This paper presents the possibility of utilizing distributed generation (DG), including renewable energy sources, for electricity production in low-energy housing construction. The Directive on Energy Performance of Buildings (EPBD) defines a building with nearly zero energy consumption as a building with high energy effectiveness. Very low or almost zero energy requirements of the building should be covered, to a large extent, by onsite renewable energy sources. According to this Directive, after 2021, only the construction of buildings with very low energy demand powered by renewable energy sources will be allowed within the European Union. The paper also presents the problems resulting from the emergence of large amounts of distributed generation in the power system. A large number of DG over a small area in the coming years could prove to be a challenge for the power system. Hence, the need now is to determine the possibility of connecting small sources to the grid and to use the potential of “Smart Grid”. If Poland wishes to meet the requirements of the EU Directive which requires that by 2020 15% of our energy must come from renewable sources, it has to propose new legislative solutions which will ensure adherence to this limit. The proposed legislation that will support distributed energy resources to eliminate barriers for investors who want to build a small power source will make access to the grid by small producers easier. Ensuring the adaptation of distributed generation based on renewable sources of primary energy is an important factor for maintaining sustainable development. It also results in the need to reserve multiple sources, often of a stochastic production system, thus limiting the risk of disruption of electricity supply. This condition will require substantial reengineering of the power system. It is also necessary to remake the network of business management methods in order to permit proper interpretation of the vast amount of associated information and use it to develop optimal decisions in the proper time frame. Hence, the need arises to implement the comprehensive intelligent energy system called “Smart Grid”.