DECEMBER 1997 ECN-I--97-050

COMPARATIVE ENVIRONMENTAL LIFE CYCLEASSESSMENT OF COMPOSITE MATERIALS

O.M. DE VEGTW.G. HAIJE

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CONTENTS

CONTENTS 3

1. INTRODUCTION 5

2. GOAL AND SCOPE DEFINITION 7

3. LIFE CYCLE INVENTORY 93.1 Flaxfibre reinforced epoxy rotorblades 93.2 Carbon fibre reinforced epoxy rotorblades 123.3 Glassfibre reinforced polyester rotorblades 14

4. IMPACT ASSESSMENT 154.1 Classification 154.2 Normalisation 164.3 Evaluation 17

5. ENVIRONMENTALLY SOUND MATERIAL SELECTION 19

6. DISCUSSION 23

7. CONCLUSIONS 25

8. RECOMMENDATIONS 27

REFERENCES 29

APPENDIX A ECO INDICATOR 31

APPENDIX B IMPACT TABLE 33

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1. INTRODUCTION

The environmental soundness of materials is a very complicated issue. The aim of the presentstudy is to compare and quantify the environmental impact of three rotorblades made ofdifferent materials and to establish which stage in the life cycle contributes most. The life cycleof a product can be represented by the following stages:

• the production phase;• the utilisation phase;• the disposal phase.

The production phase includes depletion of raw materials (mining) and production (machining)of products. The utilisation phase includes use of energy, maintenance and cleaning. Thedisposal phase finally includes landfill, incineration, recycling etc. The environmental impact ofa product is not only determined by the materials selected but also by the function of the productitself. For instance when natural fibres are applied in vehicles as a substitution for metals theenvironmental impact in the use phase will be reduced due to a lower energy consumptioncaused by a lower car weight. The influence on the environmental impact of the productionphase has also to be taken into account. The material relation between the production phase andthe use phase and the disposal phase is complicated. In general the lifetime of a product usephase can be extended (positive aspect) for instance by application of a coating onto the surface.Due to the coating the product can not easily be recycled, which is a negative aspect. Thiscomplex interaction between a product and the environment is dealt with in a Life CycleAssessment (LCA) [Heijungs et al., 1992].

The three types of composites used in the rotorblade of the wind energy converter considered inthis study are: flaxfibre reinforced epoxy, carbon fibre reinforced epoxy and glassfibrereinforced polyester. The assessment is performed using the computer program Simapro 3[Goedkoop, 1995], which is based on the Dutch CML [Heijungs et al., 1992] method for theenvironmental life-cycle assessment of products using the Eco-Indicator 95 evaluation method.The CML method defines five phases for an LCA:

• goal definition and scoping;• inventory;• classification;• impact assessment;• improvement analysis.

The improvement analysis is not part of this work. In the scope of the project “environmentallysound material selection”1 another comparative LCA concerning different coatings on asteelplate has been carried out and has been published in report ECN-I-97-001 [Haperen andHaije 1997]. Performing an LCA is a time-consuming process due to the detailed informationwhich is required. In chapter five we formulate some general guidelines for incorporatingenvironment related issues into the design process, especially relating to composite materials,without performing an exhaustive LCA.

This study ends with our main conclusions and recommendations.

1 milieubewuste materiaalkeuze

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2. GOAL AND SCOPE DEFINITION

Goal of this investigation is a comparison between the environmental impact of three types ofcomposites applied in a windrotorblade used in a three bladed wind energy converter. Theassembly of the glassfibre rotorblade to the rotor is different from the carbon- and flaxfibrerotorblade. The glassfibre reinforced rotorblade is assembled with a flange to the rotor incontrast with the carbon- and the flaxfibre reinforced rotorblades. The carbon- and flax fibrerotorblades contains fixing holes at the root in which the rotor tube precisely fits. Therefore theamount of steel used in the blade is a crucial parameter.

The functional unit for this LCA is defined as follows:a windrotorblade to be applied in a 250 kW wind energy converter with a usetime ofx years.

In which x is the same for each rotorblade but not relevant for this LCA-study. Furthermore, theenergy production of a wind energy converter is not taken into account.

Due to the aspect that not all aspects can be taken into account in a detailed way or withsufficient accuracy the LCA performed is a streamlining one.

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3. LIFE CYCLE INVENTORY

In the inventory phase all relevant environmental interventions relating to the different phases ofthe rotorblade life cycle are collected and quantified. The life cycle of rotorblades consistsroughly of four phases: extraction and processing of raw materials, product manufacture, use ofthe product and waste scenario of the product. The main life cycle steps of the rotorblades arerepresented in figure3.1. In this LCA three types of rotor blades are considered: flaxfibrereinforced epoxy rotorblades, carbon fibre reinforced epoxy rotorblades and glassfibrereinforced polyester rotorblades. The production of flaxfibre and carbon fibre rotorblades aredescribed in the following sections. The glassfibre rotorblade is described in detail elsewhere [Kok, 1996 ].

