I-001-FI-019-EN
mml
● ● ● Particularity : small-scale private district heating network that sells the heat it produces.
The wood energy Trail
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Saint George : a small wood chip-fired district heating Valorisation of forestry by-products
Information on the community
In 1993, Henri Berseth, a forester, decided to put the wood unsuitable for commerce resulting from pruning, coppicing and felling in local
• Altitude : 945 m, • Population : 730 inhabitants, • Forest : c. 760 hectares.
Photo AJENA
The storage hangar
Exterior view of the boiler house
Programme of the Jura Department
community-owned or private woodlands to good use. Before it can be burned, firewood takes a lot of handling, and a minimum of two years to dry out. For this reason, if forestry by-products can be ground on site, the burden of handling the wood is reduced and the drying time is reduced to only two to four months. This means the work carried out can be transformed into profits more efficiently. In keeping with this activity, Mr. Berseth decided to install a wood chip-fired boiler in his home and to commercialise the heat thus produced. A small-scale district heating network heats five buildings equipped with substations : the school, two private homes, the Berseth family home and the company premises. Other local people are taking a great interest in the undertaking and are waiting to be joined to the network, which is technically possible because the boiler was deliberately built oversized in order to accommodate further connections.
Mr. Berseth’s company provides the fuel to its customers. A hangar with a capacity of 500 m3 situated near the boiler room provides storage for fuel throughout the period during which heating is needed. The fuel is a mixture of broadleaf and resinous wood with a moisture content of between 30 and 40 % of the gross weight. After drying out for at least two months in the hangar, the fuel is delivered by means of a hopper of 6 m 3. This is the only solution possible given the situation of the two silo doors, underneath the roof, which prevent delivery by a tipper lorry (see photo below left, where the silo is visible to the left of the house). The wood chips are unloaded into a 50 m3 silo equipped with hydraulic scrapers to transfer the fuel to the boiler. In addition, to prevent the hydraulic rams from using too much electricity, a small intermediary silo of 1 m3 was installed. This means the scrapers only function for half an hour per day. The annual consumption in wood chips is estimated at 500 – 600 m 3 per year. The company also sells nearly 400 m3 of wood chips per year to other farmers with similar boilers. In this case, the fuel is delivered in a lorry with a capacity of 35 m3.
A self-operating boiler plant The HATA boiler has an output of 130 kW and its combustion system is an underfeeder screw. The system burns wood chips with a moisture content of up to 40 % of the gross weight. The boiler is equipped with an automatic ash-clearing system, which stores the ashes in a small container, which must be emptied once a week. The flues carrying smoke from the exchanger
© ITEBE- july 1999
Photo AJENA
Fuel supply
I-001-FI-019-EN
mml
1. 2. 3. 4. 5.
6. 7. 8. 9. 10. 11. 12.
Fuel storage silo Trapdoors giving access to the silo Hydraulic fuel extractor system Fuel transfer screw (See photo below) Transfer screw
Intermediary silo Fuel transfer screw Primary air ventilation Secondary air ventilation Combustion chamber Post-combustion chamber Heat exchanger
13. 14. 15. 16. 17.
are cleaned once every three weeks. The buildings supplied with heat all have their own substation with a small heat exchanger and calorie counter, to measure the number of kWh used by each building so that the bill for each can be easily calculated.
Information on financing Photo AJENA
• Total investment costs : - Equipment for the boiler room : 325,000 € Inc. Tax. - Equipment for the heating network : 105,000 € Inc. Tax. • Financial partnership : 49,450 € contributed towards the investment from the Helvetian Confederacy and Vaud Region.
Programme of the Jura Department
ITEBE - European Technical Institute for Wood Energy 28, boulevard Gambetta - BP 149 F-39004 Lons-le-Saunier Cedex Tel.+33 (0)3 84 47 81 00-Fax.+33 (0)3 84 47 81 19 E-mail: info@itebe.org - Web: www.itebe.org
HATA (boiler manufacturer) Heideweg 35 CH-2503 Biel Tel. +41 (0)32 351 45 45 Fax. +41 (0)32 351 44 58
For visits, contact : Entreprise forestière Henri Berseth CH-1261 Saint George Tel. +41 (0)22 368 12 42
Interior view of the boiler room Steiermark
Information
Forest and Wild Life Administration Carolline 11 bis - CH-1014 Lausanne Tel. +41 (0)21 316 61 61 - Fax. +41 (0)21 316 61 62
Photo AJENA
This factsheet was designed by AJENA and ASEB as part of the Altener wood energy programme, financed by the European Union (DG XVII), the Jura Department (programme contractor), ADEME (the French energy agency), AJENA (Jura association for the promotion of renewable energies), ASEB (Swiss association for wood energy), and the Styrian Chamber of Agriculture (Austria).
Point of departure for the heating network Chimney Worm screw for ash clearing Ash container System controls cupboard
ASEB (Swiss association for wood energy) En Budron H6, CH-1052 Le Mont-sur-Lausanne Tel. +41(0)21 653 07 77 - Fax. +41 (0)21 653 07 78 E-mail : info@aseb.ch - Web : www.aseb.ch
• Contractor : Entreprise forestière Henri Berseth
Fuel transfer screw
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To receive copies of the other factsheets in this series, contact : (see address above)
Editions
Lons-le-Saunier - France
Installation diagram
The wood energy Trail
© ITEBE - July 1999. Design : AJENA. Printed on 100 % recycled paper at
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