The article addresses issues related to planning investments based on renewable energy resource, as exemplified by solar energy. In the first part mean annual amounts of total solar irradiance in Poland are presented and legal conditions for development of this kind of technology with reference to the European Union regulations and to the Renewable Energy Resources Act of 20 February 2015. In the next part of the paper a distribution model of direct solar irradiance for the town and community (gmina) of Jordanów has been constructed. Mountainous character of this area, located in the south part of the Małopolskie voivodeship, means there are very good as well as very bad conditions of insolation. The results obtained by using the model were assigned to building plots and plots intended for development and than they were analysed with the aim of choosing optimal areas for green investments based on solar energy.