Figure 3.1 Processing steps of a windrotorblade

3.1 Flaxfibre reinforced epoxy rotorblades

At the moment most rotorblades are manufactured from polyester- or epoxy resins reinforcedwith glass- or carbon fibres. Flaxfibres have not been applied in the manufacturing ofrotorblades as yet. Therefore to perform an LCA of flaxfibres applied in rotorblades, we basedour data upon the quantity of carbon fibre applied in a 250 kW rotorblade. From the welldocumented data the amount of flaxfibre has been calculated based on the densities of carbonfibre and flaxfibre.

The inventory of flaxfibre reinforced epoxy rotorblades starts with with the production of rawmaterial required for the manufacturing of rotorblades and ends with the disposal of rotorblades.More specifically the following life cycle phases are considered: agricultural cultivation andtreatment of flax, production of the epoxy resin, rotor mould manufacturing, the use- anddisposal phases.

disposal phase

use phase

rotorblade manufacture

raw materials

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fax cultivation epichlorohydrin bisphenol-A

flaxfibre treatmentepoxy resin prod.

mould manuf.

rotorblade manufacture

use phase

disposal

Figure 3.2 Process scheme of flaxfibre reinforced rotorblade

The cultivation of flax consists of several phases. The land needs to bo plowed, before thatseeds are sown. The crop has to be protected against different pests, and the crop needs nutrientsin the form of fertilizers. The cultivation needs about 5 kg pesticides /hectare a year. Thiscorresponds with an amount of active compound of 1.3 kg/hectare a year. It is assumed that12.9% of this active compound are waterborn emissions and 23% are airborne emissions [IMSA, 1994].Finally the crop can be harvested. The yield of flax is 1.65 ton/ha [3]. For each of these phases atractor is necessary. Emissions descended from the tractor are derived from Idemat[Remmerswaal, 1996]. The emissions are given in the appendix.

With regard to CO2 emissions the assimilation of CO2 during the flax growth has been takeninto account. The CO2 fixation per kg flax is given in table 3.1.

Table 3.1 Carbon dioxide fix for the cultivation of flax

Composition of flax fibres: Molweight C-percentage CO2 - fix71% cellulose (C6H10O5) 162 g 44% 71%*3,6*44%=1124,6 g/kg flax19% hemicellulose (C5H10O5) 150 g 40% 19%*3,6*40%=273,6 g/kg flax4% lignine (C10H12O3) 180 g 66% 4%*3,6*66%=95g/kg flaxTOTAL 1493 g/kg flax

The fibres can be obtained from the harvested stems by different isolation processes so that thewood components may be more easily separated from the fibre constituents. In the past thisprocess had been accomplished by dew-retting. Dew-retting means that the flax is left on thefield during 3-4 weeks. It calls for dry weather towards the end of the process if the flax is not tobecome over retted. When flax after harvesting is immediatly taken away from the field this isthe so-called green-flax. The green-flax is sensitive to rot and moisture and hence can not beapplied in rotorblades because of its detrimental properties.

The composition of green flax is about 19 w% hemicellulose, 4 w% lignine and 71 w%cellulose, the remainder are pectines, nitrogen, pectose and ash [Fritz, 1994]. Hemicellulose is

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the most sensitive fraction because of the high water absorption (its own weight) and swell. Thegreen-flax must be treated in order to withstand the influence of moisture. A novel process[CERES] which uses green-flax is considered for this LCA. The treatment of green-flax isgiven below in the proces scheme.

Figure 3.3 Treatment of strawflax

The flax-treatment process does not use dew retted flax as a feedstock but the full rippled(deseeded) stalk, the straw-flax. This proces contains three phases. The first phase is athermolysis. This means that sheaves of straw-flax are treated in water at a temperature of about180°C in a autoclave during 30 minutes. The second step is a drying step at 80°C. Thereafter acuring step takes place at temperatures above 150°C during two hours to thermoset the resincomponents. The energy in the form of heat needed for the flax treatment is calculated to be9.3 MJ/kg. After this process lignine and hemicellulose are converted into an inert resin whichdoes not absorb water. This reduces the rot sensitivity, thereby extending the lifetime of ligno-cellulose fibres.

