AIR3-CT94-2455 Environmental Aspects of Biomass Production and Routes for European Energy Supply

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	Proposal No:	AIR3-CT94-2455
	Date Prepared:	September 1999
	Source:	Final report March 1997

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Final report March 1997

Summary

Introduction The Concerted Action was set up to reinforce communication between researchers working on environmental aspects of biomass for energy. Over twenty organisations from 12 different European countries participated to exchange insights and experiences relating to the analysis of environmental impact of relevant biomass routes in Europe. The main focus was on the environmental impact of the production of biomass, rather than on the environmental impact of conversion. The concerted action have been included an international workshop of participants and an international conference that was open to other organisations as well.

Objectives The aims of the Concerted Action were:

• to improve knowledge and insights of the participating partners
• to identify differences in national insights and causes of these differences
• to reach consensus where possible about guidelines for environmental analysis, about major environmental issues and about possible solutions for environmental problems

To reach these objectives the Concerted Action has focused on:

• analysis and assessment of the environmental impact of the relevant biomass routes for energy supply in Europe
• assessment of feasible ways to reduce negative environmental effects and to increase positive environmental effects
• assessment to what extent biomass can play a role in European energy supply with respect to environmental impact, agricultural development and land use

Conclusions

On the basis of the results of the conference some major conclusions have been reached and published in conference proceedings, edited by the co-ordinator. These are summarised below.

Evaluation methods It is necessary to analyse all relevant environmental aspects of the production and use of biomass for energy in a univocal and consistent methodology. A chain analysis, analysing the environmental impact during the whole process chain ('from cradle to grave'), is necessary for many of the different environmental aspects. For most purposes, the methodology of environmental Life Cycle Assessment (LCA) is the suitable instrument available. LCA focuses on global, not site-specific aspects. LCA can be used: - to compare the environmental impacts of other products used for the same goal e.g. biomass with other energy carriers or different biomass options; and - to optimise specific production processes.

There still is a need for further development and standardisation of LCA. At the moment little experience has been gained with use of LCA for the assessment of the environmental impacts of biomass for energy. In particular, the agricultural phase of the biomass chain needs further work. Additional criteria and methods for LCA should be developed. Although LCA deals with a large number of environmental themes, several themes still have to be added, such as erosion, water use (groundwater depletion or man-induced drought), biodiversity and landscape. There are some criteria for biodiversity that can be used, such as 'species diversity' and 'threatened species'; however, a generally accepted and widely used methodology to evaluate the impact of biomass development on biodiversity does not yet exist.

Crucial elements in LCA and other chain analyses are set out below.

Clear and explicit functional units The functional unit describes the central function of the product under scrutiny and defines how this function is quantified. Choosing a proper functional unit is very important and functional units should be described clearly. The choice of functional unit largely depends on the goal of the LCA.

Explicit assumptions, data and sources There will always be a lack of reliable and empirically sound input data. This means that assumptions cannot be avoided. However, assumptions should be based as much as possible on a combination of theoretical and empirical insights and data. The basis of the assumptions should be made explicit.

Comparison with the reference system A proper comparison between different alternatives requires a clear definition and description of both the biomass system and the reference system. Cornerstones of this are functional unit and system boundaries. The state of technology in both systems should be comparable. For example: when biomass is compared with coal as an energy carrier and an increase in efficiency level is assumed for biomass, then potential new technologies for coal should be used as the reference system. Set-aside is the preferred reference system for land use.

By-products When relevant by-products are produced, environmental impacts should not be allocated to the main product only. In these cases, substitution is preferred to division; impacts are divided between the main and by-products based on mass, economic value or energy value. Using substitution, the energy needed to produce a product substituted by the by-product is added to the energy output of the main product. After substitution, all environmental impacts can be allocated to the main product.

Valuation and interpretation It is essential to present a discussion of both the advantages and disadvantages of alternative energy carriers as well as a final judgement.

