GROWING POWER. Advanced solutions for bioenergy technology from Finland

Transcription

1 GROWING POWER Advanced solutions for bioenergy technology from Finland

2 Edition: Tekes / VTT Processes / Teonsana Oy Graphic Design: Oddball Graphics Printed by: Markprint Oy, Lahti, 2002

3 Bioenergy equals green energy AS WE MOVE INTO THE 21 ST CENTURY, environmental considerations are becoming the factor that dictates energy production choices in industrialised countries. Promotion of use of renewable energy sources has gained real impetus in the last few years, when global warming and the need to develop a strategy for stabilising CO 2 emissions have made renewables more and more attractive. The Kyoto Protocol mandates that industrialised countries reduce greenhouse gas emissions to 5.2 per cent below 1990 levels by the years In late 1997, the European Commission published a White Paper on promoting the use of renewable energy sources. At community level, the target is for renewables to account for 12 per cent of total energy consumption by 2010, as against the 1995 figure of 6 per cent. Bioenergy will play a leading role in doubling the use of renewables. The target is to increase the annual use of bioenergy from 45 Mtoe to 135 Mtoe. In 2001, the European Commission introduced a Green Paper Towards a European strategy for the security of energy supply, which highlights also the importance of renewable energy sources. New EU directive sets targets to increase the share of renewables to 22.1 per cent in total Community electricity consumption by Metla/Erkki Oksanen Aims for bioenergy utilisation in Finland in 2010 and a vision for 2025 Mtoe year Domestic use District heating Industry Source: The Action Plan for Renewable Energy Sources Metla/Erkki Oksanen 3

4 The primary energy consumption in 2000 Total energy consumption 31.2 Mtoe Turku Energia Coal Oil Natural gas Hydropower Wood fuels Other Nuclear power Net imports of electricity Peat Oil 26.9 % Nuclear power 18.0% Net imports of electricity 3.3% Peat 4.4 % Other 0.7 % Wood fuels 20.8% (black liquor, wood residues, firewood) Hydropower 4.0% Natural gas 10.8% Coal 11.3% Source: Energy Statistics The distribution of wood fuel consumption in 2000 Total wood fuel consumption 6.4 Mtoe Firewood Black liquor Wood residues Black liquor 52.8% Wood residues 30.4% Firewood 16.8% Source: Energy Statistics The Finnish electricity market was liberalised in The liberalised market calls for efficient heat and power generation in an environmentally acceptable way. The success of several biomass power plant projects launched in the late 1990s indicates that bioenergy has considerable potential in liberalised markets as well. Primary energy sources in electricity production in 2000 Total electricity production 79.2 TWh Nuclear power Coal Oil Natural gas Hydropower 18.3% Wood fuels and other indigenous 11.7% Peat 5.0% Wind energy 0.1% Net imports 15.0% Natural gas 10.0% Oil 1.9% Coal 10.6% Nuclear power 27.3% Hydropower Wood fuels Peat Wind energy Net imports Source: Adato Energia Oy An important role in the Finnish energy system Renewable energy sources accounted for 25 per cent of the total consumption of energy in Finland in 2000, which was 31.2 Mtoe. In addition to wood and wood based fuels such as solid wood residues and black liquors from the forest industry, this calculation includes hydropower, wind power and recycled fuels. The National Climate Strategy, launched by the Finnish Government in 2000, highlights the targets and measures to meet the Kyoto commitments in Finland. By the years emissions of greenhouse gases should be reduced to the level of 1990, when they were equivalent to around 76.5 million tons of carbon dioxide. In order to meet the target, it is necessary to implement an energy conservation programme and a programme promoting renewable energy sources. Together these two programmes may account for about half of the targeted emission reduction. The Finnish Action Plan for Renewable Energy Sources launched in 1999 has the objective of doubling utilisation of renewable energy sources (12.3 Mtoe) by 2025, as compared to the situation in 1995 (6.1 Mtoe), when their share was 21 per cent of the total energy consumption. By 2010, the use of renewable energy sources should be 50 per cent higher (3 Mtoe) than in the reference year Their proportion will be roughly 27 per cent of the Vapo 4

5 total consumption. The target for 2010 was confirmed in the National Climate Strategy in June In the attempt to reach the targets, wood based fuels and recovered fuels play a leading role in Finland. The increase in the use of renewable energy sources will be obtained almost entirely from bioenergy. Timberjack Measures to maintain biofuel competitiveness Production and utilisation of renewable energy have been promoted for a fairly long time by providing funds for research and development and by introducing financial and fiscal measures, such as energy taxation of fossil fuels and grants for investments or support for electricity production from renewable energy sources. In 1990 Finland was the first in Europe to introduce CO 2 taxation. In heat generation biofuels are not taxed, because net CO 2 emissions from their use are small, even including the harvesting and transport. To maintain biofuel competitiveness in power generation, a tax subsidy was introduced in 1997, when fuel taxes were replaced by taxes on electricity consumption. The growth of Finnish forests exceeds the drain so that wood resources increase by about one per cent annually. This amount of biomass, over 20 million m 3 solid, has a thermal value corresponding to that of nearly 4 Mtoe. Fortum In Finland, biofuels are cofired in large-scale applications. Successful and efficient cofiring requires advanced control systems for combustion and fuel feeding. 5

6 Finland, the number one in bioenergy FINLAND IS THE WORLD LEADER in the utilisation of bioenergy and in the development of biomass combustion technologies and efficient fuel supply chains. The expertise extends from the forests to heating or power plants, from root to soot. One of the strengths of Finland s energy economy is the varied nature of the energy production structure. Wood and wood based fuels play an important role in the decentralised and diversified energy system. Finland s geographic and climatic features, as well as the important role energy-intensive industries play in the economy have spurred the development of efficient energy systems. The pulp and paper industry supplies over two fifths of the heat and electricity it needs by utilising its solid and liquid wood residues. This has created a natural context for the development of relevant bioenergy technology. The chemical recovery boilers and solid wood residue fired boilers required by the forest industry have supported the development of solid fuel power boiler technology which is suited for a variety of biomass and waste fuels. Strong technological expertise Combined heat and electricity production (CHP) based on local fuels accounts for the bulk of bioenergy production in Finland. A technology closely linked with large-scale cogeneration is fluidised bed combustion (FBC). FBC boiler technology has been scaled down for application in small-scale biomass fired CHP plants (< 5 10 MW e ) as well. Grate firing of biomass has traditionally been used for small heating applications (under 5 MW th ). LMH Hakkurit Oy PVO Combined heat and power production accounts for the bulk of Finnish energy production. The large-scale applications utilising CHP are located primarily on forest industry sites where biomass is abundantly available. 6