The flax thus obtained is assumed to be applied in rotorblades. The rotorblade has a length of13,4 m and a global mass of 300 kg. A flaxfibre polymer composite is composed of flaxfibresand a epoxy resin. The structure of the rotor blade consists of two shells and two spars made offlax-epoxy and glass epoxy laminate, stratified together with foam cores. After laying out thegel-coat in the mould, the first layers are laid down and after that the unidirectional layers. Thenthe foam cores are placed in the mould and all the other layers are laid down subsequently. Eachlayer is impregnated separatetely with the epoxy resin on a table and rolled beforehand. Thismethod is called the hand-lay-up method. The surface of the blade will have the followinglayers; gel-coat, glass veil, copper-mesh and a epoxy laminate. Based on information from arotorblade manufacturer [Lagerwey] the amount of fibre of any nature applied in a rotorbladeamounts to 0,055 m3. This corresponds to 78 kg flaxfibre applied into one rotorblade. The epoxyresin is produced by the Ciba-Geigy Corporation California. The energy used in the productionof resins is mainly in the form of heat for chemical reactions and mechanical work for stirring.

green flax

thermolysis

drying

curing

treated flax

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The energy consumed in producing epoxy resin from its starting materials amounts 1.74 MJelectric power and 5.5 kg steam per kg epoxy resin produced.The resin contains an organic peroxide used as catalyst. Due to this catalyst curing of theunsaturated resins takes place. The rotorblade also contains stainless steel and compoundswhich are incorporated in the laminate. These compounds containing epoxy resin and fibreglassin the proportion 1:1. The energy consumed in assembly of a rotorblade is assumed to be500 kWh in the form of mechanical work for the machines. Solid emissions arising fromsanding and polishing are disposed of (landfill).

3.2 Carbon fibre reinforced epoxy rotorblades

Process stages for the carbon fibre reinforced epoxy rotorblade are shown in figure 3.4. Carbonfibres are produced from fibre precursors of which the most important is polyacrylonitrile(PAN). PAN is a polymerisation product of acrylonitrile. Acrylonitrile is produced by the Sohioprocess. For one kg acrylonitrile 0.4 kg ammonia and 1 kg propylene are needed [Biekart et al.,1997]. Carbon fibre production involves heating PAN fibres to about 220°C for oxidation andafter that heating to above 1000°C for carbonization. The energy needed for producing carbonfibre is calculated based on a specific heat of 1.26 kJ/kg.K for PAN, and a temperature rise of1000°C, thence the energy consumption amounting to 1.26 MJ/kg. The overall processes resultin 50-55% of the original PAN precursor mass converted to carbon fibres.[Lee et al. 1991].Therefore the energy in the form of heat required for the carbonization proces is about2.52 MJ/kg. With an efficiency of 45% for generating electricity and including other energyconsumption such as heat loss and fibre treatment, the actual energy needed is 7.56 MJ/kg. Forthe carbon fibre production the average energy composition in Asia is selected, because nospecific data regarding the composition of the Japanese energy mix is available in the Simprodatabase. The average composition of one MJ energy in Asia is 35% coal, 53% oil and 9% gas[Remmerswaal, TUD, Warmer ECN].

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Figure 3.4 Process stages for the carbon fibre reinforced epoxy rotorblade

The rotorblade has a length of 13,4 m and a global mass of 300 kg. A carbon fibre polymercomposite is composed of carbon fibres and a epoxy resin produced by the Ciba-GeigyCorporation California. The manufacturing of the rotorblade is the same as is described by theflaxfibre rotorblade. Based on information from Lagerwey the amount of fibre applied in arotorblade amounts to 0,055 m3. This corresponds to 100 kg carbon fibre applied into onerotorblade. The rotorblade also contains stainless steel and compounds which are incorporatedin the laminate. These compounds contain epoxy resin and fibreglass in the proportion 1:1. Theenergy consumed during assembly of a rotorblade is assumed to be 500 kWh in the form ofmechanical work of the machines. Solid emissions arising from sanding and polishing aredisposed of (landfill).

There are certain issues related to end of life of composites in general and in particular ofrotorblades. Composites recycling methods in the strict sense of the word does not exist at themoment.

A wellknown technique is the ERCOM process (reuse of granulated material) [Overbeek,1996]. Other methods [Haije 1994] are:• pyrolysis ( chemical decomposition by heat)

acrylonitrile prod.

polymerization

spinning

stabilization

carbonization

surface treatment

disposal

use phase

rotorblade manufacure

carbon fibre mould manuf.

bisphenol-Aepichlorohydrin

expoxy resin prod.

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• hydrogenation• combustion (use of heat of combustion)

In this LCA study we assumed that rotorblades are discarded2 at the end of life: landfill.However there is a leaching model which can be used of landfill scenarios[7].

