A NEW DECISION SUPPORT TOOL FOR BIOMASS ENERGY TECHNOLOGY PROJECTS IN EUROPE. Dr Ralph Horne* Centre for Design at RMIT University, URL: http://www.cfd.rmit.edu.au E-mail:
[email protected] *Note: While Ralph Horne is Project Co-ordinator of the BIOMITRE project and the sole author of this paper, acknowledgements are due also to the project partners, without whom the project could not have reached its current final stages: N. D. Mortimer, M. A. Eslayed, R. Matthews, B. Schlamadinger, E. Bjorkland, L. Gustavsson, P-A. Vikman, S. Soimakallio, A. P. C. Faaij, and J. van Dam. Any errors or omissions within this paper are, however, solely the responsibility of the author. The BIOMITRE project was undertaken with funding from the Directorate-General for Energy and Transport of the European Commission (EC) and co-funding support from the International Energy Agency (IEA) Task 38.
ABSTRACT
Diverse biomass energy technologies present considerable potential for the large-scale exploitation of renewable energy sources. Additionally, these technologies offer significant prospects for reducing greenhouse gas (GHG) emissions which are associated with global climate change. However, in order to assist the promotion of these important technologies, it is essential that there is a wide understanding and appreciation of their relative GHG emissions benefits. In order to address this, a software tool has recently been developed as part of the "BIOmassbased Climate Change MITigation through Renewable Energy" or BIOMITRE Project, funded by the European Commission, with support from OECD’s International Energy Agency Task 38. The project was designed to allow production of a software tool which provides a standard means of analysing the GHG balance and emissions-saving costeffectiveness of biomass energy technologies. The BIOMITRE Tool is presented and described, including the main elements of the relevant technologies; production (cultivation, harvesting, recovery. etc.), processing (chipping, pelletisation, baling, etc.), transportation (by road, rail, waterways, etc.), conversion (direct combustion, co-firing, gasification, pyrolysis, digestion, etc.) and end-product utilisation (heat, power, combined heat and power, liquid biofuels, etc.). Discussion is also included on the current considerable activity in the commercialisation of biomass technologies, and the extent to which the BIOMITRE Tool may assist the widespread propagation of biomass energy technologies as a cost-effective means of providing commercial renewable energy supplies which mitigate global climate change through GHG emissions savings. Key features of the Tool are also evaluated, including transparency, standardisation, modularity, data sources, case studies, and related issues, along with an assessment of future potential developments and applications.
Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
1
Keywords: greenhouse gas balances, software tool, biomass, cost-effectiveness 1.
BACKGROUND
In Europe, the rapid development and commercialisation of biomass energy technologies is currently being driven primarily by the need to reduce carbon dioxide emissions from the burning of fossil fuels. Within this context, it has been recognised by many stakeholders in this process, that a reliable and accurate means of measuring the total emissions associated with each technology is an important requirement, to allow an agreed estimate of the fossil carbon savings to be identified. Indeed, this becomes a critical issue when decisions over commercial biomass energy technology developments are partly dependent upon tax incentives and/or (certified) future carbon credits in a carbon trading system. For such sophisticated regulatory mechanisms which encourage each technology in proportion to the carbon saved, it is clearly of utmost importance to developers, investors, regulators, and society as a whole, that this carbon saving is calculated in an agreed, open, transparent and reliable manner. The general methodology is agreed upon, using the established framework for LCA specified by the International Standard ISO14040 series. In ISO14041 and ISO14042, the basic principles, definitions, conventions and methods of calculation are summarised. Against this background, various studies comparing the energy and environmental aspects of different biomass energy technologies options exist (for example, [1-3]), all of which broadly conform to LCA principles, but all of which differ and tend to be country-specific, adopt a unique reporting structure, and therefore provide results which should not be compared directly. It is possible to review the extent to which studies conform to LCA principles, however, within this there are potentially wide variations in interpretation and application. For example, while the framework requires studies to be transparent, it does not stipulate how transparent. No study is entirely transparent, as, for example, this would require it to include all reference sources in full in appendices. However, few studies show in detail how calculations are achieved and data sources are rarely itemised for each datum. Hence, there are a range of problems associated with standard methodology development and application. A major research project funded by the European Commission has been attempting to address these issues, by developing a software tool incorporating a standard and transparent methodological approach, and the development of this tool is the main subject of the current