7 Fortum Sermet Wood residues, such as sawdust and bark, are efficiently utilised in energy production. Their moisture content being over 50 per cent, this requires state of the art combustion technology. Small-scale CHP offers an environmentally sound way to produce energy for local use from locally available fuels. Finland has a long tradition of using biomass CHP technologies. The first industrial cogeneration plants were built at the turn of the 1920s and 1930s, followed by the first district heating plants in the 1950s. In larger plants, FBC technology developed in Finland in the 1970s for the combustion of biomass and other low-grade fuels, has become the dominant technology. At the same time fuel handling technologies have been developed and a lot of effort has been focused on utilising wood residues from the forest industry. In recent years, the use of forest residues has been increasing. Cost of fuel procurement has been reduced by integrating the fuel and raw material supply chains. VTT During the last 20 years, gasification technologies have been developed in Finland and a variety of commercial solutions have been launched in the market. 7

8 Alholmens Kraft Wood fuel fired plants in operation/planning stage in Finland in Plant type Number Electricity output Heat output Boiler output of new plants MW e MW th MW th built after 1997* Municipal CHP plants Municipal DH plant Industrial CHP plants ,600 Industrial steam boilers In 2000 there were 375 plants fired with solid wood fuels in Finland. They were using 2 Mtoe of solid wood fuels. Condensing plants Total ,015 3,450 * some of them are retrofits of existing plants Source: Elektrowatt - Ekono Liberalised electricity market a challenge for RES The Finnish electricity market was liberalised in 1996, which has changed the market completely. Liberalisation is a challenge for renewable energy sources. In the liberalised market the price of electricity has come down and electricity generation has faced new demands; production has to be more profitable than before which is also the case with procurement of biofuels. In order to keep small CHP plants profitable, a tax subsidy has been introduced for biomass fuelled plants. Liberalised energy markets promote widespread application of high efficiency, local and on-site generation of heat and power in an environmentally acceptable way. Biofuels are suitable for this kind of generation. In the late 1990s, several biomass power plant projects were launched especially in forest industry in Finland. Moreover, a number of wood fuel procurement organisations were established to supply forest fuels or pellets. Better competitiveness with intensive R&D In Finland, great emphasis has been given to wood based fuels in the development of energy technology. As a result of these R&D activities, the production cost of fuels from forest residues has been reduced considerably, resulting in a rapid increase in the use of forest chips in recent Vapo In an innovative fuel procurement chain a key for profitable production of bioenergy the fuel is not stored at the plant. Delimbed trees or logging residues are stored in the forest, chipped at a terminal and transported to the plant by trucks. 8

9 Advanced production and transportation technologies are utilised in wood fuel procurement. years. In addition to machine development, the focus has been on reducing harvesting and transportation costs by improving logistics and applying modern information technology solutions within the supply chain. Also, increased know-how in combustion technologies has enabled efficient and environmentally acceptable utilisation of low-grade fuels. The development of fluidised bed combustion technology during the last 20 years provides a good example. Finland is a trendsetter in combined heat and power production, with CHP plants accounting for over 30 per cent of the total electricity production both in industry and larger municipalities. Technological competitiveness has resulted in rapid growth of energy technology exports. The total value of exports increased almost fourfold throughout the 1990s, reaching EUR 3.3 billion in Vapo Timberjack Timberjack Pellets have been replacing fuel oil when old oil fired boilers at schools and other municipal buildings have been converted to biofuels. 9

10 Fortum Cofiring increases the fuel range and fuel flexibility. In some Finnish power plants up to five different fuels are combusted together. The use of logging residues will be increased by developing harvesting methods and by improving the quality of forest chips. Vapo Fuel flexibility with cofiring Quite often, energy production based on biomass is hampered by limitations in the supply and/or fuel quality. That is why cofiring with two or more fuels is widely used. This is especially true in large-scale electricity production, where the biomass can seldom meet the total fuel demand in a cost-efficient way. Successful cofiring of biomass requires attention to the fuel properties and mixing techniques. Various types of biomass are frequently burnt together with peat or coal. In some Finnish power plants, up to five different fuels are combusted together. Fuel flexibility ensures the economical operation of the plant even when there are seasonal limitations with some sources of the fuel supply. Fluidised bed technology is applied to a wide range of fuels, from very moist fuels like bark and sludges up to high-grade fossil fuels. Multifuelled fluidised bed boilers achieve fuel efficiency rates over 90 per cent even with difficult, low-grade fuels. Retrofitting of old pulverised fuel fired boilers to burn biofuels increase the fuel range and flexibility. Separate biomass gasifiers, which can also use wet biofuels and REF, are one of the tested solutions for existing pulverized coal fired plants. Fluidised bed gasifiers can make efficient use of locally available fuel with low investment costs. Gasification of biomass and co-combustion of the biomass derived product gas in existing coal-fired boilers offer several advantages: minimal environmental impact with low investment and operation costs. Local fuels efficiently used for heat supply In Finland, space heating accounts for about 20 per cent of the primary energy consumption. Most of the heat is generated by CHP technology or by local district heating plants. Especially in rural areas and in one-family houses, however, separate heating systems are needed. There is increasing interest among municipalities and industry to heat their own buildings and facilities by locally available fuels. This is a question of boosting the local economy, too. In Finland, cooperation between industrial plants and municipalities has been a success when the partners have been organising heat supply together utilising biomass fuels. In these cases, the plant together with the local agricultural businesses provides the fuels. The power 10

11 Nunnauuni Almost 90 per cent of the new detached houses have a fireplace or stove made of heatretaining material. Usually it is used as an auxiliary heat source. plant and the required other investments are financed by the municipality or other partners. Raw material use and energy recovery are kept in balance in the wood procurement chain. Biomass is typically a local fuel, limited in supply and cost-effective only within a restricted distance. Given suitable combustion technology, the conversion of oil-fired boilers to burn locally available biomass constitutes a bioenergy niche with considerable potential in many countries. Honkarakenne Cooperation, the key to success Good cooperation between Finnish companies, research organisations, universities and public authorities has been the key to the success of the Finnish energy technology sector. The energy cluster of energy producers, consumers, equipment manufacturers and specialist organisations in the energy sector provides synergetic advantages. The cluster is particularly important for business chains and technology development. Emphasis on the chain of research, development, demonstration and commercialisation has been fruitful. The development of FBC technology, from bubbling fluidised bed to circulating fluidised bed combustion and on to advanced gasification, is a good example of this. Cooperation between industrial companies and municipalities regarding the heat supply is also very common. A municipal plant may provide process steam to a local factory, or conversely an industrial heating plant may supply district heat to local consumers. Finnish companies tend to work together to implement projects both with domestic partners and local foreign partners. In large export projects, close cooperation, from consultancy and planning to final delivery of the plant, enables the client to find the most efficient and environmentally sound solution. Cooperation between industrial companies and municipalities in energy business is very common. In many cases, the company supplies the fuel and buys most of the energy produced by the municipal power plant. 11

