French Landfill is Using Remains of the Past to Illuminate the Future
GE – The giant Plessis-Gassot 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 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 as a result.
France plans to generate 23 percent of its energy from renewable energy sources by 2020. They include solar and wind power, but also biomass and landfill gas.
The gas is produced when anaerobic bacteria decompose organic waste in an airless environment, like deep inside a compact mountain of trash. Landfill gas contains mostly energy-rich methane mixed with impurities like carbon dioxide and nitrogen. It is similar in composition to natural gas, but dirtier.
The Plessis-Gassot power plant is using 10 advanced Jenbacher gas engines to produce the heat and electricity. Using landfill gas to make electricity is not a new idea, but the engines, which are manufactured by GE in Austria, can be up to 42 percent efficient in converting gas to power. (The system total efficiency including heat is 85 percent.) They replace an older boiler system that was 22 percent efficient. more> http://tinyurl.com/ovwjfwp