3.3 Glassfibre reinforced polyester rotorbladesThe life cycle assessment of glassfibre reinforced polyester rotorblade is given in detail [Kok1997]. This data has been used for calculating the eco-indicator.

Figure 3.5 Process stages for the glass fibre reinforced polyester rotorblade

2 Based on information of producer

glass fibre prod.

glass fibre

epichlorohydrin

disposal

use phase

rotorblademanufacture

epoxy resin prod.mould manuf.

bisphenol-A

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4. IMPACT ASSESSMENT

4.1 ClassificationIn the classification step, all impacts are sorted into classes according to the effect they have onthe environment. The environmental impacts are aggregated within each class to produce aneffectscore. Classification enables the environmental effects of two or more products to becompared. The environmental profiles of the three rotorblades are compared for different impactcategories and presented in figure 4.1. The environmental profiles are entirely caused by theproduction phase. During the use phase there is no maintenance or any other impact on theenvironment. In the disposal phase the rotorblade is discarded.

Figure 4.1 Characterisation for three types of rotorblades observed

With regard to the greenhouse effect flaxfibre has a better effectscore. This is primarily causedby the fact that flaxfibre assimilates CO2 during its growth. The emissions to the air caused bythe carbon fibre production has a higher impact on the summer- and winter smog andacidification compared with glass- and flax fibre which are produced in Europe in contrast withcarbon fibre which mainly is produced in Japan. This is caused by the higher energyconsumption for carbon fibre production.

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The classification step has provided an environmental profile which consists of a fixed set ofclassification scores on the impact categories taken into account. In this figure the rotorbladewith the highest contribution to a particular effect is indicated with a 100% bar. Interpretation ofthis figure may be difficult because comparison between impact categories is impossible.Therefore a normalisation step is performed, in order to gain a better understanding of therelative size of an effect.

4.2 NormalisationIn the normalisation step the effects are set off against a “normal” effect. Via normalisation, theenvironmental impacts of a product are related to the economic activities in a certain regionthrough a certain period of time. The normalisation values are based on average European data[Goedkoop, 1995], this is part of the Eco-indicator 95 method. By executing this step it ispossible to see the relative contribution of the material production to each already existingeffect.

Figure 4.2 Normalisation for the three types of rotorblades observed

Normalisation reveals which effects are large and which are small with respect to other effectsin relative terms. However, it does not yet say anything about the relative importance of theeffects. A small effect can very well be the most important. A weighing step is thereforenecessary to achieve an overall result.

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4.3 EvaluationThe evaluation step converts the impact profile, which is difficult to interpret, into oneenvironmental score, the Eco-indicator 95 and hence this is called the Eco-indicator 95 method[Goedkoop, 1995]. This is a useful quantified number especially when more alternatives arebeing compared. In the Eco-indicator 95 method the weighing of effects are based on the so-called Distance-to-Target principle. This means that weighing factors are based on the distancebetween the current level and target level. The Eco-indicator 95 method makes use of targetlevels which are as much as possible independent of politics and stem from scientificinformation.

Figure 4.3 Evaluation of the three rotorblades considered

The quantified contribution to each impact category is shown in table 2.

Table 4.1 Evaluation

Process/Assembly greenh. ozone acidif. eutroph. h.metals carcin. w.smog s.smog pesticidCarbon fibre Rotor bl. 0.327 0 0.920 0.121 0.150 0.0586 0.310 0.519 0Flaxfibre Rotor bl. 0.181 0 0.536 0.0771 0.150 0.0586 0.176 0.408 0.268Glassfibre Rotor bl. 0.360 0 0.709 0.0867 0.672 0.203 0.171 0.274 0

Adding up the individual weighed effect scores leads to one indicator. This is performed infigure 4.4.

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Figure 4.4 Eco-indicator for the three rotorblades

The results obtained with the eco-indicator 95 method are shown in table 4.2.

Table 4.2 Eco-indicator points of three different 250 kW rotorblades

Eco-indicatorflaxfibre reinforcedepoxy 250 kWrotorblade

flaxfibre reinforcedepoxy 250 kWrotorblade (withoutpesticides

carbon fibre reinforcedepoxy 250 kWrotorblade

glassfibre reinforcedepoxy 250 kWrotorblade

1.85 Pt 1,58 Pt 2,40 Pt 2,47 Pt

Weighing factors may differ from country to country. Political views may affect the weighingprocess as well due to different opinions concerning the relative importance of local or regionalimpact categories. At the moment there is no general accepted method regarding the use ofweighing factors for pesticides. Pesticides are used with the goal to protect the crop i.e. to killinsects. Therefore one can doubt wheter it is justified to incorporate the negative effects (killinginsects) of pesticides in the outcome of an LCA. This is why we made a distinction betweenflaxfibre rotorblades with and without the use of pesticides in table 4.2.

