Abstract
Purchasing groups are multi-entity organisations that operate in practically every sector. Their greatest role is to improve the financial situation of small and medium enterprises (SMEs). In the case of enterprises operating in the sectors that are just developing, especially those belonging to SMEs, it is particularly difficult to obtain favourable financial results. In Poland, such sectors include, among others, renewable energy, which is slowly developing, but has not yet reached the size set in climate policy. The purpose of the paper is to present how functioning under group purchasing organisations (GPOs) affects the profitability of companies related to the renewable energy sector. For the example of the largest industry purchasing groups, the analysis showed that high profitability results were achieved by enterprises operating in them compared to entities operating independently in the market. In total, 71 enterprises operating in the sector related to the renewable energy sector in Poland were analysed. The enterprises were divided into units operating in the purchasing groups of 46 enterprises, and those that operate independently in the market of 25 enterprises. The research period covered the years 2016−2019. The analysis showed that the scale effect allowed companies to increase profits and had a positive effect on their financial liquidity. The research proved that in the case of commercial enterprises operating in the sector related to renewable energy, functioning within the industry purchasing group allowed high profitability and financial liquidity. There is a dependency that the liquidity increases with a growth in profitability.