4Biomass - Fostering the Sustainable Usage of Renewable Energy Sources in Central Europe Putting Biomass into Action!

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2 Aim of the Study Tour In the Application form the partners of 4biomass stated that one of the main objective of the project is to foster the sustainable exploitation of biomass by exchanging experiences and best practices between the partners and other stakeholders. Through this an equal level of knowledge regarding available technologies, investment possibilities and operation of bioenergy system can be reached. Through the joint Study Tour to first Austria and secondly to Hungary, the project partners had the opportunity to visit different plants as described in more detail below. Location Güssing, European Centre for Renewable Energy Address: Municipality Güssing, Burgenland web: About the EEE The European Centre for Renewable Energy (Germ. abbr. EEE), headquartered in Güssing (southern Burgenland), was founded in With its employees, currently 14 in number, the EEE develops lasting regional and community-based concepts for energy conservation and for the generation and use of renewable energy. Güssing as a Model for regional Economic Improvement The so-called Güssing Model is the strategy of de-centralised, local energy production with all locally available renewable resources in a region. This model came into being so to speak out of necessity and is the quintessence of what has been happening in Güssing since the early 1990s with decisive involvement of EEE. Since every region has certain resources in different measures, the model can serve as an example for many communities which want to establish themselves as an island of sustainability. The project team attended a presentation by the European Centre for Renewable Energy which provided it with a good overview of the Model Güssing. Below you will find a short summary of two of the four visited plants in the Municipality of Güssing. Biomass power plant Güssing - Fluidised steam gasification (Thermal Gasification) In order to make the generation of electricity from biomass possible also in small, decentralised power stations, a new type of power station was realised for the first time in Güssing. For this purpose a gasification procedure is used, which offers particularly combined heat and power-(chp)-advantages in comparison with heat-only procedures. In the biomass CHP station of Güssing, 4,500 kw district heating and 2,000 kw electricity originate from 2,360 kg wood per hour. In order to realise this project from the idea to the completed plant, the partners REPOTEC, as design engineer, scientists from the Technical University of Vienna, the EVN and the District Heating Güssing priv.ltd.co. formed the authority network RENET and developed this new, from the economic and technical point well planned system of CHP on the basis of biomass gasification. 2

3 Steam gasification The heart of the power station is the WIRBELSCHICHT (fluidized bed-) steam carburetor. It consists of two connected fluidised bed systems. During gasification the biomass is gasified with approximately 850 degree C under supply of steam. Using water vapor instead of air as a medium of gasification results in a nitrogen free, tar-poor product gas, with a high heating -value. A part of the remaining coke is transported to combusting over a circulating bed material (sand), which acts as heat distribution media. The heat dissipating to the bed material is needed for the maintenance of the gasification reactions. The flue gas is carried off separately, and the contained heat is used for district heating. Gas cooling and gas cleaning For the function of the gas engine which is installed subsequently, the product gas would be cooled and cleaned. The remaining useful heat is used again for district heating. As a next step, the gas is freed from dust in a woven filter. After this procedure a scrubber reduces the concentrations of tar, ammonia and sour gas components. Due to this special procedure it is possible to lead back all residual substances into the process. As a consequence neither wastes nor waste water result during gas cleaning. Gas engine The gas engine converts the chemical energy of the product gas into electricity. Beyond that, the waste heat of the engine is used as well for the production of district heat. The efficiency obtained by that way is so far unique for biomass-utilization. The electrical efficiency is 25-28%, the overall efficiency (electricity and heat) is even more than 85%. 3