paper. One issue is of particular concern - that of allocation. It is necessary to apply allocation whenever a technology being assessed involves the generation of co-products and by-products. For example, rape straw, rape meal and glycerol are produced during the production of biodiesel from oilseed rape. Since these are useful products, some of the fossil carbon (or, more accurately, greenhouse gas emissions) must be allocated in a logical way between the main product, the transport biofuel, and the associated co- and by-products. If allocation were not applied, then the main product carries the entire burden of greenhouse gas emissions, and the co- and by-products carry none of these implications. Hence, in situations where decisions are made on the basis of greenhouse gas emissions savings, such co- and byproducts would incorrectly appear in a favourable light compared with alternative products. Options for allocation are set out in the International Standard ISO14040 Series, and appropriate choices depend upon the technology, the co- and/or by-products involved and their uses, and, perhaps most importantly, the specific question being asked of the exercise. The ISO14040 series is designed as a generic framework for LCA, and a more detailed and specific method is therefore required to assist specifically with calculating greenhouse gas emissions savings for biomass energy technologies. However, the danger of developing a more prescriptive and specific method is that it raises the possibility of producing standard results which may not be accurate, but may simply contain the same standard errors of method. Hence, any standard method should be theoretically and practically valid. 2.
AIMS AND OBJECTIVES
The "BIOmass-based Climate Change MITigation through Renewable Energy" or BIOMITRE Project (European Commission Contract Reference Number NNE5-00069-2002) provides for the production of a new Software Tool (available in downloadable form from www.joanneum.at/biomitre/softwaretool). In order to assist the promotion of biomass energy technologies, it is essential that there is a wide understanding and appreciation of their GHG emissions benefits - hence, this software tool, based on a standard methodology. The aim of this tool is to provide a standard means of analysing the GHG balance and emissions-saving cost-effectiveness of biomass energy technologies. The aim of this paper is to document the development and use of the BIOMITRE Software Tool, including associated issues, intended applications and potential shortcomings. In order to achieve this aim, the following objectives have been set: • to review the general approach recommended in relevant ISO standards, 2 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
• to summarise the range of biomass energy technologies studies, and the issues and problems with existing studies and approaches to greenhouse gas and cost-effectiveness calculations, • to compare, discuss and test the implications of issues and problems with existing studies and the consequent requirements of the BIOMITRE Tool, • to present the standard method used in the BIOMITRE Tool and outline its use, • to draw conclusions and present potential areas for further work. 3.
GREENHOUSE GAS ACCOUNTING FOR BIOMASS ENERGY PROJECTS
The general approach to energy and greenhouse gas (GHG) accounting is outlined below, including current guidance and standards, how they apply in the case of biomass energy technologies, the concept of net emissions, and the key issue of allocation options. 3.1 Guidance and Standards The practical use of LCA has been considerably enhanced by the adoption of an official framework in the form of the International Standard ISO 14040 series [4-8]. From this framework, which establishes definitions and conventions and presents advice on methods of calculation, it is clear that LCA involves six major stages: 1. Goal and scope definition 2. Life cycle inventory analysis 3. Life cycle impact assessment 4. Life cycle interpretation 5. Reporting 6. Critical review. Regarding goal and scope, here we are concerned with greenhouse gas emissions savings of biomass energy technologies compared to typical fossil alternatives. Life cycle inventory analysis usually requires considerable data collection and analysis, although for current purposes the parameters can be simplified to those which may affect greenhouse gas emissions (both in the reference fossil fuel case and in the biomass energy technology being studied). Life cycle impact assessment and life cycle interpretation are unnecessary for the current work, since it is concerned only with comparing total greenhouse gas emissions (in equivalent global climate change terms), although reporting and critical reviewing do need careful consideration. 3.2 Application to Biomass Energy Chains LCA adopts a systems approach, where the process chain is treated as a sequence of sub-systems that exchange inputs and outputs. A simple, general process chain diagram is sufficient to illustrate this approach when applied to biomass energy technologies (see Fig. 1). Hence, the application of systems boundaries might, at first, seem like a self-evident and simple exercise. However, in an industrial economy, there are links, immediately or remotely, between any one activity and all the other activities in the economy. Hence, when preparing a life cycle inventory, it is, in theory, necessary to trace all these connections in order to account for all the accumulated inputs and outputs.
