An energy-saving target agreement with the Swiss Federal Government, a share of more than 5% electricity costs per gross value added, and a refund amount of at least CHF 20'000 per year: Under these conditions, large commercial or industrial end users are entitled to a refund of their national network supplement for the promotion of renewable energies. How do modifications to the supplement and to the refund requirements affect the refund claims? A study by INFRAS and TEP Energy on behalf of the Swiss Federal Office of Energy SFOE shows that they mainly affect the number of eligible companies. Despite that, the analysed modifications have little influence on the share of the refund claims of the entire supplement levied.