As a result of environmental pollution, increasing energy prices and technological progress, renewable power generation has gained in importance. Renewable energy sources have proved to be a reasonable alternative to fossil fuels. Especially in rural areas with scattered settlements it can be cost-intensive to meet the demand for energy in a reliable way. Hence, stand-alone hybrid energy systems have become very popular. This master thesis analyzes and compares optimisation techniques for the optimal design of a hybrid energy system. For this purpose three papers are examined and compared with respect to efficiency and speed. The discussed papers feature an iterative method, quadratic programming and dynamic programming. As a result of the comparison, parameters for choosing the best possible optimisation technique are presented.