Biomass for energy in Poland

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1 Biomass for energy in Poland Krzysztof Urbaniec, Robert Grabarczyk CERED Centre of Excellence Warsaw University of Technology - Plock Campus, Plock, Poland e mail: gstku@mbox.pw.edu.pl Grzegorz Wisniewski Institute of Renewable Energy, Warsaw, Poland gwisniewski@ieo.pl ABSTRACT The Polish resources of renewable energy, that is, energy amount potentially available from renewable sources, are currently estimated at about TJ per year. In this imaginary energy stream, the share of biomass including energy crops, dry and wet agro-waste, and forestry waste is more than a half. In the national strategy of energy supply until 2030, a considerably increased share of renewable energy in the supply of final energy, 16.6% as opposed to 7.7% at present, is foreseen. This can be achieved mainly by improving the utilisation of biomass resources and mainly energy crops, adding also improved utilisation of wind energy. It is generally agreed that the system encompassing large-scale land use for energy crops and the associated conversion of biomass energy to heat and power has to satisfy three basic requirements: sustainable biomass production, economic viability and high energy efficiency. 1. INTRODUCTION To meet the double challenge of increasing national energy demand and emission restrictions resulting from international obligations and in particular those agreed within the European Union, the energy sector in Poland faces the necessity of working out a new development strategy. The strategy must be compatible with the governmental energy policy in which the following priorities are set [1]: Improved energy efficiency, Safety of national energy supply, Increased share of renewable energy in the national energy supply, Development of competitive energy markets, Reduction of the environmental impact of energy sector. The priorities are to a large extent interrelated. Improved energy efficiency reduces the demand for primary energy thus positively affecting the safety of energy supply and reducing the environmental impact. Similarly, increased supply of renewable energy contributes to improved national energy safety by partly substituting imported gas and oil, and reduces the environmental impact. If combined with the introduction of modern energy technologies and in particular distributed heat and power generation, it also facilitates improvements in the energy efficiency and becomes an important factor in the development of energy markets. In the present paper, the focus is on biomass as a renewable energy resource and its possible role in the strategy of development of the Polish energy sector. Potential biomass resources and most promising ways to increase their availability and intensify their utilisation for heat and power

2 generation are reviewed. It is shown that a sustainable energy strategy must be coordinated with the strategies of development of other sectors and in particular agriculture. 2. RENEWABLE ENERGY TODAY The consumption of primary energy in Poland is about 100 Mt oil equivalent, or TJ, per year. Its distribution between different energy carriers is shown in Fig. 1a. The dominating role of coal and a modest share of renewable energy are symptoms of structural problems in the country s energy supply resulting in a high level of carbon dioxide emission. Aiming at the emission reduction in accordance with international agreements and being aware of the necessity to increase the role of renewable energy, politicians and professionals are involved in discussions on the availability of renewables and the ways to optimise their use. The discussions are lively, estimates of availability are differentiated and conflicting views are expressed regarding the future course of action. gas 12.6 renew ables 5 coal 44.8 oil 24.8 lignite 12.8 Fig. 1. Structure of primary energy consumption in Poland according to statistics Widely recognised data on the potential resources of renewable energy realistically available up to 2020 and the level of their utilisation in 2006 are summarised in Tab. 1. The potential resources are understood as the energy amount available for economically viable utilisation, on the annual basis. As can be seen, biomass constitutes more than a half of realistically estimated Polish resources of renewable energy. At present, this potential is utilised for heat and power generation, and production of transportation fuels, to about 30%. Another important renewable resource is wind energy whose potential, estimated at more than 1/3 of the renewable total, is presently utilised to less than 1%. Solar energy is less significant, while geothermal energy and hydropower are of marginal importance only. Table 1. Potential medium term resources of renewable energy and their use in Poland (after [2]) Potential resource TJ/year Utilisation of potential in 2006 TJ/year % Biomass Wind Solar Hydro Geothermal TOTAL To illustrate conflicting views on the magnitude of renewable energy resources, it can be mentioned that earlier estimates of disponible geothermal energy, based on geological surveys,