12 The forest industry, the main provider and user of wood based energy IN FINLAND, the main provider and user of wood based energy is the forest industry, which gets the wood fuels at a competitive price in connection with raw material procurement or as a by-product of wood processing. This creates a natural context for the development of bioenergy technology. About 6.5 Mtoe of wood based fuels (35 million m 3 solid, calculated as wood) are used in Finland annually for energy production, covering 20 per cent of the total consumption of primary energy. Most of the wood based energy is recovered from liquid and solid industrial wood residues. Only a modest share comes from the forest chips and traditional firewood. The total share of wood based energy in Finland is higher than in any other industrialised country in the world. Nevertheless, our goal is to increase the energy use of wood fuels. In the Finnish conditions, this is considered one of the most efficient ways to reduce greenhouse gas emissions. Since all industrial wood residues are already used either as raw material or to produce energy, any increase must be based primarily on the recovery of unutilised biomass reserves in the forests. LOGGING RESIDUES BUNDLING METHOD Bundling of logging residues Forest haulage by tractor equipped for log haulage Transportation by log trucks Logging residue compacting truck trailer On-road transportation of loose logging residues TERRAIN CHIPPING METHOD Forest haulage CHIPPING IN ROAD SIDE METHOD Chipping of residues at road-side terminal LOOSE RESIDUES Crushing of bundles or loose residues at the plant Transportation of forest chips VTT Different methods are used in the wood procurement of forest chips. 12

13 Timberjack Finnish timber harvesting organisations apply modern technology and efficient logistic chains to supply the raw material to the industry. By integrating wood fuel production with the industry s raw material supply chain, it is possible to achieve economies of scale and reduce transportation and overhead costs. The nominal price of forest chips has declined by 35 per cent over the past two decades, thanks to a general decline in procurement costs of industrial timber, technological advances in forest chip production technology and the related procurement logistics as well as increased production volume. When logging residues are recovered from regeneration areas, fuel transport makes up almost half of the total cost. Compacting logging residues to bundles makes it possible to apply standard forwarding and trucking equipment for off-road and on-road transportation of forest biomass. Modern information and satellite technologies will be applied in the future to make the logistics more economical. The development of the price of wood fuels EUR/GJ Bark 2. Sawdust 3. Ind. wood residues 4. Forest wood

14 Paper mill looking for fuel flexibility THE KAIPOLA POWER PLANT at the UPM-Kymmene Paper Mill uses the latest solid fuel combustion technology in energy production. The fluidised bed boiler produces steam for paper drying and for a turbine that generates 9 per cent of the mill s annual electricity consumption. A wide range of different fuels can be burnt independently or mixed. The main fuels are wood fuels, various sludges and peat. The share of coal is 1 per cent. Thanks to the modern and efficient flue gas treatment, emissions of dust, sulphur dioxide and nitrogen oxides are low and well controlled. The UPM-Kymmene Kaipola Paper Mill produces newsprint, telephone directory paper and LWC printing paper for magazines, sales catalogues etc. The production capacity of the mill is over 650,000 tons per year. Timberjack Technical data Owner UPM-Kymmene Group Commissioned 1991 Electricity output 26 MW e Fuel data Annual fuel consumption 2,963 TJ Fuel distribution Bark and chips (from the mill) 15% Sawdust and bark (purchased) 20% Deinking and effluent treatment sludges 15% Forest chips 18% Sod peat 12% Milled peat 13% Coal 1% Oil 8% Boiler data Boiler supplier Kvaerner Pulping Oy Boiler type Bubbling fluidised bed boiler Boiler output 104 MW Steam values 40 kg/s, 115 bar, 530 C UPM-Kymmene utilises new advanced technologies to harvest small trees from thinning operations. UPM Kymmene Heinola Sawmill Machinery The forest chips are produced mainly using logging residues from the final cutting of spruce stands. Procurement of fuel is integrated in the raw material supply chain of the plant. 14

15 CHP for log house factory and district heat HONKARAKENNE OY, a wood processing company that manufactures log houses, plays a key role in the Karstula CHP plant in Central Finland. The company supplies the fuel and buys most of the energy produced by the plant. The plant is owned and operated by Puulaakson Energia Oy, whose owners are Honkarakenne, the municipality of Karstula, and Keski- Suomen Valo (Vattenfall), a local energy utility. The plant produces 3 MW of process steam and heat for Honkarakenne and at maximum 6 MW of heat for the municipal district heat network. Moreover, 1 MW of electricity is generated for the needs of Honkarakenne. A similar plant is in operation at a sawmill owned by Iisalmen Sahat Oy in Iisalmi, Finland, as well as at a sawmill in Tranås, Sweden. The plant was delivered as a factory-made module by Sermet Oy, a Finnish boiler manufacturer. The plant deploys a patented combustion technique called BioGrate, which is capable of burning biomass fuels with a moisture content of up to 65 per cent. In addition to the strong position Sermet has in the Finnish market, the company exports its boiler technology to the Baltic countries, Canada, France, Russia and Sweden. Wärtsilä Corporation, a global ship power supplier and a provider of solutions for distributed power production, is a new owner of Sermet Oy. With its global sales and project management network the corporation strengthens the sales and marketing of the Sermet biomass boilers. Feed water pumps Fire tube Steam boiler Sermet BioGrate Water treatment Mw e 2 7 Mw th p = 22 bar T = 350 C Steam gas removal PRV Cooling Pressure control Steam engine Network synchronizing Generator Steam/oli separator Hot water to district heating network Condensate pumps Active carbon filter Condensate tank Hot water to drying kilns Technical data Owner Puulaakson Energia Oy Commissioned 2000 Investment cost EUR 4.34 million Electricity output 1 MW e Process steam output 3 MW th District heat output 6 MW th Annual electricity output 5 GWh Annual heat output 162 TJ Fuel data Annual fuel production, total 250 TJ Fuel distribution Cutter shavings 44% Bark 30% Sawdust 26% A Primary combustion chamber with roating grate B Secondary combustion chamber C Fire tube boiler D Flue gas fan E Flue gas filter F Stack G Submerged ash conveyor and container Boiler data Boiler supplier Boiler type Boiler output Sermet Oy BioGrate 10 MW th The plant utilises the BioGrate boiler technology developed by Sermet Oy, a Finnish boiler manufacturer. Honkarakenne The Karstula plant produces process steam, heat and electricity by burning wood residues from the Honkarakenne log house factory. Sermet Sermet A majority of the Honkarakenne log houses are delivered to international markets. 15