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5. ENVIRONMENTALLY SOUND MATERIAL SELECTION

The term eco-design refers to the process of systematic incorporation of environmental lifecycle considerations into product design. Eco-designed products should be distinguished from'green products' which are niche market products with improved performance (actual orclaimed) in relation to one or more environmental attributes, but where no systematicincorporation of life cycle environmental factors has taken place. Eco-design should also bedistinguished from 'sustainable product design' in which products are designed to contribute tosocially and economically as well as environmentally sustainable development. Eco-designshould be a fully integrated part of companies product development process.

A fundamental difficulty with life cycle assessment is that most companies cannot afford thetime and cost of full LCA exercises. Abridged approaches have been developed to address thisproblem, but there is still a lack of simple design tools, although developments are taking place.The aim of the project “environmentally sound material selection” is to formulate some generalrules which can be used in the eco-design process when dealing with composites, withoutperforming an exhaustive LCA. These general rules are summarized in a matrix. This matrixmethod results in a indication of the relative environmental impact. This method can assistdesigners in making decisions regarding environmental aspects, when they have to choosebetween functionally equivalent materials.

From the results and experience dealing with LCA, a general ranking in aspects which have animpact on the LCA results is given below in descending order of importance:

1. energy consumption2. production3. material use4. waste/recycling5. packaging

It is well known [Marissen, 1993] [ Goedkoop, 1995] from environmental assessments of manyproducts, that when during the use phase energy or material input takes place this phase isdominant. From these products it is known that the environmental impact is not determined bythe production phase or the disposal phase but by its use and design should be directed towardsefficient operating/use. On the other hand when for instance 80% of energy consumption for theproduct takes place in the material production phase, effort should focus on a design for materialrecycling strategy.

From the previous study [Haperen and Haije, 1997] we may draw the conclusion that theenvironmental impact during the life-cycle of a composite (e.g. coated steelplate) is determinedby the longevity of the composite.

Based on the aforementioned ‘rules’ one can compose a matrix with the most importantclassification factors: the production-, use- and disposal phase. Based on general experience thedesigner can fill in this matrix. Special care should be taken when hazard and toxic materialsplay a goal. Within each life cycle phase we can judge for each possible composite materialwith the same function, it’s environmental impact with a minus sign, zero (neutral) or plus sign

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product applicationmaterial: composite x composite y composite zproduction phase*:-energy requirementuse phase*:-longevity-energy consumption-maintenancedisposal*:-landfill-combustion-recyclingTotal:

* Special care should be taken when hazard and toxic materials play a goal.

After adding the vertical colums the designer obtains a relative indication of the environmentalimpact. Incorporating of a weighing factor for each phase may refine this model. Based on thisrelative indication the designer can decide to choose for the most environmental sound optionwhen he has to make a choise between two or more materials, without performing tedious LCAexercises.

We can illustrate this method with two examples. The first example deals with three differentcoatings. PVC, PUR and polyester applied on a steelplate, which were subject of the previousstudy [Haperen and Haije, 1997].

product application: coating on a steelplatematerial: PVC PUR polyesterproduction phase:- energy requirement

_0 0

use phase:- longevity- energy consumption- maintenance

+ ++ +

disposal:-landfill-combustion-recycling

0 0 0

Total: 0 2+ +

Filling in this matrix indicated that a steelplate with a PUR coating is the best option from anenvironmental point of view, due to the longevity of a PUR coating on a steelplate.

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The second example deals with the three composite rotorblades which were subject of thisstudy.

product application: rotorblade (inc. steel)material: flaxfibre rotorblade carbonfibre rotorblade glassfibre rotorbladeproduction phase:- energy requirement 0 - -use phase:- longevity- energy consumption- maintenance

0 0 0

disposal:-landfill-combustion-recycling

0 0 0

Total: 0 -1 -1

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6. DISCUSSION

When we mutually compare the three types of fibre reinforced composites, in order to make anhonest environmental comparison we have to determine what the influence of the amount ofsteel applied in each rotorblade is. In table 6.1 the eco-indicator of one m3 composite is given.The composition of a typical composite is 70 w% fibre and 30 w% resin [Lee,1991].