3 have been much higher up to TJ/year. However, a large part of geothermal energy is found at 2-3 km depth in salty water at a temperature below 90 o C. In view of technologies currently available for its utilisation, it cannot be classified as a resource of potential economic viability in medium term. Conflicting views can also be demonstrated on the example of wind energy potential. The estimate given in Tab. 1 is questioned by the coal & lignite based power industry. Referring to the requirements of safe operation of the national power grid, it is claimed that power production in wind turbines must be limited to a small fraction of power production in thermal power plants about TJ/year at present. 3. BIOMASS RESOURCES Assuming that biomass available for energy generation or biofuel production can be divided into dry agro-waste, wet agro-waste, fuel wood & forestry waste, and energy crops, its potential resources and utilisation in 2006 are illustrated by the data given in Tab. 2. Dry waste including straw has now a permanent place in the fuel market and its economically viable potential is utilised almost completely. The physical availability of dry waste is much larger, but its utilisation is limited by the geographical distribution and unfavourable structure of energy prices. Fuel wood and forestry waste constitute a special case: utilisation seems to be high but the definition of potential resource, arbitrarily set by forestry administration, is now questioned. As it turns out that over-all wood resources in state-owned forests have been increased in recent years, this definition may be changed in the future, possibly allowing increased use of this biomass type. Large margins of possible increase in the generation of clean energy can be seen in the resources of wet biomass waste and energy crops. Wet biomass waste is available in significant amounts but up to now mainly converted to fertiliser or remaining largely unused. It is recognised as a potential raw material for fermentative conversion to biogas, but this path of utilisation is marginal so far because biogas production in Poland is only beginning and no other conversion technologies are ripe for large-scale economic applications. An even larger expansion potential can be attributed to energy crops where the situation is much more complex and differentiated between various crop types. Table 2. Potential biomass resources in Poland (after [2]) Potential resource Utilisation of potential TJ/year TJ/year % Dry agro-waste Wet agro-waste Fuel wood Energy crops including: lignocellulosics sugar/starch rape silage corn BIOMASS TOTAL There is a considerable interest among farmers for growing sugar-containing and starchy crops including sugar beet, potato and wheat for further processing to bioethanol. In recent years, the availability of those crops for biofuel production has been hindered by unstable market conditions and competition from food and feed industries. For several years in a row, rape seed

4 growing for biodiesel production has been gaining popularity. However, this branch of agrobusiness is now under a question mark resulting from increasing, together with the debate around EU climate package and new RES directive, doubts about its sustainability. Very much discussed but still awaiting large-scale commercialisation are lignocellulosic crops including willow, multiflora rose, miscanthus, Virginia fanpetals etc. produced as solid fuel or raw material for further conversion to liquid fuels, and corn produced for ensilage and further processing to biogas. The main limiting factors, especially for perennial plants, are: a high cost of starting up biomass production, and unstable market conditions making long-term business planning very difficult. There is a growing awareness of the need for creating a well organised market for biomass from energy crops. Up to now most of state support for energy crops was used for rape seed production, especially in large scale farms. The present scheme of support to energy crop growers has proved to be inefficient as it does not reach farmers who want to establish new plantations of perennial crops and achieve a stable position as long-term biomass suppliers. The farmers can be expected to dedicate their land to energy crops growing only if biomass sales to energy companies and agrorefineries are guaranteed at price levels that ensure a profit higher than that attainable when producing cereals on the same land. As a possible solution to this problem, the concept is discussed of a system of long-term contracts for biomass supply at prices flexibly modulated after variable market situation. To implement such a system, initiatives and engagement of govermental agencies responsible for monitoring and regulation of the energy market and agricultural markets will be necessary. 4. RENEWABLE ENERGY IN 2030 According to a document recently published by the Polish Department of Energy [1] in response to the governmental prorities of the energy policy explained in Section 1 above, the consumption of primary energy expected in 2030 is about 114 Mt oil equivalent, or TJ, per year. Its distribution between different energy carriers is shown in Fig. 2a; the expected share of renewable energy is about 13% (equivalent to 16.6 % in the final energy consumption, as compared to 7.7% at present). The forecast is based on the assumption of economic slowdown (annual growth rate %) in the period and accelerated economic growth (annual rate about 5%) after 2012; the energy intensity of Gross Domestic Product in the forecast period is expected to decrease by a factor of 2.7. a) b) renewables 13 other 1.6 nuclear 6.6 coal 26.1 renewables 25.4 coal 19.4 lignite 3 gas 15.9 oil 27.2 lignite 9.6 gas 32.2 oil 20 Fig. 2. Expected structure of primary energy consumption in Poland in 2030: a) forecast by the Department of Energy (after [1]), b) study by Greenpeace Poland (after [3]). It is interesting to compare the official forecast with the predictions given in a report by Greenpeace Poland [3], where a stable economic growth at a rate close to 5% (current economic crisis neglected) and a reduction of energy intensity of GDP by a factor of 2.1 have been