16 CHP by cofiring large scale solutions for the needs of industries and utilities The energy utility of Turku is one of the large utilities using pellets in a 100 MW th coal fired boiler. Large investments were unnecessary: only the fuel storage and handling system had to be built. Turku Energia LARGE-SCALE UTILISATION OF WOOD FUELS is focused primarily on forest industry sites where biomass is abundantly available. Wood fuelled plants frequently operate in conjunction with a pulp and paper mill or a sawmill. Large-scale plants apply CHP technology, i.e. they generate electricity and provide steam for industrial processes or the district heating network of a nearby town. Integrating the wood fuel supply into the forest industry s raw material procurement and processing makes power plant operation cost-effective, competitive and environmentally sound. In large-scale plants, fluidised bed combustion (FBC) technology has become the dominant solution in Finland. FBC was developed in the 1970s for the combustion of biomass and other low-grade fuels. The capacity of fluidised bed boilers currently operating in Finland totals 1,900 MW e. Finnish companies have played an important role in the development of FBC technology. From bubbling fluidised bed Cofiring enables burning of a wide range of fuels. combustion to circulating fluidised bed combustion and on to advanced gasification and pressurised concepts, Finnish expertise has produced boiler technology that occupies a strong position in the world market. Finnish manufacturers have supplied more than 50 per cent of the world FBC boiler capacity. Cofiring is a promising technology for simultaneous use of different kinds of biofuels in large-scale utility boilers that use fossil fuels as their main fuel. It is also commonly used in the power boilers at pulp and paper mills. FBC technology with versatile fuel flexibility is very appropriate for cofiring. Another solution is to fit a separate biomass gasifier to work with an existing pulverised fuel-fired boiler. VTT Roxon Power plants with fluidised bed boilers burning recovered fuels REF have higher efficiencies in electricity production compared to mass-burning of unsorted waste in grate firing. Co-combustion of good quality REF in grate and fluidised bed boilers will also be a feasible alternative in the future. Gasification with advanced, low-cost fuel gas cleaning is an option for the co-combustion of REF of lower quality. 16

17 Foster Wheeler A circulating fluidised bed boiler (91.2 MW) of Birka Energi, a Swedish energy company, in Högdalen, Sweden burns recovered fuel with forest residues, sawdust, bark and wood briquettes. In a fluidised bed boiler fuel is fed into a solid bed which has been fluidised, that is, lifted off a distribution plate by blowing air or gas through the plate. The amount of bed material is very large in comparison to that of the fuel. The large heat capacity of the bed material stabilises the combustion process. The difference between the bubbling fluidised bed combustor (BFB) and the circulating fluidised bed combustor (CFB) turns on the velocity at which gas is blown at the bed. In a BFB combustor air velocity is lower and the particles behave like a boiling fluid but stay in the bed. In a CFB combustor air velocity is higher and a large proportion of the bed material leaves the bed and is collected by cyclone separators before recirculation to the bed. CFB boilers are better suited for coal because the fuel is recirculated to the bed through the cyclone, extending the time it stays in the combustor. Roxon Foster Wheeler 17

18 A CHP boiler retrofitted to increase the use of wood fuels THE RAUHALAHTI CHP plant of Jyväskylän Energiantuotanto Oy provides energy for the town of Jyväskylä and the M-real Kangas Paper Mill. Jyväskylä, a town of 80,000 inhabitants is located in Central Finland. The boiler at the Rauhalahti CHP plant, originally commissioned in 1986, was converted from pulverised firing to fluidised bed combustion in The conversion of the boiler significantly improved the profitability, availability and emission control of the plant. Around 50 suppliers are responsible for fuel procurement, mainly of wood and peat. This sets special requirements for the management of the fuel supply chain. As much as 25 per cent of the fuel consumption is covered by wood based fuels. The conversion to fluidised bed technology has made it possible to utilise a wide range of fuels, including moist wood and bark. The increased use of biofuels has reduced CO 2 and sulphur emissions. The share of wood will be 50 per cent of the total fuel consumption at the Rauhalahti CHP plant in the near future. Fortum The plant produces district heat for the town of Jyväskylä, process steam for the Kangas Paper Mill and electricity for the grid. The energy company Jyväskylän Energiantuotanto Oy is a joint venture of Fortum a Finnish energy company and the town of Jyväskylä. Finnish boiler companies, Foster Wheeler Energia Oy and Kvaerner Pulping Oy have retrofitted almost 60 boilers to fluidised bed combustion of biofuels to increase the use of wood fuels in existing plants. Technical data Owner Jyväskylän Energiantuotanto Oy Commissioned 1986 Conversion 1993 Electricity output 87 MW e Process steam output 40 MW th District heat output 140 MW th Annual electricity production 399 GWh Annual heat production 3,809 TJ Fuel data Annual fuel consumption 6,500 TJ Fuel distribution Peat 67% Industrial wood residues and forest chips 25% Coal 6% Oil 1% REF 1% Boiler data Boiler supplier Kvaerner Pulping Oy Boiler type Retrofit to bubbling fluidised bed Boiler output 295 MW th Steam values 110 kg/s, 135 bar, 533 C Viherlandia The large greenhouse premises of Viherlandia are heated with district heating water returned from the Jyväskylä district heating network. 18

19 Innovative forest fuel management for a giant-scale biofuelled plant THE ALHOLMENS KRAFT CHP plant in Pietarsaari, a town of 20,000 inhabitants on the western coast of Finland, is a unique illustration of the possibilities of biofuel based energy. The plant produces steam for the adjacent paper mill and for a utility generating electricity and heat. A UPM- Kymmene Pulp and Paper Mill nearby supplies the power plant with wood and bark residues. The mill produces almost 600,000 tons of pulp, 159,000 tons of paper and 95,000 tons of packaging materials. The innovative forest fuel procurement system is based on bundling logging residues from regeneration areas. Since the plant is of giant scale, special attention has been paid to the logistics of fuel procurement. The goal is to use at least 200,000 solid m 3 (1,440 TJ) of logging residues annually. These are hauled to the plant as loose material or, more frequently, in compressed bundles, and then crushed at the plant. The fuel range of the plant is extremely diverse. The design of the plant allows great fuel flexibility a fact that makes it feasible almost anywhere in the world. The heavy fuel oil and coal are only reserve fuels for exceptional cases, such as problems with fuel handling. The Alholmens Kraft plant is the largest biofuelled power plant in the world. Technical data Owner Alholmens Kraft Ltd Commissioned 2001 Investment cost EUR 170 million Electricity output 240 MW e Process steam output 100 MW th District heat output 60 MW th Annual electricity production 1,300 GWh Annual heat production 2,520 TJ Fuel data Annual fuel consumption 12,600 TJ Fuel distribution Industrial wood and bark residues 35% Forest residues 10% Peat 45% Heavy fuel oil or coal 10% Boiler data Boiler supplier Kvaerner Pulping Oy Boiler type Circulating fluidised bed combustion Boiler output 550 MW th Steam 194 kg/s, 165 bar, 545 C The Alholmens Kraft CHP plant is a good example of how biofuels can also be burnt in larger applications. The design of the boiler allows great fuel flexibility. Timberjack Alholmens Kraft Kvaerner Pulping There are special requirements for the fuel supply management because of the size of the plant. The innovative fuel procurement system is based on bundling the logging residues. 19

