Cow power

A German city has become the first in the world to start work on a biogas network to produce local power from cow dung.

The network, which has been described as “a model for the future of local power generation” is currently being built in Lünen, North Rhine–Westphalia. It is hoped that when work is completed in December 2009, the city will be able to produce cheap and secure heat and electricity for 90,000 residents, thus reducing local reliance on fossil fuels.

Once the network is operational, farmers will deliver animal slurry and spoiled crops to the city’s anaerobic digestion plant, which is capable of producing 6.8MW of energy – 30-40% of the city’s needs and enough to supply 26,000 houses with heat and electricity.

The gas will be distributed over the city through a new underground biogas pipeline network, which is being built using a horizontal drilling robot to minimise road disruption. It will then be burned in a series of 12 combined heat and power (CHP) units, which will feed electricity into the grid, and heat into local district heating networks.

Peter Kindt, the chairman of CHP distributor Alfagy, said that biogas plants are “quiet, efficient and reliable” and are therefore “barely noticeable” to residents, unlike wind or solar power.

Other cities worldwide are now considering similar projects.