6th Framework Programme
Case Study 1: Wittkiel

Case Study 1: Wittkiel

The biogas plant located in the very north of Germany in Stöltebüll is a typical agricultural biogas plant with only a singular input substrate of maize. This kind of mono input is very popular with farmers, who anyway produce feed crops for pigs and cows. Producing additional crops for energetic utilization is thus profitable, if farm land is available. The farmers see that maize production for biogas plant is a profitable business and also an ecological solution for producing electricity and heat. Mono input makes the production of biogas very reliable and continuous. There is no need for a refined composition of input. Thus there are fewer technical problems than in a plant with co-fermentation. Here in Wittkiel, at first, neighbors were afraid of smell and noise. When the plant started operation, they experienced that the smell was not a problem, even with the open residue storage. And the gas motor cannot be heard from more than 100 meters away. Due to the good harvest, experiences shows that biogas plants with maize input have one of the highest output of methane per hectare and also the running cost are one of the lowest.

Key data

Type of plant: Agricultural
Location: Stoltebüll, Germany
Operator: Biokraft Stenneshöh GmbH & Co. KG
Constructor: Bioconstruct
Operation start: November 2006

Operation facts

Mode: 2 parallel fermenters, secondary fermenter
Temperature range: Mesophilic
Main fermenter: 2 x 2,217 m3
Secondary fermenter: 1 x 2,217 m3
Final storage tank: 1 x 3,400 m3
Feedstock: Maize silage
Annual amount: 10,800 tons
Use of gas: 1 CHP with 500 kW el
Tpye of CHP: GE Jenbacher

Energy production

Electrical output: 6,328,000 kWh el
  supply for 1,580 households
Thermal output: 6,328,00 kWh
  equals 632,800 l of heating oil
Use of thermal energy Heating of pig sheds
  pig shed
  holiday houses
  wood chip drying

Additional information

Special feature: Exclusive renewable raw material fermentation
  Dry fermentation
Investment: 2 million €
Contruction changes: Further CHP with 265 kW in 2007

Diagramm of plant