23 February 2010 – The world’s first solid oxide fuel cell (SOFC) unit running on landfill gas has successfully concluded the first phase of its validation programme.
The WFC20, which is developed and operated by Wärtsilä, is the first of its kind in the world. The power generating unit has been operating for more than 1500 hours producing low-emission power to households in Vaasa, Finland.
The unit is run on methane rich gas, originating from a nearby landfill. Methane is a strong greenhouse gas that would otherwise be harmful to the environment. The WFC20 is based on planar SOFC technology, which is supplied by the Danish company Topsoe Fuel Cell.
The main project targets set by Wärtsilä for this groundbreaking power generation unit have all been achieved. The demonstrated energy efficiency has reached very high levels, exhaust gas emissions are extremely low, and the unit has been able to operate consistently despite the biogas having low and fluctuating methane content.
The fuel cell unit produces an electric output of approximately 20 kW, which is enough to power approximately 10 households in the area. The thermal output of the unit ranges from 14 to 17 kW. The exhaust gas emissions from WFC20 are measured as being extremely low.
The varying composition of the methane rich gas from the landfill has been one of the main engineering challenges for the test site, and it has led to the development of an efficient control system. The functionality of the system has been fully validated. Landfill gas contains also a number of impurities, such as sulphur compounds, which need to be removed from the fuel before being fed to the fuel cell system. This has also been successfully achieved.
The fuel cell unit does not produce any measurable levels of harmful particles, sulphur oxide (SOx), or nitrogen oxide (NOx) emissions, even at part load conditions. When using bio gas as fuel, the emissions of CO2 are very close to carbon neutral.