5 assumed. In Greenpeace scenario based on the assumption of highest priority attributed to rational energy use and clean energy, the consumption of primary energy in 2030 is estimated at 106 Mt oil equivalent, or TJ, per year and the predicted share of renewable energy is 25.9% (see also Fig. 2b). The latter figure is equivalent to 28.4% renewables in the final energy consumption. It is widely believed that the period of 20 years between 2010 and 2030 is sufficiently long to make it possible to implement large-scale action programs and apply various measures aimed at restructuring of the Polish energy sector. However, even with the seemingly modest goal of 12.6% renewables in the future supply of primary energy, it is going to be a formidable task to increase the consumption of renewable energy from the present level of about TJ/year to the expected 2030 level of nearly TJ/year. Up to now, the governmental initiatives have been restricted to the production of biofuels and in particular liquid ones for transportation, and prove to be a limited success only. It seems that the quantitative goals set for 2010, that is, 7.5% share of renewables in the country s gross energy consumption, 7.5% share of renewables in the consumption of electrical energy and 5.75% share of biofuels in the transportation fuel market, will be very difficult to achieve [1]. It is now generally agreed that in any future governmental initiatives, it is necessary to pay more attention to specific problems of distributed energy generation. Heat and power production on the basis of renewable resources requires the application of small energy conversion units located close to heat and power users. Planning, financing and managing the development of distributed energy generation units implies the need for a profound change in relation to established development practices based on the assumption of large centralised heat and power sources. Firstly, local authorities have to engage in the identification of energy demand and disponible energy resources in the areas of their responsibility, and the planning of local capabilities of energy generation and distribution. Although the Polish energy law of 1997 includes the obligation of energy planning on the community level, it has now been recognised that the established planning practices are insufficient and must be improved, starting from the necessary corrections in the energy law. A relevant provision concerning the planned amendment to the energy law is included in the new draft of energy policy and it is likely that the European Commission will include a similar advice to the government in the coming guideline for national renewable energy action plan up to Secondly, a legal framework is needed for smooth integration of distributed energy generation units with energy distribution systems. The range of problems now seen in the power grid and requiring an urgent solution includes definition of technical requirements for connecting small power generation units to power distribution networks, principles of price setting for power supplied from small units, and methods of accounting power supplied vs. power consumed by operators of small units. 5. BIOMASS FOR ENERGY IN 2030 Bearing in mind the structure of potential renewable resources presented in Section 2 above, the postulated expansion of renewables will in the first place require working out and implementing a concerted action program aimed at increasing the availability of biomass, an mainly lignocellulosic energy crops, for heat and power generation generation and conversion to transportation fuels. As can be seen in Tab. 3, the prospects of increasing the output of biomass for energy in Poland, evaluated on the basis of arable land area per capita, are relatively good. Serious estimates of arable land area potentially available for the production of energy crops are widely differentiated ranging from 1 to more than 3 million ha [2, 4]. Taking the constraints of domestic food