20 Efficient way to cofire a gasifier for a coal fired utility boiler AN EFFICIENT WAY TO USE LOCAL BIO- MASS FUELS and even recovered fuels for energy is to gasify these fuels in a separate gasifier and cofire the cleaned product gas in existing pulverised coal fired or fluidised bed boilers. The same concept applies to oil and gas fired boilers. Gasification solutions are also attractive when cofiring straw in a coal fired boiler. In Finland, two fluidised bed gasifiers, one in Lahti and another in Varkaus, are successfully in operation, and several new investments are being planned. The Lahti gasifier replaces 15 per cent of the fossil fuel and A reliable feeding system for fuel mixtures is essential for the availability of the boiler. significantly reduces SO 2, NO x and CO 2 emissions. The fuels burnt in the gasifier are different types of solid biofuels. A similar gasifier with flue gas cleaning equipment will be installed at a power plant of the Electrabel company in Ruien, Belgium. Roxon Lahti Energia Technical data Owner Lahden Lämpövoima Oy Commissioned 1998 Electricity output 185 MW e Heat output 250 MW th Fuel data (gasifier) Annual fuel consumption 1,200 TJ Fuel distribution Wood residues 57% REF 42% Other 1% Gasifier data Gasifier supplier Gasifier type Gasifier capacity Foster Wheeler Energia Oy Circulating fluidised bed gasifier MW depending on the moisture content and heating value of fuels The Lahti CFB gasifier, connected into a 350 MW pulverised coal fired boiler, has been in operation since Biomass or recycled fuels Fuel feed system Bed materials CFB gasifier Gas cooler boiler Main boiler feed water Sorbent Main boiler furnace Filters LP steam Fly ash A CFB gasifier with fuel gas cleaning system. 20

21 A utility boiler that relies on wood Vapo The Forssa CHP plant cofires a wide range of wood based fuels. THE FORSSA CHP plant produces 48 MW of heat and 17 MW of electricity for Forssa, a town of 19,000 inhabitants located about 100 km northwest of Helsinki in Southern Finland. District heat for the town was generated by burning fuel oil until autumn 1996, when this biofuel fired power plant was commissioned. Main fuels burnt in the plant s BFB boiler include industrial wood residues and forest chips. Also, smaller amounts of recovered fuel and peat are used. Annual wood fuel consumption at the plant is about 400,000 bulk m 3 (670 TJ). Biowatti Oy, a Finnish wood fuel production and marketing company, has responsibility for the delivery of all wood fuels. Prices are set on the basis of the energy generated and the efficiency of the boiler. S. Pinomäki Ky Technical data Owner Forssan Energia Oy Commissioned 1996 Electricity output with auxliary condensing unit 17.2 MW e Heat output 48 MW th Annual electricity production 57 GWh Annual heat production 559 TJ Fuel data Annual fuel consumption 760 TJ Fuel distribution Bark 25% Sawdust 29% Forest chips 34% Sod peat 6% REF 4% Other 2% Boiler data Boiler supplier Foster Wheeler Energia Oy Boiler type Bubbling fluidised bed boiler Boiler output 66 MW Steam values 23 kg/s, 61 bar, 510 C Terrain chipping is an efficient way to produce forest chips. 21

22 Cooperation for profitable biomass heat solutions Sermet IN FINLAND, the annual heating demand is high, with the share of heating representing 20 per cent of the total energy consumption. The share of district heating in space heating is 50 per cent, while the share of wood based fuels is 13 per cent of the total energy used in space heating. The goal is to increase the use of biofuels in space heating from 1.1 Mtoe in 1995 to 1.5 Mtoe in Since biofuels are not taxed when used for heat production, their use has grown significantly in district heating and CHP production. However, their share is still only 8 per cent. In the heating systems of farms in rural areas, the traditional firewood has been able to keep its central position. In residential areas modern detached houses are heated with electricity, oil or district heat. A fireplace or a stove made of heat-retaining material is used as an additional heater. The most common bioenergy solution for farms is traditional firewood, but the use of wood chips is increasing. Small industrial companies such as sawmills that need heat and steam in their production processes utilise locally available wood and bark residues in the energy production. Often they cooperate with a municipality or other partners. Sermet Innovative business model for rural areas In many rural areas, it is not viable to build a district heat network. Still, it is profitable to have a centralised heating system for heating municipal buildings such as schools, residences for the elderly and health care centres. A centralised system may utilise a boiler plant that typically has a capacity of a few hundred kilowatts. Heating entrepreneurship is an innovative way of doing small-scale energy business in rural areas. A single entrepreneur, a cooperative, a limited company or a consortium of entrepreneurs can act as a heating entrepreneur and sell heat instead of fuels. The business is usually local, the main fuel most often being wood chips. In most cases, the heating entrepreneur is responsible for the fuel supply, operation and management of the heating plant. The plant is owned by a municipality, a local energy utility or an industrial company. The fuel is supplied from the entrepreneurs own forest or other local forests, or by a local In Finland cooperation between municipalities and local wood processing companies is very common. For instance, a sawmill may produce more wood residues than needed for its own energy production. Often, the surplus fuel is burnt in the district heat boiler. Metla Delimbed small trees are suitable for burning at small boiler plants operated by heating entrepreneurs. 22

