Table 1 Empirical study: overview of case studies

Area, inhabitants

112 km², 51,292 (12/2009)

203 km², 21,856 (06/2008)

Grid operator(s)

1. Public utility (Stadtwerke Emden);

2. Public port authority (N-Ports); and

3. Private regional utility (EWE NETZ)

Only public utility (Stadtwerke Soltau)

Centralized electricity generation

1 Gas power plant and 1 biomass power plant (wood leftovers)

16 Wind turbines

Decentralized electricity generation

(installed capacity)

75 Wind turbines (approximately 143 MW installed/approved); 120 photovoltaic facilities (approximately 1 MW); 1 sewer-gas plant

Produce, together with central biomass plant, is ca. 100% of electricity consumption in Emden

11 Biogas plants (approximately 10 MW); fossil combined heat and power plant; photovoltaic facilities

Produce is 85% of consumed power in grid area of which 68% are from biogas plants

Origin/pioneers

Long tradition:

• Erection of first wind turbine for pumping water in the 1980s

• City passed formal regulation relatively early (ROP, FNP 1994) and commissions public utility with installing first turbine

Initiative of agricultural actors in the mid-1990s:

• Formation of a biogas working group

• Erection of first plants close to farms