Source Material ↓ PROVISION ↓ TRANSPORTATION ↓ Feedstock Material ↓ PROCESSING ↓ Final Product
Fig. 1. General Process Chain Diagram for Biomass Energy Technologies [2] 3 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
For example, primary energy is consumed as a result of the fuels and electricity used in the factories which manufacture agricultural equipment for use in growing biomass energy crops. Such factories also require raw materials, such as steel, which itself involves the consumption of further primary energy through the fuels and electricity used in the steelworks. Fortunately, successive contributions diminish in relative magnitude, although this still needs to be demonstrated. Looking down the process chain, there are invariably by- and co-products being produced at different points in the chain. For example, in the case of Bioethanol, production from wheat, straw is produced as a useful by-product in the field, whereas distillers dry grains are produced as a useful by-product in the ethanol plant. Any allocation of greenhouse gas emissions to straw will therefore only affect the inputs into the crop cultivation and harvesting, whereas allocation to distillers dry grains would affect inputs up to the point in processing where this by-product is produced. Linked to the process chain, one aspect of GHG analysis which needs to be considered for biomass energy production is the matter of reference systems, which are used to determine credits for alternative activities that are avoided or displaced. For example, the land which is used for growing a biomass energy crop could be used for another purpose, or maintained as fallow. When selecting an appropriate reference system, it is important to use that which is most likely in practice and which reflects current economic reality - which varies temporally and spatially. 3.3 Range of Biomass Energy Technologies It is important to note the range of biomass energy technologies, as this indicates the scope of technologies that the software tool must be designed for. The biofuels study for the Energy Technology Support Unit in the UK [2] identified the following 18 separate options for consideration, based on consultation with scoping advisors: • • • • • • • • •
biodiesel from oilseed rape and waste oils (2 options) combined heat and power (large scale with an industrial load) by combustion of wood chip from forestry residues (large scale) combined heat and power (small scale) by gasification of wood chip from short rotation coppice electricity (large scale) by combustion of miscanthus electricity (large scale) by combustion of straw electricity by combustion, gasification or pyrolysis of wood chip from forestry residues (large scale) or short rotation coppice (6 options) bioethanol from lignocellulosics, sugar beet and wheat (3 options) heat (small scale) by combustion of wood chip from forestry residues (large scale) and woodland residues (small scale), and rapeseed oil from oilseed rape.
