Type of CHP system: Anaerobic digestion

Plant owner: Hermann Jöchtl, a farmer, is sole owner of the plant. It is operated as a sideline business of its agricultural enterprise

Commissioned: 2000

Status of plant: Commercial

Contractor details:

CHP: Hochreiter, Man, 62 kW + 75 kW, gross efficiency 32, 8% + 33,5 %, net efficiency approx. 31%; SO2 removal by means of an air compressor with a capacity of approx. 30 l air/min

Power generation: Gas engine

CHP1: 6-cylinder industion engine, 62 kW

CHP2: 6-cylinder turbocharged engine with intercooling

At the end of this year enlargement to an installed capacity of 500 kW.

Main fuel: Biogas

Grass  (300 m3, moisture content of 90%), 600 m3 agricultural residues, 1700 m3 silage

Nominal capacities & efficiencies:

Gross electrical output: 0,132 MWe

Net electrical output: 0,09 MWe

Heat output: 0,24 MJ/s

Electrical efficiency, gross: 33,15 %

Electrical efficiency, net: 31 %

Overall efficiency, gross: 81 %

Power to heat ratio: 0,58

How is plant controlled: The plant is controlled by the biogas yield.

Heat backup: Back-up boiler for heat supply: Fröhling wood gasifier, 35 kWth

Heat usage: Heating only

Energy usage:

The annual electricity production amounts to 757,528 kWh (2002) , of which 60,448 kWh/a are for proper use (residential house, fermenter, hall for wood drying), the remaining 697.080 kWh are fed into the public grid. The annual heat production amounts to 1.300.000 kWh (2002) of which approx. 30.000 kWh are used for heating the residential house and farm buildings, 167.580 kWh for the heating of the fermenter, and the remaining amount is used for heating the hall for wood drying.

Fuel storage: The fuel storage has a size of 1500 m3

Plant description:

The biogas plant is owned by a farmer. It is a continuous fermenter system (fermenter 560 m3, second stage fermenter = storage 890 m3). The aim was to use crops for energy production as alternative to conventional crop growing and the use of set-aside areas of agricultural land.

Authorisation: ElWOG 1999

Digester capacity: 1450

Residence time: 180

Process temperature: mesophilic process, temperature: 38 °C

Annual gas production: 490171

Gas quality: 51% methan, heating value: 5,1 kWh/m3

wet fermentation, dry matter 8-10%, two-level process

Electricity sale info: The feed in rate in Austria is regulated by law and depends on the type of biomass used and on the size of the plant.

Data collected and quality assured by: Austrian Energy Agency.

Contact person: Elvira Lutter