4 Biogas facility in Strem - Biogas (Biological gasification) The Biogas Strem Errichtungs- und Betriebs GmbH & Co KG is the operator of a biogas facility with 500 kwel power that has been built up next to the biomass facility of the Öko Energie Strem agricultural association since November This project aims at producing electrical and thermal power from locally available, renewable energy sources (the NAWAROs are the re-growing raw materials like grass, clover, maize, sunflower etc.). The produced thermal energy is fed into the local district heat network, while the electric energy is fed into the local electricity network according to the tariff defined in the eco-power act. The eco-power act prefers such power, which is produced from renewable energy sources. In case of a biogas facility with 500 kwel the tariff rate of 14,5 Cent/kWh is ensured for 13 years. In several cases the reorganization of agricultural facilities from full-time to part-time operation has resulted in the decreasing of livestock husbandry, consequently due to the reduced livestock production the meadows were not utilized any longer and the ploughland became fallow. This means that enough land is available for renewable energy sources in direct vicinity to the biogas facility. These plants would be grown by environmentally safe and sustainable agricultural methods, the required raw material quantity would be available with minimal transport cost. The biogas facility in Strem has special relevance from the viewpoint of biogas technology development and it became a research and demonstration facility by the scientific support of the RENET-Austria in the following fields: Running-in facility, optimization, dry fermentation Optimization of process technique and reactor load Partial reformation Expert system for process control. Short description of dry fermentation process Green silage is fed into a heated and continuously mixed fermenting tank made of armoured concrete. In order to reach the proper dry substance concentration and digestion chamber load, the substrate should be diluted with fresh water and/or by feeding back of fermented substrate. The created substrate mixture is fermented by micro bacteria. Then, following the separation of solid materials from the bio-gas it is pumped into an interim storage tank (post fermentation tank) equipped with a gas storage tank. The bio-gas is converted to electrical and thermal energy in a CHP. The minor part of the produced electrical and thermal energy is fed back into the cycle of the equipment, while the major part of the produced power is fed into the public network on the advantageous feed-in-tariff according to the eco-power regulation act. The liquid fermentation residue and the separated solid materials, which mean clearly biological and very valuable manure, are stored in two lagoons and fed back to the agricultural cycle for fertilizing. 4

5 Technical data Bio-gas facility in Strem Power: 500 kw electrical 600 kw thermal Annual energy production: MWh electrical MWh thermal This amount of energy means electrical power supply of 1,200 average households and thermal supply of 40 households.. Annually required plant quantity: 11,000 t (250 ha) Total investment cost: 2.25 Mio. 5

6 Aim of the Hungarian study tour Within 4biomass project we wanted to share the existing experiences regarding biomass use in Hungary. Two interesting projects were chosen near to the Austrian border to disseminate demonstration projects to the project partners. The aim was to find places where biomass resources are used sustainably and close to the place where the raw material is generated. At the first location we presented an example of a biomass based village district heating system in Pornoapati, the first and untill now the only one in Hungary. The second sight was the Monastery of Pannonhalma, where the monks are utilizing their garden residues for heating purposes in wintertime. At both places participants received detailed description of the plants and a complete site visit. The incurred questions were also answered. Location 1: Biosolar village heating system in Pornóapáti System The small village -with 392 residents- can be found near the Austrian border. The district heating plant in Pornóapáti was built in 2005 and it provides heat for public buildings (729 GJ of heating and 88 GJ of DHW), for 104 households (6,402 GJ of heating and 894 GJ of DHW) and for enterprises (760 GJ of heating and 20 GJ of DHW) through the local small scale district heating system. A 2.2 km long main DH pipe line, 1.3 km access pipe was built. Currently, the annual heat demand is entirely covered by the 2 biomass boilers with nominal capacity of 2*600 kw. Raw material During the visit we have learned that the necessary raw material (wood chips) is collected from a local wood processing company as well as from the local woods. 400 t/year of wood residues from the local wood processing company and 654 t/year wood chips from the local forests is utilized. Future The heating plant is planned to include a 465m2 solar collector system, which would entirely cover the heat demand of domestic hot water (DHW) production. If it is built the operation of biomass boilers would be needed only for the heating season and the solar collector would satisfy the DHW needs during summer. At the first stage of the realization, only the installation of the biomass heating plant and the establishment of the local district heating system were possible. However, the heating plant and its surrounding was arranged so that it could be supplemented with the 465m 2 solar collector system. It can only be realized in the near future and it would require national or EU support. After the investment is finished 1,168 tonnes of CO 2 saving can be reached annually. 6

