One of the measures introduced by the Energy Liberalisation Act in July 2000 (Electricity Act 2000) is the obligation to purchase green power and to reach minimum “eco-targets.” Distribution system operators are required to purchase electricity from recognised eco-plants up to a certain share of their electricity sales to final consumers (shares are to be at least 1% in 2001; 2% in 2003; 3% in 2005 and 4% in 2007). Purchase prices are regulated. The grid operators can resell these amounts of electricity to final consumers or to electricity traders. If the minimum percentage amount is exceeded, the grid operator can sell the excess amount to other operators of distribution grids. Qualifying eco-plants include wind, PV, geothermal, biomass, biogas, digester and sewage gas, as well as co-firing and multi-fuelled plants using a high proportion of biofuels, and combustion of wastes containing a high percentage of bio materials. The final decision on qualification is made by the provincial governments. The eco-electricity market is monitored by Elektrizitats-Control GmbH. An equalisation levy is imposed on the grid operators unable to prove the required share of eco-electricity.