6 production and nature preservation into account, the lower limit seems to be the most realistic estimate. Table 3. Arable land area per capita in selected EU countries (after [2]). Country Area (ha) Country Area (ha) France 0.47 Poland 0.42 Germany 0.21 Spain 0.59 Ireland* 1.00 The Netherlands* 0.12 Italy 0.25 United Kingdom 0.28 */ EU high, respectively EU low In view of the necessary investments in the infrastructure for biomass production and logistics, the question is not about just using the available land, but about using it wisely. Three main requirements to be satisfied are: sustainability of biomass production, economic viability of biomass production and conversion, and a high energy efficiency. Obviously, the necessary action program must include agricultural components aimed at choosing right locations for energy crops growing and selecting optimal crop varieties. However, equally important is the choice of suitable biomass conversion strategies and matching energy technologies. On top of that, the progress of implementation of the action program will have to be monitored with respect to its influence on the security of food supply and the environmental impact of agricultural production. Regarding the location of growing areas for lignocellulosic crops, a problem to reckon with is the availability of water necessary for achieving a high biomass yield. Among the different Polish regions, the fastest expansion of energy crop growing has been seen in the western part of central Poland. However, this is also the region of lowest annual rainfall amount and therefore local conditions for achieving a high yield are poor. This indicates the need for promoting energy crops in the northern (excluding coastal areas) and south-eastern parts of the country where more favourable climatic conditions coincide with the local deficit of other renewable energy resources. As the different regions of Poland are widely differentiated with respect to climatic conditions, soil quality and prospective local demand for biomass, a wide knowledge base and expert skill are required for the right selection of crop species and varieties for new plantations. It is believed that the Polish institutions of agricultural research and advisory services have now accumulated the necessary expertise. Technologies of crop production and biological characteristics of different crops have been extensively studied making it also possible to determine their economic characteristics and suitability for various growing locations. To exemplify the knowledge based on a combination of experience and results of agricultural research, it is known that the Scandinavian varieties of willow popular among Polish willow growers cannot be regarded as optimal because of their susceptibility to diseases affecting Polish plantations. As a result of breeding research, more resistant willow varieties are now available to interested growers. Research has shown as well that from agricultural point of view grasses and miscanthus type crops may in many areas be more suitable for growing than willow, contrary to current expectation of the energy and power industry. Regarding biomass conversion strategies and compatible energy technologies, research and development activities are under way and practical experience is gathered. However, in view of a changing economic environment and a constant stream of technological innovations, this seems to be an area of permanent change necessitating a flexible and continuously updated approach. Although the decisive role of lifecycle-type approach is is widely agreed, the general mood is

7 that practical choices should as much as possible follow the line of high energy efficiency and low cost of carbon dioxide reduction. Bearing this in mind and restricting the attention to proven technologies, direct use of biomass should generally be preferred to the production of liquid biofuels. The current list of suitable energy conversion technologies, in the order of preference, is following: Co-firing in large combined heat and power (CHP) plants, Firing in small dedicated CHP units, Co-firing in large power plants (rather short term option only), Firing in small dedicated power plants. It is an open question to what extent and when should this list be updated in the coming decades. Apart from numerous development activities devoted to commercial implementation of known technologies [5], Polish researchers are involved in a number of national and international projects aimed at working out new, sustainable and economically viable technologies of biomass conversion to clean energy carriers [6, 7]. 6. CONCLUDING REMARKS The discrepancy between potential availability of biomass and the present level of its utilisation for supplying clean energy to Polish consumers is very large. By increasing the level of utilisation in a sustainable way, meaningful ecological, economic and social effects can be attained. This requires political support as it will be necessary to build up legal and administrative infrastructure for a positive development and set up and implement a largescale action program encompassing adjustments in the established practices of agricultural and industrial production, and environment protection. The professional community has already identified the main lines of action and critical problems to be solved. Still missing is the public awareness from which the necessary political support can be derived. REFERENCES 1. Polish Department of Energy, Energy Policy of Poland until 2030 (in Polish), Draft Position Paper, Warsaw, Wisniewski G., Contribution of biomass to the implementation of EU energy and climate package 3 20% in Poland (in Polish), Proceedings of the Conference Role of biomass in energy generation, Bialowieza, Energy [r]evolution for Poland. Long-term scenario of supplying clean energy carriers (in Polish). Report from Greenpeace Poland, Warsaw, Faber A., Energy crops as a potential threat to the food market and environment (in Polish), Proceedings of the Conference Role of biomass in energy generation, Bialowieza, (in Polish) Urbaniec K., Grabarczyk R., Raw materials for fermentative hydrogen production. Journal of Cleaner Production, Vol. 17, No. 10, pp , ACKNOWLEDGEMENTS Support of the European Commission under contract HYVOLUTION and support in the framework of European Social Fund through Warsaw University of Technology Development Programme, are gratefully acknowledged.