Abstract The increase of intermittent electricity generation from renewable energy sources (RES) requires more flexibility from the demand side. Different applications and processes exist, which can provide Demand Response (DR) potential by shifting or shedding their load. The availability of most applications depend on the ambient temperature and/or time of day. Furthermore, their commitment is limited by technical restrictions, e.g. shifting time. In this paper, the availability and the flexibility of DR is analysed to investigate its role for the system integration of RES in Germany. In a first step, DR potential on an hourly basis is calculated for today and for future years. In a second step, the use of DR in an electricity system with different RES shares is investigated with an electricity market model. Results show, DR reduces RES curtailment. However, due to its limited availability and flexibility, it cannot integrate high amount of RES surplus over a longer period. Instead, it balances short-term fluctuation of the residual load curve. The exploited potential varies between DR applications because of their different characteristics. Therefore, focused (on selected applications) rather than broad development of DR potential is needed to shape the future energy system in a cost efficient way.