Polygeneration systems transform available primary energy into different types of final energy. Many available technologies for utilization of fossil and renewable energy sources (RES) for decentralized energy production imply the problem of optimal polygeneration technology.In this paper, a methodology for techno-economic optimisation of configuration and capacity of polygeneration systems based on RES is presented, based on research results. The methodology is tested on two real objects: an indoor swimming pool building and a livestock farm. Physical and mathematical models of dynamic behaviour of demand and supply of final energy of real objects and cost function of polygeneration systems are created for testing optimization methods. Validation is done by real object measurements, while mathematical and optimization models are solved numerically using TRNSYS and Genopt software. GenOpt algorytms were tested during optimisation of real object problems, and the best algorytm