A much longer list of possible current and future biomass energy technology chains in a European context has been identified within the BIOMITRE project, which runs to around 900 potential technology combinations. Clearly, extending this to other geographical regions means there are likely to be well over 1,000 possible such combinations worldwide. This has clear implications for the potential accuracy and flexibility of the BIOMITRE Tool. 3.4 Net Emissions Calculations of indirect greenhouse gas emissions are based on emission factors, which indicate the fossil emissions produced per unit of energy available when a fuel is burnt or electricity is generated. For example, the term gross carbon coefficient can be adopted to represent the total CO2 emissions produced per unit of energy available from fuels or electricity (also measured as kg CO2/MJ). Using appropriate coefficients for all greenhouse gas emissions, it is possible to derive the greenhouse gas requirement of a product or service, which consists of the total emissions due to primary fossil energy use in providing a unit of the product or service under consideration, for example, a tonne of bioethanol. Note that primary energy is that available in resources in their natural state, such as coal, natural gas and oil deposits in the ground. As such, it is greater than delivered energy, and generally much greater than the energy services required by consumers, referred to as useful energy. As well as indirect (upstream) and direct emissions arising at the point of use of the product or service, there are those arising from feedstocks - natural resources used in the manufacturing process, which result in the greenhouse gas ultimately being emitted, burnt or decomposing naturally. For example, natural gas is used in commercial inorganic nitrogen fertiliser production, and this is eventually emitted, and so must be included as a feedstock emission of 4 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
fertiliser production, as part of biomass energy production (for crops which use these fertiliser products in the growing process). Hence, the greenhouse gas requirement of a given biomass energy technology is the sum of the climate change effect due to greenhouse gases (such as carbon dioxide, methane and nitrous oxide) arising from the use of fossil fuels and fossil feedstocks. The net greenhouse gas emissions are the sum of the said emissions arising from the biomass energy technology, less those equivalent emissions from the technology chain providing the current typical fossil fuel alternative. 3.5 Allocation Options According to the relevant guidance on allocation methods in ISO14040, there is no single allocation procedure which is appropriate for all circumstances. Market prices can be used to allocate costs between main products, co-products (which receive equal revenues to the main product), by-products (which result in smaller revenues), and waste products (which provide little or no revenue). However, where relative price fluctuations are likely, the results of the GHG analysis will change, and so, some situations lend themselves better to basing allocation procedures on relatively fixed physical rather than varying economic relationships between multiple products. The mass, volume or calorific value of products can be used, although such simple bases for allocation need to be justified satisfactorily. In cases where all the products are fuels, such as petroleum products produced by an oil refinery, allocation by relative output and calorific value can be regarded as appropriate. However, allocation by this means for products which might have calorific values but are not, in fact, used as fuels, is quite tenuous and not really suitable. The preferred allocation procedure uses a substitution approach, where the main process for producing a co-product, by-product or waste product is used to generate comparative effective credits, which are then subtracted from the life cycle inventory of the process chain under investigation. This allocation procedure is fundamentally sound, but clearly increases the scope of the GHG analysis to include process chains of main methods of production of the relevant byproducts and co-products. Effectively, the system boundary is expanded to include both the main product and co- and by-products, and the process chains of the substitutes for these co- and by-products. Also, there is the question of how to substitute when a co-product, by-product or waste product in question is not normally produced by any main process. Because allocation is a complex, time-consuming process, sometimes of questionable accuracy, some studies have chosen to ignore it altogether. This effectively provides an allocation of 100% to the biomass energy product, and is manifestly inaccurate and should therefore be avoided. The best way to deal with uncertainty in allocation is to maximise transparency and, if possible, show what the effect of a range of allocation values might be on the results. 4.
