Heating with wood chips: the farmer as an energy service provider, Nestelbach - Austria

Heating is comfortable and cheap for the residents of 4 blocks in the village of Nestelbach, in the Austrian Province of Styria. The 19 flats are heated with wood chips. 3 farmers invested in the heating system, they operate and maintain the system and supply the woodchips. The product they sell is a high quality heat service.

Operation and maintenance of the wood boiler

• The 100 kW KWB woodchip boiler has an efficiency of 91% and CO emissions of 90mg/m3, which is about 0,5 % of the emissions of an old logwood boiler. It includes automatic cleaning of heat exchanger surfaces, microprocessor control and automatic alarm via mobile phone in case of a problem.
• Wood chips are delivered once a month with the tractor
• The boiler is inspected twice a week
• Ashes have to be removed twice a month ( two buckets each time) and are used as fertiliser
• 3 bearings have to be greased twice during the heating season
• The chimney sweep comes every month and cleans the boiler with a vacuum cleaner
• Boiler service by the manufacturer once a year (part of a service contract)

Advantages of the model

• Subsidies available for farmers investing in wood heating plant
• No need to invest for developer
• No need to organise maintenance for developer
• Cheaper heating for residents than with conventional fuels
• Long term security of supply and price stability
• Supports rural economic development

Wood chips versus pellets

• Wood chips are cheaper than pellets and can be produced locally
• Besides needing more storage space they can also be an excellent fuel, however
• Quality control of wood chips is very important
• Wet chips or large wood pieces in the chips cause operation problems
• If the wood chip supplier operates the plant (as in the presented case) he quickly learns to takes care of good fuel quality

What about operation failures?

• A reliable boiler is very important – look for experienced manufacturers (high quality boilers)
• Automatic alarm of operator via SMS on his mobile phone
• So far hardly any failures (1-2 times per heating season)
• Problems could be fixed in 5 minutes

Technical Data:

• Heat load: 100 kW
• Heat demand: 140.000 kWh
• Wood Chip demand: 260 m³ (spruce)
• Wood Chip Storage: 50 m³

Economic Data:

• Investment costs:
• Boiler and fuel feeding: 17.500 €
• Storage construction: 22.000 €
• Installation costs: 4.400 €
• Total: 43.900 €
• Investment subsidy: 40%
  
• Heat tariffs:
• Investment contribution: 254€/kW
• Basic price: 14,5€/year and kW
• Measurement price: 18 €/flat and month
• Heat price: 47 €/MWh

The person behind the success:

Herbert Lammer, Consultant, Regionalenergie Steiermark: “Our organisation was established by the Styrian Association of Wood owners, to help farmers to set up small energy service businesses. We identify possible projects and help interested farmers to realise a project from the first idea all the way through establishing the necessary contracts, establishing the heating plant up to routine operation. Since 1995 we helped to realise over 70 such projects and interest is quickly growing.”