates the organization of the so-called primary market - power auction - and secondary market - bilateral transactions between suppliers. The introduction of a new institution in the form of the energy market entails significant changes in the functioning of the power generation sector.