The main purpose of the study was to identify the level and factors influencing investments in renewable energy sources (RES) in basic local government units in rural areas. The specific objectives were to define the conditions for the development of renewable energy sources in Poland, to determine the directions of changes as well as the importance of renewable energy in Poland, to present the relationship between the level of expenditure on renewable energy and budget components in rural and rural-urban communes. The Świętokrzyskie voivodeship (Voivodship—a unit of the highest administration level in Poland, since 1990 a unit of the primary territorial division of government administration, since 1999 also a unit of local government, there were 16 voivodships in Poland), which is one of the centrally located voivodeships in Poland, was purposefully selected for the research. The research period covered the years 2016−2019. The sources of materials were the literature on the subject, as well as empirical materials obtained at the Voivodeship Statistical Office. The following methods were used for the analysis and presentation of materials: descriptive, tabular, graphical, Gini concentration coefficient, Lorenz concentration curve, Kendall’s tau correlation coefficient and Spearman’s rank correlation coefficient. Poland is one of the countries with quite high dependence on hard and brown coal. Changes in the structure of energy sources are slow. Investments in renewable energy are necessary. The problem in this respect is the lack of a proper law. Despite this, investments in renewable energy are being made in rural areas. In the Świętokrzyskie voivodeship, only 28% of communes made such investments. It was found that only in urban rural communes the amount of investment expenditures in renewable energy sources was related to the level of budget expenditures and property expenditures of the commune. The amount of support from the European Union aid funds was positively correlated with the level of expenditure on investments in renewable energy. Therefore, it can be concluded that without the support from EU funds, it is not possible to invest in renewable energy in local government units.