EXISTING BIOMASS ENERGY STUDIES
As discussed above, there are a vast range of potential biomass energy production chains. Some have had many studies of greenhouse gas emissions implications performed upon them, while others have had none. The recent biofuels study which identified the 18 technology options listed above, also reviewed 43 existing studies potentially relevant to the UK. A more recent study [9] reviewed some 500 studies and identified 51 major existing studies in a European context. These studies have been performed in various ways to achieve diverse objectives, and are presented in different degrees of transparency. The studies were essentially designed for different purposes, therefore, the review and critique was not designed to find out whether there were shortcomings in work in the context in which it was undertaken, but the extent to which that work may be utilised in the BIOMITRE project. The review criteria included coverage (in terms of estimates of energy inputs, CO2 emissions, other specified GHG emissions and aggregated GHG emissions), transparency (in relation to methods and details of calculation) and relevance (as regards the countries where the results are applicable). While space precludes comprehensive documentation of the process and content of this review, the results are clearly of significance in informing the development and requirements of a new decision support tool for undertaking GHG and cost-effectiveness calculations, which is the main aim of this paper. Hence, a summary of the results of this review is important here. The review established that many existing studies are partial or opaque, although based at least partially on LCA methodology. There is a wide range of relative transparency and treatment and use of disaggregated and aggregated data. Equally, the full range of possible techniques are used in allocation, as well as, in some studies, no allocation at all. Indeed, the main outcome of the critique of existing studies is the dual observation that transparency is essential but often lacking, and approaches to allocation are often partial, implicit, arbitrary and, hence, confusing and misleading. In particular, practitioners often mix procedures (and terms) to address allocation in different studies and different parts of the process chain. For example, the following terms are used variously to describe varied approaches to allocation by substitution; "expanding the systems boundaries", "specifying reference systems" and "using substitution credits". 5 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
For example, in one biodiesel study [10], relatively transparent, complete details are provided for the derivation of primary energy inputs, however, only partial details are provided for the calculation of CO2 emissions, and no other greenhouse gas emissions are considered. The allocation procedure adopted for the main results is based on the calorific values of all co-products (rape straw, rape meal and glycerine), although none of these are used as a fuel currently. Another study [11] is a comparative assessment of emissions of road transport fuels, which includes a high level of transparency and evaluation of the effects of allocation procedures. However, allocation by price, consistent with the associated economic assessment, is not considered. In general, this work updates that of the earlier ETSU (now Future Energy Solutions) report [10]. Hence, it may be affected by some of the data weaknesses of the earlier work. A further study [12] includes a range of different allocation procedures (calorific value, mass and price) are considered, and their effects on results are demonstrated. However, the main results are based on a mixture of allocation procedures (mass for raw rapeseed and rape straw, price for rapeseed oil and rape meal, and biodiesel and glycerine), and not all are logically consistent. Kaltschmitt & Reinhardt [1] include detailed LCA calculations of several biofuels (wood residues, short rotation coppice, perennial grasses, cereals, bioethanol from several sources, rapeseed oil and rape methyl ester). Greenhouse gas emissions have been calculated in a consistent and relatively transparent manner. In addition, comparisons and sensitivity analysis are included, and a vast range of citations and references are used. Allocation is achieved using various methods, although the main option chosen is based on price. One of the most transparent biofuels studies [2] establishes a standard method for describing the process chain and reporting calculation procedures and reference sources. Allocation of relevant primary energy inputs and greenhouse gas emissions outputs is based on market prices. The explanation for this is included, namely, that "Typically, substitution is preferred ... However, many of the co-products of biofuel technologies have no separate main means of production ... In the absence of a physical basis for partitioning, it becomes necessary to use an allocation procedure based on the relative economic value of main and co-products". In summary, then, the review process revealed that there are various ‘problems’ with existing studies, not internally, but in terms of their potential use in development of the BIOMITTRE Tool, and in the extent to which clarity, transparency, and a standardised approach are achieved currently. Such problems mean that many of these studies do not provide directly comparable results, since the approaches taken to greenhouse gas and cost-effectiveness calculations varies, as does the standard of data upon which these calculations are based. 5.
SOFTWARE DESIGN REQUIREMENTS
Several tools are available which could be used to calculate and evaluate GHG-balances and cost-effectiveness of biomass energy technologies [13]. The disadvantage of these tools is that they are either of non-specific LCA design, or they are complicated to use, or they are restricted to one biomass energy technology or resource (e.g. CO2Fix is limited to forestry). This makes it difficult to compare data of GHG-balances and cost-effectiveness of biomass energy technologies. As a result of the review of current studies, their methodological strengths and weaknesses can be identified in relation to the objectives for the BIOMITRE Tool, i.e. evaluating greenhouse gas balances and emissions-saving costeffectiveness of prominent biomass energy technologies relevant to the European Union. Three categories of key questions were recognized and applied to each method evaluated [9]: •
Accuracy of the methodology; considering comprehensiveness (functional unit, system boundaries in time and space, reference system etc.) and consistency (consistent treatment of actual and reference system, etc.)
