First Commercial Heat and Power Plant in Switzerland Based on Wood Gasification

First Commercial Heat and Power Plant in Switzerland Based on Wood Gasification
Dasagren/Netpro, March 2007
Wila 450 kWe

The First Commercial Wood Gasification Heat and Power Plant in Switzerland Powered by an Indo-Swiss Gasifier

CO2 Neutral Technology Ready for Large Scale Application in Europe

More detail from the Netpro web site:

It was a great day for Victor Bosshard, the President of WoodPower AG, Wila and his two sons who took charge of his 350 kWe power plant last week after its commissioning and test run by Dasag Renewable Energy AG (Dasagren) from Switzerland , the engineers and suppliers of the gasification Island. The 425 kg/h gasifier and the gas cooling system have been designed and manufactured by Netpro Ltd., Bangalore, India and the total system has been adapted for Swiss conditions, engineered, supplied, erected and commissioned by Dasagren. The gasifier delivers producer gas containing hydrogen and carbon monoxide as the main fuels to a GE- Jenbacher engine from Austria. The engine and waste heat systems, which have also been commissioned and taken over by WoodPower, deliver 350 kW to the electric grid, and supply waste heat for drying wood chips for household boilers and hot water for heating and domestic use to Mr. Bosshard’s farmhouse.

The combination of a proven low tar gasification process, using sustainable sources of wood from local forests and waste wood from local sources, and a modern gas engine generating electricity and process heat in a co-generation mode, establishes power plants which deliver CO2 neutral energy at very high efficiencies. These create local jobs and increase national energy self-sufficiency. With the increasing precariousness of the energy situation and worries about climate change, it is not surprising that the demand for green power is very high from Swiss electricity consumers. The progressive local cantonal power utility, EKZ, which already runs a solar electricity exchange market, decided to co-invest in WoodPower and signed a long term power purchase agreement at a renewable energy based tariff. The total investment of CHF 4.4 million (approx. 2.75 million Euros or 1.9 million Pounds Sterling) is expected to be amortised within seven years with the expected revenues from the sale of electricity and waste heat. In fact, the successful adaptation of the gasifier to produce high quality gas from very low cost waste wood makes such co-generation power plants a very attractive solution for decentralised applications at the level of communities and farmer’s co-operatives. The economics of these plants are likely to increase even further when a CO2 levy is introduced in Switzerland.

More than twenty biomass gasification based power plants running in India have been built by Netpro. While India leads the world in successfully operating the largest number of biomass gasification power plants, the Indian technology can not be used as it is in Europe and needs adaptation to take into account the local conditions. Some of the requirements are:

  • Optimising the wood processing and management systems.
  • Adapting the design and fabrication to the European certification and quality norms.
  • Adapting the design for ease of shipment and the reduction of the erection time.
  • Drastic reduction in the manpower requirements by optimising plant engineering, designing for low maintenance and incorporating a high degree of automation.
  • A water treatment system to meet the effluent norms.
  • A waste heat management system to increase profitability.
  • Exhaust gas conditioning to meet air quality norms.

The process of testing and adaptation of the Indian technology was started as early as in 1994 and the power plant in Wila is a further example of the on-going Indo-Swiss co-operation program. An 80 kg/h test gasifier supplied by Netpro was installed in Chatel-St-Denis, near Lausanne, with the financial support of the Swiss government to test and adapt the very advanced biomass gasification process. Tests with various types of Swiss wood were successfully completed and subsequently a 55 kW gas engine was installed and operated for over 500 hours. The test installation was also used to measure the exhaust gas emissions from the engine and test the gasifier effluents for contaminants. It was concluded that all Swiss environmental norms could be met by such a power plant.

Dasagren, a company formed three years ago specifically for re-engineering the Indian Netpro system and supplying wood gasification power plants in Europe, worked closely with Netpro and WoodPower to commission the plant within 12 months. The gasifier and the gas cooling-cleaning chain were shipped from India in containers and the erection was done very largely by the customer with the help of local companies. Significant changes have been made in Switzerland to ensure trouble free operation with waste wood which behaves very differently from normal wood pieces. The plant operates automatically though at present some manual intervention is still needed in the wood feeding and the ash handling systems.