Type of CHP system: Grate fired boiler

Plant owner: AB Enköpings Värmeverk which in turn is owned by Enköping municipality.

Commissioned: 1994

Status of plant: Commercial

Contractor details:

Main contractor: Owner.

Boiler: Burmeister & Wain Energi A/S.

Turbine: ABB, Wood handling: BMH, Electrical Emil Lundgren

Power generation: Steam turbine

Traditional flue gas condenser without moisture injection in airflow

Main fuel: 100% biomass, forest residual

Nominal capacities & efficiencies:

Thermal input, biomass & waste: 80 MW

Total thermal input, incl. fossil fuels: 80 MW

Gross electrical output: 24 MWe

Net electrical output: 22,5 MWe

Heat output: 55 MJ/s

Electrical efficiency, gross: 30 %

Electrical efficiency, net: 28 %

Overall efficiency, gross: 99 %

Input 80 MW fuel; output 24 MW gross el; 22,5 net el; 45 MW heat condenser;10 MW flue gas condenser

How is plant controlled: Controlled by heat demand and accumulator on heat

Heat backup: Wood powder district heat boiler on 20 MW

Heat usage: Heating only

Energy usage:

Private households and industry in Enköping. Electricity to the Nordpool market

District heat coverage (% of total demand in DH network): 95 %

DH inlet temperature: 75-100 °C

DH return temperature: 40-55°C

Heat storage size: 7000 m3

Hours of full load that the heat storage can meet: 5

Fuel storage: 8000m3

Waste water: 0-10m3/s. To waste water treatment plant owned by municipality.

Ash discharge: Bottom ash as fertilise to Salix fields. Fly ash to waste disposal area

Plant description: Traditional CHP. Steam cycles: 100 bar, 540 degress Celcius, 108 tons per hour.  Vibrating grate, VAX turbine (Power to heat ratio: 0,57) The fuel is forrest residuals

Fuel feeding system:

Incoming fuel chipped <5mm. Chain feeder from tipping pocket to rubber belt. Mechanical riddle, scrape feeder to storage under roof 8000m3. Rubber belts up to boiler storage 50 m3. Screw feeding in four pallell to boiler. Spreader stoker into boiler. Boiler: Drum boiler single overheat, 92% efficiency acc to DIN 1942,Natural circulation

Turbine: 2Axial turbines, HP 13200rpm, LP 6500 rpm, Generator 1500 rpm

Steam data: 100 bar, 540 degree Celcius, 108 tons/hr

Flue gas cleaning: SNCR, Elctrostatic precipitator, Flue gas condenser if electric price is below 350 SEK/MWh

Cooling system: No cooling system external. Only internal used for heating the building

100 bar, 540 deg C 108 tons/hr, Avalibility 99%

Staff: Full time employees 36, At daytime 2 persons operate the plant. At night 2 persons operate the plant

Electricity sale info: Nordpool+elcert, Varying every hour

Total capital cost: € 30,000,000

Year 1994

Boiler € 10 million,Turbine € 7 million, Fuel Handling € 3 million, Builldings € 3 million, Instr control € 2 million

Data collected and quality assured by: Swedish Biomass Association.

Contact person: Johan Vinterbäck