Landfill fuels France’s energy future

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GE-2
GE
Courtesy of GE

Landfill fuels France’s energy future

Sponsor generated content

GE-2

When the giant Plessis-Gassot landfill opened its gates outside of Paris in the 1960s, Charles de Gaulle was France’s president.

Since then, the landfill has gobbled up millions of tons of refuse thrown out by generations of Parisians. That trash is now playing a bright role in France’s renewable energy future. It supplies the country’s largest landfill power plant with enough methane-rich biogas, also called landfill gas, to generate electricity for more than 40,000 French homes.

The plant, which opened in June, also gives off enough heat to make the nearby town of Plessis-Gassot the first French municipality with a district heating system fueled by landfill gas. The town hall, church, community hall, and residences connected to its heat pipes could see their heating bills fall by a whopping 92 percent.

The Plessis-Gassot plant’s ability to replace electricity generated by conventional fossil fuels has earned a 15-year contract to sell power back to the grid at a rate exceeding €0.10 ($0.14) per kilowatt hour. “It’s a great business model,” says Didier Lartigue, managing director of Clarke Energy in France, which built the plant for the energy and waste management company Veolia. “The gas is basically free, and when we recover the heat from the process, it’s an additional bonus.”

France is tackling the question, “What would happen if energy could come from anything, or go anywhere?” The country plans to generate 23 percent of its energy from renewable energy sources by 2020. These renewable sources include solar and wind power, in addition to biomass and landfill gas.

Landfill gas is produced when anaerobic bacteria decompose organic waste in an airless environment, like deep inside a compact mountain of trash. The gas contains mostly energy rich methane mixed with impurities like carbon dioxide and nitrogen. It is similar in composition to natural gas, but dirtier.

Using landfill gas to make electricity is not a new idea. However, the Jenbacher engines used in the Plessis-Gassot power plant, which are manufactured by GE in Austria, are 20 percent more efficient in converting gas to power than the plant’s older boiler system. The system’s total efficiency in gas to power conversion, including the heat it produces, is 85 percent.

There are 10 advanced Jenbacher gas engines used in the Plessis-Gassot power plant. The engines’ sturdy design allows them to gobble up biogas generated from pretty much anything, including cheese whey, whiskey mash, and discarded school lunches.

The Jenbacher engines, which are part of GE’s “ecomagination” program, belong to the company’s new distributed power business. Distributed power technology allows customers to generate their own power near the point of use, rather than relying on a centralized grid that can be miles away. The concept is taking hold with the developing world and with industrial dynamos like France.

Imagination is taking energy to new places. “Power generation is shifting from a centralized to a decentralized model,” says Wouter-Jan van der Wurff, a GE gas engine product line leader. “We have the capability to supply engines for power generation to maximize fuel efficiency where customers need it.”