Biogas Flows Through Germany's Grid Big Time

The plant at Konnern will feed 15 million cubic meters (m³) of biomethane into the national grid for use by customers anywhere in Germany. Experts say it is the start of a boom in biogas as the country's energy providers increasingly look to home-produced biogas to reduce their dependence on natural gas imported from Russia.

In 2007, there were 1280 megawatts (MW) of installed biogas capacity and about 3,750 biogas plants in Germany.

As much as 20 percent of Germany's natural gas needs could be supplied from biogas by 2020, according to Andrea Horbelt of the German Biogas Association.

Horbelt said that some studies predicted that Germany could even supply its entire natural gas needs using biogas if it were able to tap the agriculture potential of Eastern Europe with sufficient efficiency. But for now the focus is on exploiting the potential in Germany where a well-developed national grid facilitates biogas transport.

"Biogas is the market of the future because it allows energy to be produced and transported economically and in a decentralized way around the country," said Pivi Scamperle of agri.capital, the company that runs Germany's largest existing EU €10 million biogas plant, feeding 6 million m³ of biomethane into the national grid.

The boom in biogas comes thanks to a key technological breakthrough a year ago that allowed biogas to be injected into the natural gas grid and so transported around Germany economically, said Thomas Wilkens of WELtec BioPower, a company that manufactures biogas units.

Until that breakthrough, as much as two-thirds of all the energy produced by combined heat and power biogas plants couldn't be used because there was not enough demand for heat at the point of generation — usually in agricultural areas — and there was no technology available either to put the gas into a pipeline and bring it to customers in other places.

"Biogas from Konnern will go all around Germany through the national grid," Wilkens said. "There is a growing demand for plants like this because energy providers are eager to find a way of reducing Germany's dependence on expensive gas from Russia. Biogas could make a big contribution to energy self-sufficiency as well as to fighting global warming."

However, he said that the new technology was just one piece of the puzzle. The biogas plants also have to be located in areas where there are big enough farms to guarantee the raw materials needed to keep the plants running.

Thirty farmers in the vicinity of Konnern will deliver 120,000 tonnes of raw materials each year, mainly corn crops. The eight fermenting tanks are expected to produce 30 million m³ of biogas per year, which will be processed into 15 million m³ of biomethane.

"The biogas won't be burned to produce electricity but will be put instead through a special process of chemical washing without pressure so that it ends up having the same composition as natural gas and so can be injected into the same pipelines as carry the natural gas," Wilkens told RenewableEnergyWorld.com.

Biogas contains about 60 percent methane and 40 percent carbon dioxide while natural gas contains about 97 percent methane. The technology at Konnern involves filtering out the carbon dioxide to increase the proportion of methane in the biogas. At the end of the process, the biogas is 99 percent biomethane.

WELtec BioPower, which has 55 employees, has built about 200 biogas plants around the world, with 150 of these in Germany and the company expects many more orders over and above Konnern as the sector takes off again following some industry setbacks.

Andrea Horbelt said the new grid technology and new tariffs would lead to expansion in the biogas sector after a severe slump last year caused by the doubling in the price of corn and wheat in the past 16 months.

"Germany's four big energy providers have recognized the value of biogas and we think there will be a bright future for large-scale biogas plants that feed gas into the national grid," Horbelt said.

Small-scale biogas plants that use liquid manure as a raw material have also been given a boost by a revised renewable energy law that cleared its last parliamentary hurdle on July 4, 2008. Biogas plants of 150 KW that use liquid manure will get EU €0.04 per kilowatt-hour (kWh), making them more attractive. By setting a generous tariff for manure, the government is hoping to encourage the biogas industry to switch away from corn and wheat amid concerns of rising food prices.

"Research is just beginning to look at the many types of plants that could be used to produce biogas," said Horbelt. "We are confident there will be many alternatives to using crops such as corn."

With the price of natural gas in Europe set to double in the next year according to some economists, Europeans will be hoping the biogas boom lasts.

The Konnern biogas plant is almost as big as the Huckabay Ridge Renewable Natural Gas facility in Stephenville, Texas, where 635,000 MMBtu of biomethane generated from cow manure and other organic waste has been injected into the Enterprise natural gas pipeline since January 2008, making it the world's biggest.

Jane Burgermeiser is a writer based in Austria.