•
Transparency (assumptions clearly shown, use of flow charts and sensitivity analyses)
•
Efficiency (appropriate level of detail balanced with ease-of-use, comparable output parameters)
These criteria follow from the aim of the BIOMITRE project to develop a standard, user-friendly software tool that provides for transparency and standardisation of approach, and therefore, reliable and comparable results. The tool has to be able to accommodate a diversity of biomass technologies. It has to be applicable for different user groups such as universities, policy-makers or companies involved in biomass technologies. By virtue of its intended application, it is important that the BIOMITRE Tool provides a transparent, essentially modular design which reflects the specific elements of biomass energy technologies and their diversity. Established case studies must supply basic data within the software tool which incorporate unified and documented methodologies. This enables the software tool to be tested and used to generate further case study material. It must also be flexible enough to allow LCA practitioners to input their own data for a particular technology, area, time, and/or specific project, in order to assist in GHG and cost effectiveness evaluation. 6 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
The Tool must be generally-applicable to all major commercial biomass energy technologies, including agricultural and forestry residues, energy crops and wastes. Additionally, it should encompass all the important elements of these technologies, including production (cultivation, harvesting, recovery. etc.), processing (chipping, pelletisation, baling, etc.), transportation (by road, rail, waterways, etc.), conversion (direct combustion, co-firing, gasification, pyrolysis, digestion, etc.) and end-product utilisation (heat, power, combined heat and power, liquid biofuels, etc.). 6.
THE BIOMITRE TOOL AND ITS USE
The design requirements discussed above were incorporated into the BIOMITRE Tool. The result is a Tool which uses a standardised method. This is good for consistency of results, although clearly it places some constraints on the flexibility of the method and use of the Tool. However, since one of the main purposes of the BIOMITRE project is to unify methodologies into a standard approach for evaluating the greenhouse gas (GHG) balances and cost-effectiveness of GHG savings associated with biomass technologies, this compromise is inherent within the project from inception. 6.1 Standard Methodology A main finding of the review of methodologies was that accuracy is the foremost methodological aspect to consider. Comprehensiveness and consistency are key factors of an accurate methodological approach. System boundaries, in time and space, should be set to include all differences in GHG emission and cost between the bio-energy and the reference system. For example, the functional unit should include end-use efficiency, if it varies between compared systems [9]. The methodology used to describe the compared (reference) systems, is also consistent and the same technical level is used in comparisons. All assumptions and calculations can be derived easily, and, from an efficiency point of view, details with a small impact on the results in relation to uncertainties of other parameters might be omitted, so time can be given to reducing the uncertainties of the other parameters instead. The tool is developed in the software program Excel, and is accompanied with Technical and User Manuals [14, 15] that serve as background material and guide for the user. It incorporates case studies that demonstrate examples of the wide diversity of biomass technologies and resources that can be accommodated by the tool (Table 1), and is based on standard
Case study
Resource
Use
Reference system
1
Rapeseed
RME plant
Diesel
2
Forest residues
F-Tropsch
Diesel, grid (electricity)
3
Wood
CHP plant
Electricity North Europe
4
Miscanthus
Domestic heat
Oil fired heat
7 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
Table 1: Set of established case studies incorporated into the BIOMITRE tool Reference system
Production biomass Ton / ha * year Yield performance over time
Biomass system 1. Biomass source 2. A. ---3. A. ---- B. ---A. ---- B. ---2 A B. ----
1. Supply system 2. A. ---3. A. ---- B. ---A. ---- B. ---2 A B. ----
1. Original land use 2. A. ---3. A. ---- B. ---A. ---- B. ---2 A B. ----
Carbon stocks (changes)
Transfer
Performance over time
Original use
Amount of carbon in soil
Harvest
Role of leakage
Reference use and 2. supply system 3. A. ---- A. ---A. ---- B. ---2 A B. ----
i.e. landfill municipal waste
Storage