Table 6.1 Eco-indicator of one m3 composite

Composite Eco-indicatorcarbonfibre reinforced composite 11.8flaxfibre reinforced composite 6.6glassfibre reinforced composite 3.4

In table 6.1 we can see the impact of the application of the product. In this case theenvironmental impact of the production of carbonfibre is larger, as compared to the other twocomposites due to the energy consumption needed for carbonfibre production. In the case of theglassfibre reinforced rotorblade half the eco-indicator is determined by the amount of steelapplied in the rotorblade. From an environmental point of view we can conclude that forapplication in for instance a container, a glassfibre reinforced composite may be preferred, andin a rotorblade application a flaxfibre reinforced composite may be preferred.

The consulted sources are considered as reasonably reliable. Only for some of the materials nodata was available and therefore they are estimated on the bases of comparable materials.Regarding the production of pesticides no data was available. According to a study of IMSA[Oegema, 1994] this is justified by the fact that the emissions during pesticide production areneglected compared to the emissions during the use of pesticides.

It is also important to note that weighing factors have a subjective nature. Therefore one shouldbe careful in drawing far-reaching conclusions.

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7. CONCLUSIONS

• Based on the results of this LCA study the environmental impact of the three fibre reinforcedrotorblades are of the same order of magnitude. The eco-indicator of the flaxfibre reinforcedrotorblade was slightly lower (1.8) than the others (2.4).

• It is important to keep in mind that the environmental impact is determined by the productsfunction during its lifetime.

• The environmental impact of a product turns out to be determined in general by the amountof energy used in the three phases of the life cycle.

• From the study concerning different coatings on a steelplate [Haperen and Haije, 1997] wemay draw the conclusion that the environmental impact during the life-cycle of a composite(coated steelplate) is determined by the longevity of the composite.

• In this study we present an outline of a method which results in a relative indication of theenvironmental impact of a composite material, whithout performing an exhaustive LCA. Themethod can assist designers in making decisions regarding environmental aspects. Themethod is not intended to push aside the Life Cycle Assessment method.

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8. RECOMMENDATIONS

Performing an LCA is a tedious job. From the present and a previous study [Haperen and Haije,1997] it is clear that it must be possible to refine the “choice matrix” model to a working toolthat can easily be incorporated in software packages. Keeping track of performed comparativeLCA studies in literature may help in this fine-tuning process.

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REFERENCES

1. Biekart J.W., Nigten A., Stopplenburg D., Duurzame Chemie, 1997.2. Communication Mr. T. v.d. Wekken, Lagerwey.3. Communication Mrs.P.Doelman, Ceres BV.4. Fleckenstein, H., Wirtschaftlichkeitsbetrachtung fuer ein Standardprodukt aus

Faserverbundwerkstoff im Vergleich zu Stahl, VDI-Z ,Vol. 125, pp. 123-131, 1983.5. Fritz H.G., Seidenstücker T., Bölz U., Juza M., Production of Thermo-Bioplastics and

Fibres based mainly on Biological Materials, European Commision report EUR 16102 EN,1994.

6. Goedkoop M.J.,The Eco-indicator 95,NOH report 9523; Pré Consultants; Amersfoort (NL),1996.

7. Goedkoop M.J., Manual Simapro 3,Pré Consultants; Amersfoort, 1995.8. Goedkoop M.J., Ecodesign experience with Hylite, Pré Consultants; Amersfoort, 1995.9. Haperen J. van, Haije W.G., Milieubewuste materiaalkeuze: mono-versus niet mono-

materialen, januari 1997, ECN-I-97-001.10. Haije W.G., Evaluatie van de mogelijkheden voor recycling van windturbinebladen, Petten,

ECN-Energie Engineering 6206-GR1, juni 1994.11. Heijungs R. et al., Achtergronden Milieugerichte Levenscyclusanalyses van

produkten,Leiden, Centrum voor milieukunde, NOH rapport 9253, 1992.12. Kok I.C., Milieugerichte levencyclusanalyses van windturbines, februari 1996, ECN-C-95-

050.13. Kortekaas, S., Augustijn, M. and Nigten, A. ‘Preliminary investigation of flax, LMO,

Utrecht, 1991.14. Lee S.M., Jonas T., Disalvo G., The beneficial energy and environmental impact of

composite materials- an unexpected bonus, SAMPE Journal, vol. 27, No. 2, 1991.15. Marissen R., Some Environmental Aspects of the application of FRPs in Structures, Delft

University of Technology, 1993, Delft.16. Oegema T., Postma G., Rapportage Biodiesel, Milieuanalyse, Economie van de bedrijfstak,

IMSA, 1994.17. Overbeek, J.P., LCA van windturbinebladen, ECN---96-xxx18. Potting, J., Blok, K., Life-cycle assessment of four types of floor covering, J.Cleaner Prod.,

Vol. 3, No. 4, pp.201-213, 1995.19. Pesink B.J., Ven van der B.L., Hooftman R.N., Palsma A.J., LCA Smeermiddelen,

publicatiereeks productenbeleid nr.1996/18.20. Remmerswaal, Idemat 1996, TU-Delft.21. Tempelman E., Design for Sustainability: the Advent of Hybrid Materials, Delft University

of Technology, 1994, Delft.22. Worrel, E, Heijningen, R.J.J, Castro de, J.F.M., Hazewinkel, J.H.O., Beer, de J.G., Faaij,

A.P.C., Vringer, K., New gross energy-requiremenents figures for material production,Energy, Vol. 19, (6) pp. 627-640, 1994.