Several methods for the final evaluation have been proposed. Whenever possible priority should be given to:

• unweighted results
• qualitative weighting
• quantitative weighting

After the evaluation an interpretation should be given, showing how the results can be used for different purposes, and indicating what cannot be done with the results. Environmental Impact Analysis (EIA) is a good instrument for exploring the possible environmental impacts of proposals for local biomass projects. Within a specific EIA, LCA can be used to quantify certain environmental impacts.

State-of-the-art on the environmental impacts of biomass From the presentation of the state-of-the-art knowledge on environmental impacts of biomass for energy it was concluded that a considerable amount of work has been done in recent years. The level of knowledge and understanding are improving rapidly and initial conclusions can be drawn. One important source of knowledge on the environmental impacts of biomass for energy is a LCA carried out by German researchers (Kaltschmitt & Reinhardt 1996). The conclusions of this research are:

• the impact of the use of biomass for energy is positive for energy balance and global warming
• the impact is negative, or slightly positive, for ozone depletion, acidification and human toxicity

In the Netherlands research has been carried out by the Centre for Agriculture and Environment (CLM) (Biewinga & van der Bijl 1996) using a method that is closely related to LCA. The conclusions from this report are:

• for energy and global warming the impact of biomass for energy is positive
• for electricity routes the scores for other environmental aspects are neutral or limited, with the exception of a negative score for erosion
• for liquid fuel routes scores are negative for ozone, minerals, pesticides and erosion

The general conclusion emerging from the available studies is that energy from biomass is generally preferable to fossil fuels from an environmental point of view. However, it should be stressed that environmental impact varies considerably from one source of biomass to another. Moreover, it is not always certain that biomass is the best alternative. In some cases alternatives other than the energy carrier in the reference system (e.g. other renewable energy sources) may be better. Although it has been concluded that the impact of biomass on biodiversity is difficult to establish - and especially to quantify - it is assumed and agreed that the impact of short-rotation forestry on biodiversity is on a level with common agricultural practices, on the one hand, and nature reserves or unclaimed land on the other.

It should be recognised that in spite of the progress there still is a considerable lack of knowledge in specific areas. This lack of knowledge is due partly to an absence of well-defined methodologies and partly to a lack of data. Examples of expertise deficiencies include:

• carbon in soil - although it may not be a large impact, the possible effect of biomass on carbon accumulation in soil has not yet been properly assessed
• measuring nitrogen surpluses - the effect of denitrification losses (including the emission of nitrous oxide) is often not taken into account
• the impact of biomass for energy on biodiversity is difficult to evaluate, both because of a lack of data and the absence of a generally accepted method
• the impact of biomass for energy on the landscape is difficult to assess, because the evaluation very much depends upon perceptions of the landscape, which tend to vary across the European Union

Opportunities for improving the use of biomass for energy A considerable number of measures to increase the positive impacts or reduce the negative impacts of the use of biomass for energy were recognised. Measures to improve the use of biomass for energy can involve three aspects:

• choice of crops and conversion routes
• choice of location
• management improvements

The benefits of the use of biomass for energy can also be increased by integrating aims, especially site-specific aims. Examples are:

• the use of set-aside land for energy cropping, which can be combined with a reduction of surpluses of agricultural products
• specific management to enhance biodiversity and/or to promote an attractive landscape
• regional differences in perceptions of the landscape may present opportunities for energy crops
• erosion prevention
• specific management to reduce the risk of forest or shrub fires
• uptake of heavy metals; experience, especially in Sweden, shows that energy cropping can also be used to extract heavy metals from polluted soils
• by-products, such as glycerine from oilseed rape

The optimum crop and/or conversion route depends on different factors. Several site-specific circumstances (such as climate, soil or social aspects) are among these factors. Also site- specific aims will influence the optimum crop and/or conversion routes. For example, among the crops for electricity routes, short-rotation crops are preferred if the enhancement of biodiversity is considered an important aim, and annual crops are to be preferred if energy crops are stimulated on land that is set aside for a short period. This means that detailed univocal conclusions on crops and conversion routes cannot be drawn. However, from the available research and practice it can be concluded that in general energy crops used for electricity routes are to be preferred, from an environmental point of view, above energy crops used for liquid fuels. Integrated or sustainable management of crops should be promoted. For example:

• fertilisation should be limited to the real needs of plants, including mineralisation
• organic manure should be used where possible
• erosion control should be achieved by narrow planting or by avoiding bare soil in winter
• biodiversity could be enhanced by using guidelines such as those developed in the UK

The results of LCAs should be used to identify weak points in the production process from an environmental point of view and to combat these weak points.

The role biomass can play in European energy strategy The various studies available on the role biomass can play in European energy supply give different figures for the amount of land that may become available for energy cropping in the future. These differences are caused by differences in both methodology and assumptions. The amount of land that may be available for energy cropping depends both on the decrease in area needed for 'traditional' agricultural production and on other claims on the available land. Two important economic factors determine the role biomass can play in European energy supply:

• the profitability of biomass compared with other land claims - land availability is no longer a problem if energy cropping becomes more profitable for farmers than other crops
• the cost price of biomass energy compared with other renewable energy sources.

Each evaluation of land availability should analyse these aspects. Preliminary estimates show that the amount of land potentially available in the European Union will be around 40 million hectares. Some studies claim that this amount of land will be available by 2010. More pessimistic researchers expect that this amount will be available in 2040. For the use of this land, energy cropping will have to compete with other possible (and sometimes potentially sustainable) land uses.

Therefore, it seems reasonable to expect that the amount of land available for energy cropping will be in the range of 5 to 30 million hectares in 2025. A lot of effort will be needed in order to realise this potential. This will depend upon:

• EU and national policies to promote renewable energies / biomass energy
• the Common Agricultural Policy which determines the amount of set-aside and attractiveness of the various possibilities for agricultural land use
• the linkage between national policies on biomass for energy, and regional initiatives to promote biomass production and use
• site-specific integration: the success of endeavours to make use of synergies and promote multi-purpose biomass for energy
• the development and dissemination of techniques for the sustainable management of the production and use of biomass for energy
• co-operation between the various interest groups such as energy producers, farmers, environmental organisations and nature conservationists
• various other factors (technical, economical and political) which determine the relative attractiveness of alternative land uses and energy sources

Recommendations

Several suggestions for research on the environmental impact of biomass for energy have emerged from the conference. Five main suggestions are listed below.

International projects to test and further improve the methodology of LCA on biomass for energy. The methodology of LCA is considered to be promising. However, it is recognised that further research and development activities in the field of LCA are necessary.

Studies on the further development of a methodology to evaluate environmental criteria, such as biodiversity, are needed. The need for a good methodology to evaluate the impact of biomass for energy on specific environmental themes is generally recognised. For some environmental themes, such as the emission of greenhouse gases or the use of energy resources, generally accepted and suitable methodologies with univocal indicators are available. For other environmental themes, however, this is not the case. An example is biodiversity. The need for a proper evaluation of the impacts of biomass for energy on biodiversity is widely recognised but, at the moment, generally accepted and workable methodologies to evaluate the impact of biomass for energy on biodiversity do not exist.

A vast amount of research has been executed on the optimisation of different elements in the chain of production and the use of biomass for energy. Feasible techniques are becoming available, increasing the need for international co-ordination of research on case studies concerning regional options. Comparison of case studies from different regions in the European Union can form the basis for recommendations for optimisation per case, regarding site selection, choice of crop and routes, and management. Both Environmental Impact Assessment and Life Cycle Assessment can play a role in finding optimal solutions.

The growing availability of feasible techniques creates an increasing need for regional pilot projects to investigate improvements in management, combined with research on environmental consequences of the different techniques.

Finally, there is a growing need for research on the effects and potentials of different policy measures to stimulate the use of biomass for energy and other renewable energy sources.