Pre-treatment Energy system (time dependent)
1. Conversion 2. A. ---3. A. ---- B. ---A. ---- B. ---B. ----
1. End-Use 2. A. ---3. A. ---- B. ---A. ---- B. ---B. ----
Energy system (time dependent)
1. Conversion 2. A. ---3. A. ---- B. ---A. ---- B. ---B. ----
Carbon intensity may go down. Efficiency system. Cost dynamics over time
2 A Material system (quality, lifetime material)
2 A Material system (quality, lifetime material)
2 A
Efficiency (type of end-user)
1. End-Use 2. A. ---3. A. ---- B. ---A. ---- B. ---B. ----
2 A
Result GHG balance and cost-effectiveness
Figure 2: Flow chart design for software tool BIOMITRE
8 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
A main component of the tool is the resource module. The tool identifies as resources perennial crops, annual crops, forest and waste. In terms of supply, the main initial input resources (seed, cuttings, land, etc.) are indicated. Coproducts and by-products that occur at any stage in the biomass technology are taken into account since these can have a significant role in final evaluation through allocation procedures. The modular approach is in accordance with a model developed elsewhere [16], and is also used for the logistics (train, ship, truck transport) to supply biomass to the conversion unit. The end-use possibilities are forms of delivered energy (solid, liquid and gaseous fuels, heat, electricity, heat, etc.). 6.2 Data Of course, the tool cannot provide all data for the wide range of users because they are project specific and unique in location and site. In general, there are three different possibilities for data input for the user: •
The data are already covered in the set of case studies
•
The knowledge of the process system is available and the modules are included in the tool. The user has to collect its own data in international databases.
•
There is a lack of data, also in international databases (new technologies). The framework of the required module and data input for the process is presented in the tool. However, the user might have to do some adaptations in input and output data.
The variation in data availability has its impact on the levels of calculation within the software tool. Therefore, successive disaggregating is used to be able to cope with this data diversity. The key concept of the software tool design is that different “tiers” for greenhouse gas (and cost) calculations and, thus, data requirements are used. This enables users to adopt either aggregated or disaggregated data for subsequent analysis. Hence, three different tiers within the tool provide the user the possibility to choose its own attainable degree of data specificness (Fig. 3). Of course, the output is related to the data input. This means that calculations in tier three generate a more exact data output than calculations in tier one.
Resource GHG & costs
Level 0
Supply GHG & costs
Allocation
Level 1
Level 2
Perennial crops
Annual crops Costs / GHG
Waste and residues
Short rotation coppice
Operations
Machines GHG / ha*yr costs
Carbon pools GHG / ha*yr costs
Inputs GHG / ha*yr costs
GHG / ha*yr costs
Set of Inputs:
Level 3
Set of operations:
Phosphate
Soil preparation
Potash
Sowing / drilling
Lime
Crop husbandry
CaO fertiliser
Collecting crop
Pesticides generic
Other operations
Soil preparations Sub-soiling Ploughing Harrowing
Herbicides generic Seedlings Other
Figure 3: The tool provides the user different levels of calculation and thus data requirement. In this example the module “biomass resources: shows three different levels of calculation.
7.
CONCLUSIONS AND FURTHER WORK
The first conclusion which can be drawn is that the reporting procedure is as important as the allocation method used. Transparency is critical; it should be clear how, where and why allocation has taken place. Provided a logical process 9 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
is followed, such as the decision tree approach, various allocation methods are possible. Combining these with a modular, transparent systems approach, based on process chain analysis, with critical and open referencing, is important in validating allocation methods used in all biomass energy assessment work. This also means that parts of each scenario can be updated as data and/or technology develops, thus rendering the studies updateable rather than short-dated. Apart from minor improvements in frame-level utility, the main potential areas for further development of the BIOMITRE Tool are: •
Incorporation of more data/case studies in order that users without data can use the Tool for a wider range of applications,
•
Expansion of the geographical application of the Tool.
