Type of CHP system: CFB boiler

Plant owner:

Owned by Jämtkraft AB, which is owned by Östersund Municipality (around 78%), Krokom Municipality (around 0,8%), Åre Municipality (around 0,8%) and Vattenfall (around 20%)

Commissioned: 2002

Status of plant: Commercial

Contractor details: Foster Wheeler (boiler, buildings), Siemens (turbine)

Power generation: Steam turbine

Flue gas condenser, 30 MW. Delivered by SENEA Miljöteknik

Main fuel:

Multifuel (more biofuels and/or peat)

Bark 30% (moist 55%), Sawdust 25% (moist 50%) ,Forest residual 25% (moist 45%), Peat 20% (moist 45%). Annual consumption biomass 460 GWh, Peat 115 GWh.

Nominal capacities & efficiencies:

Thermal input, biomass & waste: 137 MW

Total thermal input, incl. fossil fuels: 137 MW

Gross electrical output: 45,3 MWe

Net electrical output: 41,8 MWe

Heat output: 110 MJ/s

Electrical efficiency, gross: 33 %

Electrical efficiency, net: 30,5 %

Overall efficiency, gross: 113 %

Heat capacity 80 MW. Flue gas condensor 30 MW.

How is plant controlled: By heat demand

Heat backup: 3×25 MW biomass fired boilers, with flue gas condenser. 4×25 MW oil boilers. Heat pump 10 MW. Electric boiler 10 MW. Landfill gas boiler 2 MW. Biogas boiler 1 MW.

Heat usage: Heating only

Energy usage:

The boiler is connected to the city of Östersund district heating system. Energy delivered to the district heating system is 523 000 MWh/year. 2900 customers. (Approx 25 000 households and some industries.)

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

DH inlet temperature: 70-100 °C

DH return temperature: 45-55°C

Heat storage size: A new accumulator on 26000 m3 that was erected in september -04.

Hours of full load that the heat storage can meet: 10 hours at full load winter time, 3 days during summer time.

Fuel storage: Maximum allowed storage is approx. 100 000 MWh. Approx 35 days of full load operation.

Waste water: From flue gas condensor, pH-adjustment and sandfilter.

Ash discharge: Deposition, landfill

Plant description:

Jämtkraft district heating grid in Östersund is today 180 kilometer.

The new combined heat and power plant is built next to the already existing district heating plant, which has two boilers that together produce 50 MW of district heat. The combined heat and power plant is now in operation and the old plant will

become a stand-by facility, which will only be operated in summer when

the CHP plant is closed. The existing plant will also be used as a peak load facility when the

outside temperature falls below minus 10 degrees Celsius, which is quite usual in county of

Jämtland in winter.

Fuel feeding system:

Different kinds of fuel is carried by a tractor to a 2000 m3 storage in the ground  outside (no roof). From the storage:  screw, belt conveyer, screen, magnet, 2 belt conveyers, 2×150 m3 silos, 2 scrape conveyers, 2 screws, 4 cell feeders, 4 screws

Boiler: Foster Wheeler. Circulating fluid bed (CFB)

Turbine: Siemens TRLI 80/27  ,  2-pol, 3000 rpm. 10,5 kV

Steam data: 144 bar, 545 degree Celcius, 184 tons/hr

Flue gas cleaning: Elctrostatic precipitator, NOx reduction by grind catalyzer SNCR, flue gas condenser

Cooling system: Water from the lake Storsjön

Staff:

Daytime:5 persons +1 fuel handling + 2 drivers of tractor which load and unload fuel. Maintaince: 2 electrians +3 mechanics.                                                       Night and weekends: 3 persons

Electricity sale info: Follows Nordpool spotprice (hour).

Total capital cost: € 60,000,000

Boiler 32 million Turbine+generator 11 million

Data collected and quality assured by: Swedish Biomass Association.

Contact person: Johan Vinterbäck