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APPENDIX A ECO INDICATOR

Table A.1 Eco-indicator 95 impact categories and their weighing factors (source [Goedkoop,1996])

Environmental effect Weighingfactor

Criterion

Greenhouse effect 2.5 0.1°C rise every 10 years, 5% ecosystem degradationOzone layer depletion 100 Probability of 1 fatality per year per million inhabitantsAcidification 10 5% ecosystem degradationEutrophication 5 Rivers and lakes, degradation of an unknown number of aquatic

ecosystems (5% degradation)Summer smog 2.5 Occurrence of smog periods, health complaints, particularly

amongst asthma patients and the elderly, prevention of agriculturaldamage

Winter smog 5 Occurrence of smog periods, health complaints, particularlyamongst asthma patients and the elderly

Pesticides 25 5% ecosystem degradationAirborne heavy metals 5 Lead content in children’s blood, reduced life expectancy and

learning performance in an unknown number of peopleWaterborne heavy metals 5 Cadmium content in rivers, ultimately also impacts on people (see

airborne)Carcinogenic substances 10 Probability of 1 fatality per year per million people

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APPENDIX B IMPACT TABLE

SimaPro 3.1M ----------- Substances -----------Date: 09/10/97Method: SimaPro 3.0 Eco Ind.

Carbonfibre Glassfibre FlaxfibreSubstance Un. Rotor bl. Rotor bl. Rotor bl.

category: Raw materialair kg 19.0 41.0 6.06azodicarbonamide g 0 60 0barrage water ton 42.2 3.27 6.89bauxite (ore) g 267 149 141blast-furnace gas MJ 82.3 332 6.05boron oxide (B2O3) kg 1.30 22.3 1.30CaF2 kg 0.087 1.48 0.087clay g 7.31 6.52 2.59coal kg 252 266 174cobalt g 500 43.1 500coke breeze kg 3.51 16.0 3.51copper (ore) kg 683 0 683crude oil g 0 0 477derived gases MJ 3.02 0.205 3.02energy from hydro power MJ 14.0 0 12.7energy from uranium MJ 359 0 324feldspar kg 0.435 7.44 0.435ferro-manganese mg 35 0 35flotation agent g 19.7 0 19.7glass cullet kg 1.14 0 1.14hydrochloric acid g 360 153 360iron (ore) kg 80.6 368 80.6K2O (potassium oxide) kg 0 0 0kaolinite (chinaclay) kg 0 1.18 0land use m2 7.41 0 6.69lignite kg 44.1 0.147 3.93lime kg 1.82 0 1.82limestone mineral kg 32.2 198 32.2magnesia (MgO) kg 0 0 0methylene chloride kg 0 90 0natural gas m3 765 524 411natural gas kg g 0 0 28.6nitrogen kg 0 5.19 0oil kg 332 217 124organic compounds kg 0 0 0other energies MJ 19.9 91.2 19.9oxygen m3 4.22 19.3 4.22oxylime sludge kg 1.25 5.74 1.25peroxide g 150 0 150rock salt kg 31.7 58.9 30.4sand g 12.2 3.01 12.2secondary fuels MJ 95.1 435 95.1silane kg 0 0 0

34 ECN-I--97-050

silica kg 13.0 161 13.0steel g 759 0 759steel scrap kg 9.71 44.4 9.71unspecified energy kWh 127 459 113uranium ore? kg 2.59 0.751 0.847water kg 1608 647 1255wood kg 8.39 6.96 8.26zinc-poor residue kg 0.259 1.18 0.259