23 Manual felling and piling of small stems Felling-piling equipment Forest haulage of small trees Pile of small delimbed or undelimbed trees near forest road Heating plant Chipping sawmill or other wood processing company. Income is based on heat delivered to the client, which is usually a municipality. The goal is to automate the entire plant operation and to apply remote control for plant operations. In 2000, around 100 heating entrepreneurs operated in Finland, with the number expected to double in the near future. Transportation to heating plant Fuel to the plant is supplied by local entrepreneurs. HT Engineering VTT Wood pellets for space heating Wood pellets are a low-cost natural fuel and their usage is easily automated. They are typically compressed of sawdust and cutter shavings. No additives are used to produce them. Lignin released in the pressing process binds the wood material. Due to their consistent quality and improved energy density, pellets enable efficient transportation, successful storage and automated combustion. They are particularly suited to buildings with a boiler rating from 20 to 1,000 kw, such as small office or industrial buildings, municipal buildings and detached houses. Timberjack Vapo New innovative movable pellet boiler plant is easy to build up. The pellets are suitable for space heating in detached houses. A new mechanized method is applied for thinning young forests. The technology is based on a multifunctioning, accumulating harvester head, which collects the cleared trees quickly and efficiently. The pellets are transported to farms in large bags of up to one ton. A deposit is paid on bags, as they are recyclable. 23

24 Fuzzy logic enables smooth operation of a wood chip heating plant HEATING ENTREPRENEURSHIP has been applied successfully in Kyyjärvi, a village of 2,000 inhabitants in Central Finland. The local energy cooperative is responsible for the fuel supply as well as the operation and management of the plant, owned by the municipality of Kyyjärvi. The plant utilises mainly forest chips, which are produced from delimbed or whole trees stored at a terminal located outside the village. Chips are produced according to consumption. The heated building volume is 38,000 m 3. The quality of fuel is controlled by monitoring moisture content and bulk density. By these measurements the heating value is defined. Each member of the cooperative gets paid according to the energy content of the supplied fuel, while the municipality pays the cooperative for the heat supplied. The net profit is divided among the members of the cooperative. The plant has a grate fired boiler with a fuel drying system. That is why it is possible to burn fuel with a moisture content of over 40 per cent. Fuzzy logic is used to control the plant operations and combustion. The plant is operated by remote control with 5 persons in charge taking turns. Experiences have been so positive that the Kyyjärvi municipality has made a decision to build a second wood-fired plant with an output of 1.5 MW th. Technical data Commissioned 1999 Investment cost including 1 km DH network EUR 353,000 Annual heat output 8.6 TJ Fuel data Fuel consumption 10 TJ Fuel distribution Forest chips made from whole trees 70% delimbed trees 30% Boiler data Boiler supplier Boiler type Boiler capacity Tulostekniikka Oy Grate boiler with drying unit and controlled by fuzzy logic 1 MW th MW th VTT/Tähtikuva Delimbed small trees are stored in the terminal where they are chipped by members of the cooperative. Experiences at the Kyyjärvi plant have been so positive that the municipality has made a decision to build a second wood fired plant with an output of 1.5 MW th. The quality of fuel is controlled by monitoring moisture content and bulk density. 24

25 Pellets heat a monastery THE MONASTERY OF VALAMO in Eastern Finland is a popular Orthodox cultural centre with over 100,000 visitors annually. The Valamo Monastery offers a wide variety of services for visiting tourists. The premises of the monastery include a hotel with 200 beds, a restaurant, a winery and a shop. The heated space amounts to 40,000 m 3. The heat is produced in a boiler with a wood pellet burner. The pellets, made of cutter shavings, grinding dust and sawdust, are supplied by Vapo Oy, which operates and manages the heating station located within the monastery premises. The monastery is the sole consumer of the energy produced. Vapo Technical data Owner Valamo Monastery Commissioned 2000 Investment costs of modernisation EUR 33,640 Annual heat output 7.2 TJ Fuel data Annual pellet consumption 440 tons (7.6 TJ) Wood pellets Size 8 mm in diameter, mm in length Energy content 17.3 MJ/kg Moisture content 8 10% Ash content 0.4% Bulk density 650 kg/m 3 loose Vapo The Valamo monastery is a popular Orthodox cultural centre in Eastern Finland. The pellets are produced by Vapo Oy, a Finnish biofuel company, and delivered in an interchangeable container, hence the vehicles are not bound solely to pellet transport. Modular solution to heat production for the carpentry industry TERVOLAN SAHA JA HÖYLÄÄMÖ OY (the Tervola Sawmill and Planing Mill) located in Northern Finland is a privately owned mechanical wood processing company. Timber is sawn, dried, planed and painted at the mill. The company uses 60,000 m 3 of spruce logs and 25,000 m 3 of pine logs annually, 45,000 m 3 of which is then processed into sawn goods. During processing, some 60,000 loose m 3 of wood residue is produced and burnt each year to heat the drying plant as well as industrial and office space. The 2.2 MW th EcoFlame boiler plant, delivered in the beginning of 2002, produces heat energy for the timber drying plant with ten chambers. For fuel, the boiler plant uses wet unstripped bark and dry cutter chips. Moisture in the bark can range from 50 to 65 per cent, whereas the cutter chips contain only 15 per cent moisture. The plant can flexibly use wood residue of varying quality and moisture content. The boiler plant is built and tested at the factory before delivery, a typical delivery period being six months. Thanks to its modular structure, the plant can be transferred to other sites at small cost when necessary. There are more than 200 sawmills in operation in Finland, and their wood residues are efficiently utilised either in energy production or as raw material for the forest industry. Technical data Owner Tervolan Saha ja Höyläämö Oy Commissioned 2002 Investment costs EUR 470,000 Process heat output 2.2 MW th Annual heat output 36 TJ Fuel data Annual fuel production 39 TJ Fuel distribution Bark 80% Cutter shavings 20% Boiler data Boiler supplier Boiler type Boiler output Nakkilan Konepaja Oy EcoFlame grate boiler 2.2 MW th Nakkilan Konepaja Modular biomass fired boiler plant being transported to the customer. 25

26 Healthy space heating Heat release chart of a soapstone stove Tulikivi THERE ARE ALMOST 200,000 central house heating systems using wood fuels in Finland. The small-scale systems are typically used in detached houses or on farms. Split logs are used in 70 per cent of the systems, whilst wood pellets are burnt in some 500 boilers. However, the share of pellets is growing fast. Around 5,000 detached houses, larger buildings and farms are heated using forest chips. Almost 90 per cent of the new detached houses have a fireplace or stove made of heatretaining material. Usually, a wood stove or fireplace is used as an auxiliary heat source in one-family houses. In Finland, the number of stoves and fireplaces reaches two million, and some 6 million m 3 solid (1.1 Mtoe) of traditional firewood is burnt annually. About 25 per cent of split logs are used in sauna stoves. For chopping and splitting firewood, advanced manual and tractor-driven equipment have been developed. There is strong demand for the equipment in European markets. Soapstone, ideal material for stoves Tulikivi Nokka-Tume Effect (kw) Time from ingnition (h) Composition Talc 40 50%, Magnesite 40 50% Penninite 5 8% Properties Volume weight 3,000 kg/m 3 Melting point 1,630 1,640 C Specific heat 0.98 kj/kg C Thermal conductivity 6.4 W/mK Heat expansion /K Acid and base resistant Resistant to extreme low and high temperatures Heat from the soapstone stove is released slowly and evenly into the room. 26

