Biogas is a renewable and increasingly important energy source created from biological matter and harvested from sewerage systems and landfill sites.
Capturing the natural gas emited from the breakdown of the organic material keeps the gas from the local environment and provides a potent source of energy.
Microgeneration of biogas on farms and in industrial plants provides a good opportunity to better use energy in small local plants.
Christchurch is a leader in the field of capturing methane for power generation using both Burwood landfill and the Bromley Wastewater treatment plant. Pre-earthquakes gas from Burwood landfill was piped underground to the QE II swimming pool and sports complex. There it was used to heat the pools and power the facilities. Around 60% of the gas emitted at Burwood is methane. Methane has a global warming potential of 22, compared to carbon dioxide which has a rating of 1, meaning methane is one of the most damaging greenhouse gases routinely emitted in our cities.
The same energy was used to heat and cool the Christchurch Art Gallery and the Civic Offices. There is intended to continue as Christchurch rebuilds.