Germany's Nawaro Bioenergie builds world's largest biogas complex: 20 MW

German bioenergy company Nawaro Bioenergie AG is completing the world's largest integrated biogas power station in Klarsee, Penkun, in the German state of Mecklenburg-Western Pomerania.

The complex will generate 20 megawatts of electricity by fermenting energy maize by liquid manure. After fermentation the biomethane is converted by combustion into electricity and heat. The complex utilises 40 Jenbacher Gas Engines that will cogenerate 20 megawatts of electricity and 22 megawatts in thermal output. The 40 units were delivered by EnviTec which specialises in the standardisation of 500kW modules. The first module began operations in November 2006 and by now 15 modules are operating. The 20MW output is enough to meet the energy needs of a town of 50,000 people. The electricity generated at NAWARO is fed into the power grid, as agreed by utilities.

The Klarsee complex is located close to the German-Polish border, where around 50 to 60 agricultural enterprises and farmers from both countries deliver the feedstock. Approximately 300,000 tonnes of specially bred maize silage, 60,000 tonnes of manure and 20,000 tonnes of grain per year are required. Silage maize is particularly well suited as a renewable fuel for biogas as it contains more energy than most other feedstocks. Per hectare, conversion into biogas shows around twice the yields of conversion into liquid biofuels.

The carbon-neutral and self-contained cycle of raw material and energy is also a worldwide first: nearly all the fermentation residues produced are converted into high-quality depot fertiliser to be sold on the international market (schematic, click to enlarge). The vicinity of the Baltic Sea ports represents a reloading point for shipping out the fertilisers. This brings in an additional €50-150 per tonne of feedstock. All that is left after a processing cycle is clear water, making the power station’s total efficiency and environmental performance superior to that of conventional farm-based biogas plants.

Biogas is the least carbon-intensive of all renewable energies (previous post). In the long-term, the production of the biomethane can be integrated in carbon capture and storage (CCS) concepts, which would result in carbon-negative energy systems. Only bioenergy-based energy systems can acquire this status, and could thus radically help reducing global carbon dioxide emissions. Biogas is particularly interesting in this respect, because it offers the potential for low-cost carbon capture, by separating CO2 efficiently before the combustion of the gas (earlier post).

Behind the industrial-scale project in Klarsee stands the vision - now prevalent throughout Germany - that electricity from biogas can play an integral part of the energy market worldwide. Some projections show that the potential is so large that the EU could replace all natural gas imports from Russia with biogas, by 2020 (previous post). Upgraded and cleaned, biomethane can be fed into the existing natural gas infrastructure. Several projects in Germany are already doing this, and a large EU-funded study on feeding biomethane into NG pipelines is analysing the issue in-depth:
energy :: sustainability :: biomass :: bioenergy :: biofuels :: maize :: manure :: anaerobic digestion :: biogas :: biomethane :: cogeneration :: Germany ::

The vision is backed up by numbers: German biogas units produced 2.9 billion kilowatt-hours of electricity in 2005, or about three times as much electricity as the amount supplied by photovoltaic solar cells. The new plant promises to push biomass energy to new levels - using all of its standardized modules it will generate electricity with a total capacity of 20 megawatt. NAWARO has two other biogas parks of the same size are under development.

NAWARO’s financing is done by Doric Asset Finance, which set up the Geno Bioenergie 1 fund of around €100m for the Klarsee biogas park. Minimum investment was €10,000; the first distribution for investors is projected for November 2008 at 5.5% of the contribution, with further 9% payments per year from 2009 onwards.

Biogas is the fastest growing renewable energy sector in Europe, with electricity generated from biogas growing much more rapidly than the overall biomass, wind and solar sector in recent years. More than 2,500MW have been installed to date in Europe. Germany leads the field in electricity generation from biogas, with about 3,500 installed plants and a combined capacity of 1,100 MW. The German Biogas Association estimates that this capacity could grow up to 9,500MW by the year 2020.

Besides the potential to feed the green gas into the natural gas grid, it can also be used as a transport fuel in CNG vehicles.

Compiled from sources found at Nawaro Bioenergy, AG.

References:
Nawaro Bioenergie AG, website.