27 Luxury green heat with modern stoves and fireplaces Firewood burns cleanly with an even draught and a hot flame in a masonry stove or fireplace made of soapstone or bricks. Thermal energy is quickly stored in the stove or fireplace, which releases heat slowly and evenly into the room. Flue gas emissions are minimal, thanks to the efficiency of the stove/fireplace and good firing habits. Finnish soapstone stoves/fireplaces meet the strict Austrian emission regulations. Nunnalahden Uuni A baking oven according to the Swiss requirements. 27

28 The future of energy is bioenergy BIOENERGY PLAYS a central role with global warming and the need to stabilise CO 2 emissions being made renewable energy sources more and more attractive. Finland aims to increase the use of bioenergy sources by 50 per cent by This target is demanding Finland being one of the leading bioenergy countries among the industrialised world, the share of bioenergy in the total energy consumption is already as high as 20 per cent. In addition to environmental considerations, there is another aspect; the use of bioenergy will be important for the local economy in sparsely populated rural areas. Fuel procurement especially can boost employment. In Finland, the development of energy technology has been made the cornerstone for future energy and climate change policies. R&D is regarded the most efficient way to achieve solutions that are of great importance to environment and economy in the long run as well. The Finnish bioenergy expertise and know-how provide a solid base for the advanced technological solutions. Most certainly, they will have applications in the countries where reduction of CO 2 emissions will be crucial. The most challenging goal in increasing the use of bioenergy and in the development of technologies is to minimise costs of fuel procurement. Sustainable forestry with emphasis on the entire forest ecosystem and biological diversity as well as a sustainable energy economy focusing on environmental solutions in fuel harvesting and transport will be the challenges in the future. Roxon Development of combined heat and power production (CHP) VTT CHP products Electricity Process heat District heat Clean water District cooling Hydrogen CHP technologies Power-toheat ratio Back pressure turbine Combined cycle plants Heat storage Micro-plants (microturbine, fuel cell...) Hydrogen Cold storage storage Conventional CHP Micro-CHP The share of district heating CHP electricity in Finland 0.1% 11% 12% 14% 16% 28% Past and anticipated future development of CHP technology. The share of total CHP electricity in Finland 28% 28% 28% 31% 37% 50% 28

29 More electricity with distributed energy technologies Simultaneous production of electricity and heat boosts the profitability of small-scale power plants. The benefits achieved by the CHP make them economically attractive in the electricity market, especially as the new EU directive for electricity production by RES takes force. Gasification enables use of niche biofuels Gasification is one of the promising future technologies. The primary advantage of gasification is economic: it enables cheaper fuels like wood residues to be substituted for expensive fossil fuels. Gasification of wet biofuels presents no major technological problem. The most effective solution for small-scale power production is to combine a gasifier with a combustion engine. Commercial gasifiers are available in a large range of sizes and types. They run on a variety of fuels, like wood, bark, charcoal, straw, coconut shells and rice husks. Power output is determined by the economical supply of biofuel. Turku Energia/Suomen Ilmakuva Oy Pyrolysis oil for heat and power production Liquid biofuels have the potential to reduce environmental and economic impacts of energy production. They provide advantages over other biomass fuels in transportation costs, ease of handling and economic savings. In Finland, they especially reduce dependence on fuel oil and increase fuel diversity in energy production. 29

30 Electricity is generated in eversmaller CHP units: general trend (line) for the minimum competitive size and the existing plants (symbols) in Finland. In Finland, Fortum Oil and Gas, Vapo and VTT have developed pyrolysis oil process concepts for sawdust and forest residue applications. The first pilot plant started production of pyrolysis oil in late 2001 and the commercial size production plant should be completed in Recent years have seen significant improvements in production quality and stability. Power, MW Gas turbine Development of competitive CHP plant size Steam turbines Diesel engines Gasifier & engine Steam engines Diesel engines Organig Rankine cycle turbines Gas engines Micro turbines Stirling engines Fuel cells Pyrolysis oil is a new biofuel product ideal as a substitute for fuel oil and for future diesel power applications. Results of R&D begun in 1998 to study pyrolysis oil production and utilisation now indicate that local biomass resources can be effectively processed into a liquid product, pyrolysis oil. Pyrolysis oil offers signigicant advantages: it is easy to store and transport, suitable for combustion in small-scale applications, highly efficient and costeffective. Moreover, it produces low emissions when burnt. Challenges still to overcome include improving the heating value of pyrolysis oil, at the moment only half that of petroleum products, and making pyrolysis oil miscible with petroleum products. R&D focuses on demonstrations In Finland, Tekes, the National Technology Agency of Finland acts as the main financing and expert organisation for technological R&D. Tekes is also an excellent information channel for organisations looking for a Finnish partner in bioenergy. The Tekes technology programmes are used to promote development in specific sectors of technology or industry and to pass on results of the research work to business in an efficient way. Programmes have Residential heat and power Fortum VTT 30

31 VTT VTT and Condens Oy have developed a new type of fixed bed gasifier, which is based on forced fuel flow and consequently allows the use of low-bulk-density fibrous biomass residues. This gasifier is a combination of the updraft and co-current gasification technologies. proved to be an effective form of cooperation and networking for companies and the research sector. Thanks to the programmes several new successful products and processes have been developed. Finnish bioenergy R&D will focus on demonstrations and commercialisation of innovative technologies in the next few years. Further intensive R&D efforts will be continued on the following areas: Integrated harvesting and transport concepts, techniques and practices for forest fuels Fluidised bed combustion with higher steam values Multifuel energy production concepts CHP and small-scale cogeneration (less than 5 MWe) Fluidised bed gasification of biomass or recovered fuel together with pulverised coal fired boilers Advanced liquid biofuels concepts, their production and combustion in boilers and engines Pulp and sawmill by-products-based power and bio products, new concepts and boilers for spent cooking liquors and chemical recovery 31