Indeed, it is likely that these two areas are interlinked, since it is expected that the basic infrastructure of the Tool is already 'internationalised', so the main work involved in the latter would be to incorporate non-European datasets and cases. 8.
REFERENCES
1.
Kaltschmitt, M. and G. A. Reinhardt (eds). 1997. Nachwachsende Energieträger – Grundlagen, Verfaben, Ökologische Bilanzierung. (Renewable Energy Sources, Basis, Processes and Ecological Balance). Vieweg, Braunschweig/Weisbaden, Germany.
2.
Elsayed, M. A, Matthews, R and Mortimer, N. D. 2003. Carbon and Energy Balances for a Range of Biofuels Options. Commissioned by the Energy Technology Support Unit, under Contract No. B/B6/000784/00/00.
3.
Wahlund, B, Yan, J and Westermark, M. 2004. Increasing biomass utilisation in energy systems: A comparative study of CO2 reduction and cost for different bioenergy processing options. Biomass and Bioenergy, 26, 6, June, pp. 531-544.
4.
ECS. 1997. Environmental Management – Life Cycle Assessment – Principles and Framework. European Standard ISO 14040, European Committee for Standardisation, Brussels, Belgium.
5.
ECS. 1998. Environmental Management - Life Cycle Assessment - Goal and Scope Definition and Inventory Analysis. European Standard EN ISO 14041, European Committee for Standardisation, Brussels, Belgium, October.
6.
ECS. 1999. Environmental Management – Life Cycle Assessment – Goal and Scope Definition and Inventory Analysis. European Standard ISO 14041, European Committee for Standardisation, Brussels, Belgium.
7.
ECS. 2000. Environmental Management – Life Cycle Assessment – Life Cycle Impact Assessment. European Standard ISO 14042, European Committee for Standardisation, Brussels, Belgium.
8.
ECS. 2000. Environmental Management – Life Cycle Assessment – Life Cycle Interpretation. European Standard ISO 14043, European Committee for Standardisation, Brussels, Belgium.
9.
Vikman, P-A, Gustavsson, L and Klang, A. 2004. Evaluating Greenhouse Gas Balances and Mitigation Costs of Bioenergy Systems – A Review of Methodologies. Final draft, June. Mid-Sweden University.
10.
Culshaw, F. and Butler, C. 1992. A Review of the Potential of Biodiesel as a Transport Fuel. ETSU-R-71, Energy Technology Support Unit, Harwell, United Kingdom, September.
11.
Gover, M. P., Collings, S. A., Hitchcock, G. S., Moon, D. P. and Williams, G. T. 1996. Alternative Road Transport Fuels – A Preliminary Life-Cycle Study for the UK. Report R92, Volume 2, Energy Technology Support Unit, Harwell, United Kingdom, March.
12.
Spirinckx, C., and Ceuterick, D. 1996. Comparative Life-Cycle Assessment of Diesel and Biodiesel. Flemish Institute for Technological Research, Mol, Belgium.
13.
http://www.joanneum.ac.at/iea-bioenergy-task38/softwaretools/
14.
Horne, R E and Matthews, R. 2004. BIOMITRE Technical Manual. For use with the BIOMITRE Software Tool. November. www.joanneum.at/biomitre
15.
Van dam, J. Faaij, A. and Lewandowski, I. 2004. BIOMITRE User Manual. Developed by the Copernicus Institute, October. www.joanneum.at/biomitre 10
Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
16.
Hamelinck, C N, Suurs, R and Faaij, A. 2003. International bioenergy transport costs and energy balance. Copernicus Institute Utrecht University
11 Paper presented at the 4th Australian LCA Conference, February 2005, Sydney