7 Success In Austria hundreds of village district-heating plants exist, but in Hungary till now only this plant exists. The success lies in the special circumstances that existed in the project development phase. First of all a committed leader was needed and Walter Purker, the mayor was the right person to formulate the opinion of villagers and initiate the project. Luckily the gas pipe was not built in the village, so people could be convinced to choose the convenient non-fossil fuel based district heating solution. The location was also a great help. First of all the closeness to Austria and secondly the availability of vast resources were the main driving forces. With the help of Austria they applied for the Phare CBC Program cross-border environmental protection infrastructure networks program and they recieved funding (55% of investment). Luckily other sources of funding were also available. Location 2: Monastery of Pannonhalma Background The Abbey of Pannonhalma is one of the most precious scheduled monuments in Hungary. It plays a significant role in the Hungarian education and culture. The Abbey annually hosts about 80-90,000 guests. For this reason the installed renewable technologies function as demonstration project for the wide public. The purpose of the project was to make the energy system more efficient and environmental friendly. System In 2009, a wood chips boiler and a CHP (Combined Heat and Power) unit were installed and the old low efficiency boilers running on natural gas were removed. The new biomass boiler with 700kW thermal capacity is fed with residues from the local agriculture and forestry and supplies heat for the Abbey's heating and DHW (Domestic Hot Water) system. The capacity of the biomass boiler covers 60% of the peak heat demand (including both heating and DHW demand) of the Abbey. In this way it supplies 80% of the annual heat demand of the local buildings. Peak demand appears during the cold season; therefore the biomass boiler is turned on only during winter time. 7

8 Besides the biomass boiler, a natural gas based CHP unit was installed to provide heat and electricity for local use. The CHP unit can cover about 10% of the peak heat demand (including both heating and DHW demand) and 40% of the peak electric demand of the Abbey. This means that the CHP unit supplies about 30% of the annual heat demand and 76% of the annual electricity demand of the local buildings. The generated electricity is not fed into the public electric grid; it is entirely used for supplying local demand. Almost 700 MWh of electricity can be generated with the unite annually Heat demands are always higher than the capacity of the CHP unit. In winter the CHP unit provides heat for DHW and partly for heating purposes. The remaining part of the heat demand is covered by the biomass and gas boilers. The biomass boiler satisfies the base load of the system, the gas boiler is activated only in winter peak periods. If the local electricity demand is low then the CHP unit operates at a lower capacity producing less heat. In this case the biomass and gas boilers operate at a higher capacity covering the remaining heat demands. In summer, the CHP unit can entirely satisfy the heat demand of the DHW production therefore the biomass and gas boilers are switched off all during the summer season. Financial support The Abbey is very successful in applying for EU and national funding. They have received 193 million HUF (50% of investment) non-refundable subsidy through the Energy and Environment Operational Programme for the biomass boiler and the raw material storage. Further 23.6 million HUF subsidy was received for the gas motor (CHP unit). Currently a new project development is in place, where the Abbey is willing to install 400m2 solar panel system that could generate almost 75 thousand kwh electricity per year. Raw material The Abbey has an advantageous location to use agricultural and forestry residues. About 955 tons vine stem, lavender stem wood residues are used annually coming from the Abbey's wine yard and lavender plantation. Also the wood residues of their arboretum are utilized. But this amount only covers 30-50% of row material needs and the rest is bought from the nearby Kisalföld Forestry Inc. The raw material is kept in a dry storage. CO2 savings With the biomass boiler 557 t of CO2 emission can be saved annually. The high efficiency Combined Heat and Power unit can reduce the emission further by 455 tons a year. 8