32 Bioenergy contacts in Finland Tekes, the National Technology Agency of Finland Financing for applied and industrial R&D P.O. Box 69, FIN HELSINKI Tel , fax The Ministry of Trade and Industry, Energy Department Energy administration P.O. Box 32, FIN VALTIONEUVOSTO Tel , fax The Ministry of Agriculture and Forestry Administration of forestry and agriculture P.O. Box 30, FIN VALTIONEUVOSTO Tel , fax Motiva Oy Information for energy efficiency and renewable energy sources P.O. Box 489, FIN HELSINKI Tel , fax A S S O C I A T I O N S The Bioenergy Association of Finland (FINBIO ry) P.O. Box 27, FIN JYVÄSKYLÄ Tel , fax Finnish Energy Industries Federation Finergy P.O. Box 21, FIN HELSINKI Tel , fax Finnish Biogas Centre P.O. Box 1173, FIN HELSINKI Finnish District Heating Association Frederikinkatu 61, FIN HELSINKI Tel , fax Finnish Forest Industries Federation P.O. Box 336, FIN HELSINKI Tel , fax Finnish Electricity Association - SENER P.O. Box 100, FIN HELSINKI Tel , fax Wood Energy Association Soidinkuja 4, FIN HELSINKI Tel ,fax R E S E A R C H I N S T I T U T E S Agricultural Research Centre of Finland Institute of Crop and Soil Science Energy crops FIN JOKIOINEN Tel , fax European Forest Institute Forestry Science Torikatu 34, FIN JOENSUU Tel , fax Finnish Forest Research Institute (METLA) Forestry Science Unioninkatu 40 A, FIN HELSINKI Tel , fax Metsäteho Oy Wood procurement and production P.O. Box 194, FIN HELSINKI Tel , fax Technical Research Centre of Finland, VTT Renewable energy sources P.O. Box 1601, FIN VTT, (Espoo) Tel , fax TTS-Institute Wood fuel production and small-scale combustion technologies, energy crops P.O. Box 13, FIN RAJAMÄKI Tel , fax

33 U N I V E R S I T I E S University of Helsinki Agricultural and forestry sciences Energy crops P.O. Box 62, FIN HELSINGIN YLIOPISTO Tel , fax Helsinki University of Technology Laboratory of Energy Economics and Power Plant Engineering Combustion and gasification technologies P.O. Box 4100, FIN TKK Tel , fax University of Jyväskylä Renewable energy sources P.O. Box 35, FIN JYVÄSKYLÄ Tel , fax Lappeenranta University of Technology Energy technologies and economics P.O.Box 20, FIN LAPPEENRANTA Tel , fax Tampere University of Technology Combustion and modelling technologies P.O. Box 527, FIN TAMPERE Tel , fax University of Joensuu Forestry science P.O. Box 111, FIN JOENSUU Tel , fax University of Oulu Peat, wood and agrobiomass production P.O. Box 7300, FIN OULUN YLIOPISTO Tel , fax Åbo Akademi University Combustion and gasification technologies Piispankatu 8, FIN TURKU Tel , fax P O L Y T E C H N I C S Jyväskylä Polytechnic School of Natural Resources Uuraistentie 240 B, FIN TARVAALA Tel , fax Kymenlaakso Polytechnic P.O. Box 13, FIN KOTKA Tel , fax Mikkeli Polytechnic P.O.Box 181, FIN MIKKELI Tel , fax North Karelia Polytechnic Väisälänkatu 4, FIN JOENSUU Tel , fax Satakunta Polytechnic Tiedepuisto 3, FIN PORI Tel , fax power provides access to contact information of almost 200 Finnish bioenergy companies. information on Finnish science and technology 33

34 Definitions Bioenergy Biofuel Biomass Wood based fuels Wood fuel Forest wood Forest residues Recycled wood fuels Refined fuel Pellet Pyrolysis oil Industrial wood Recovered fuel (REF) Peat Gigajoule (GJ) Megawatt hour (MWh) toe Mtoe Bioenergy refers to energy derived from biofuel. (= biomass fuel) Fuel produced from biomass. The fuel may have undergone mechanical, chemical or biological processing or conversion or it may have had a previous use. Biofuel refers to solid and liquid biomass-derived fuels. Refers to the biodegradable fraction of products, waste and residues from agriculture (including vegetal and animal substances) and forestry and related industries, as well as the biodegradable fraction of industrial and municipal waste. EU Directive 2001/77/EC. Include forest wood, industrial wood as well as wood fuels recovered after chemical treatment (e.g. black liquor) and recycled wood fuels. Biofuel from tree biomass, which has not undergone a chemical process. Wood fuel where the raw material has not previously had another use. Forest fuel is taken from the forest and processed directly for energy use. Forest fuels can be fuels from logging and thinnings. Wood residues consisting of branches, tree tops, brushwood and small trees not harvested or removed from logging sites in commercial wood stands as well as material resulting from forest management operations. Recycled wood fuels include post-society wood fuels like demolition wood, wood casing and other waste wood. Biofuel which has been treated mechanically or chemically to make its properties homogenous. Pellets, briquettes and pyrolysis oil, for example are refined fuels. Fuel in the form of short cylindrical or spherical units. Fuel pellets are usually manufactured from cutter shavings, dried sawdust and powder. Pellets are usually 8 12 mm in diameter and mm in length, with moisture content of less than 10 per cent. In flash pyrolysis, wood (moisture content less than 10 per cent) is heated up to C in a very short time. The organic particles are transformed into gas that is then converted to a liquid (oil). Generally, the bio-oil yield is about 70 per cent wt. Industrial residues comprise various types of solid wood residues from the forest industry such as sawdust, bark, cutter shavings, slabs, grinding dust etc. Fuels made of pre-sorted municipal, industrial, construction and demolition waste, excluding industrial waste utilised by industry itself in energy production. A material formed by decomposition of dead plant parts under very moist conditions. Peat material is thus of biological origin. It is continuously formed in wetlands and decomposed in varying degrees by biological and chemical processes with limited oxygen access. Peat is a local, indigenous, solid fuel, which is used as milled or sod peat. Unit referring to heat, 1 TJ = 1000 GJ Unit referring to electricity, 1 MWh = 3.6 GJ, 1 TWh = 1000 GWh tonne of oil equivalent, 1 toe = MWh = GJ million tonnes of oil equivalent 1 m 3 solid unit referring to wood as solid cubic meter 1 m 3 solid 2 MWh (7.2 GJ) 2.5 m 3 loose 1 m 3 loose/bulk unit referring to wood as loose cubic meter, 1 m 3 loose MWh ( GJ) 34

35 GROWING POWER Advanced solutions for bioenergy technology from Finland Tekes, the National Technology Agency Kyllikinportti 2, P.O. Box 69, FIN Helsinki, Finland Tel Fax February 2002