New lean gas record levels!

Aug 20, 2019

Methane is extremely damaging to the climate: The Intergovernmental Panel on Climate Change (IPCC) has stated in its 5th Assessment Report AR5 that, within an observation period of 20 years, methane has an 84 times higher global warming potential (GWP) compared to CO2. Methane or methane-containing gases must therefore be flared, unless they are used advantageously in combined heat and power plants for heat and power generation. As part of the FFG funded project “CHPs for weak and problem gases” we (under the patronage of Bioenergy 2020+) have recently shown, that CHPs with Frauscher alphagamma® Stirling engines  still maintain stable operation and high efficiency at a methane content of 14%.

For example, lean gases are produced in landfills in the second phase of degassing or as a slip gas in biomethane production. As a result of admixing raw gas, lean gases can be disposed with much lower methane content. The result is particularly record-breaking if we consider the excellent emission values. With a residual oxygen content of 5.0%, only 29.9 mg/mn³ NOX and 149.2 mg/mn³ CO could be measured. The total electrical efficiency of 31% (for natural gas) only drops to 26%. “This is a result that we have achieved without any particular effort. We will get to a methane concentration of about 10% after some adjustments. The practical suitability under the given conditions are going to be investigated in field trials shortly.” Josef Frauscher, managing director of the Company.