category: Airborne emissionacetone kg 0.112 2.97 0.112

Al mg 69.1 316 69.1aldehydes mg 472 1.47 67.3ammonia g 0.294 6.93 5.51As mg 4.76 21.8 4.76B2O3 g 42.0 719 42.0benzene g 36.4 1.53 36.5benzo[a]pyrene mg 12.7 55.9 12.7Ca g 0.811 3.71 0.811Cd mg 17.2 79.0 17.3Cl2 g 0.833 2.66 0.833CO kg 3.16 11.1 2.56CO2 kg 1673 1389 911cobalt mg 2.27 0.09 602.27Cr mg 5.91 27.0 6.01Cu mg 72.9 43.2 69.2CxHy kg 3.49 2.89 1.51CxHy aliphatic g 910 48.3 910CxHy aromatic kg 1.32 0.0665 1.31CxHy chloro g 15.9 2.80 15.9deltamethrin mg 0 0 815dichloromethane kg 0.000174 30.0 0.000174dioctyl phthalate (DOP) g 0 23.7 0dust (coarse) kg 0.905 1.19 0.432dust (SPM) mg 495 0 605epichlorohydrin g 65.7 2.77 65.7ethylbenzene mg 0 0 46.3Fe g 3.84 17.5 3.84fluoranthene mg 33.8 154 33.8fluorine g 15.2 32.0 15.2formaldehyde g 0.159 2.80 0.225formic acid (CH3OH) mg 0 631 0H2 g 33.0 7.13 0.00163H2S g 8.17 26.1 5.99HCl g 72.8 16.8 64.3HCN mg 32.8 149 32.8HF mg 38.2 3.39 35.1KCl g 11.6 53.2 11.6manganese mg 162 741 162mercury mg 12.9 19.4 11.4metals mg 730 311 512methane kg 2.60 2.68 1.82methyl ethyl ketone g 131 5.54 131Mg mg 88.8 406 88.8N2 g 0 6 0

ECN-I--97-050 35

N2O g 43.1 53.7 67.7naphthalene mg 0 0 7.94nickel mg 4.46 20.4 4.46non methane CxHy g 132 0 119NOx kg 6.32 5.02 3.71organics (other) mg 237 9.41 18.7parathion mg 0 0 827Pb g 0.570 2.46 0.570Pb-210 kBq 1.04 4.78 1.04pentane mg 0 0 165phenol g 1.80 2.30 1.80phosphoric acid (H3PO4) mg 0 2.34 0Po-210 kBq 1.04 4.78 1.04radioactive substances kBq 78151 0 70641SO2 kg 5.83 3.23 3.33soot g 17.3 0 2.64SOx kg 0.0432 1.20 0.0441styrene kg 1.05 0.455 1.05toluene g 6.35 0.267 6.54V mg 782 0 707vinylchloride kg 0 0 0VOS g 50.5 180 50.5

Zn g 0.336 1.15 0.335

category: Waterborne emissionacid g 27.9 52.5 13.2Acid as H+ g 7 0 7Ag æg 23.2 396 23.2ammonia g 1.13 0.192 0.778anorg. suspended subst. g 35 0 35base g 0 36.2 0BOD g 12.3 5.77 5.82Ca kg 0 0 0Cd mg 0.418 1.97 0.418Cl2 kg 2.99 0.401 2.82cobalt kg 0 0 0COD kg 4.74 0.259 4.70cooling water m3 14.3 70.7 14.3Cr mg 6.09 27.9 6.09Cu mg 10.7 49.0 10.7CxHy g 23.3 24.0 7.15CxHy aliphatic g 17.5 0 17.5CxHy aromatic g 0.757 1.86 0.684CxHy chloro mg 118 11.2 118deltamethrin g 0 0 3.78di-amine (R1R2NH) g 0 2.38 0dichloromethane kg 0 0 0dissolved organics g 40.7 11.7 33.2dissolved substances g 187 188 94.0E-glass polymer coating g 34.8 595 34.8Fe g 7.66 35.7 7.66fluorine g 0.961 5.33 0.372formaldehyde mg 0 46.8 0

H2 mg 0 0 13.8Hg mg 0.401 4.17 0.401

36 ECN-I--97-050

Kjeldahl N g 19.3 74.0 17.2linuron g 0 0 1.51

MCPA mg 0 0 472metallic ions g 115 98.5 71.1Na g 971 284 971NH4+ g 1.85 1.52 0.763Ni mg 6.42 33.5 6.42nitrate g 0.446 0.303 570Ntot æg 0 0 463oil g 60.6 36.1 32.4other g 4.59 21.4 4.59PAH mg 1.61 7.40 1.61parathion g 0 0 4.57Pb mg 11.4 54.8 11.4Pb-210 Bq 10.8 49.7 10.8peroxide kg 0 0 0phenol mg 700 105 412phosphate mg 0.928 15.8 0.928Po-210 Bq 21.3 97.6 21.3process water l 0 176 0quarry water l 1.16 19.8 1.16radioactive substances kBq 722 0 653S g 1.18 0.0155 0.0938SO4 kg 1.25 0.265 1.15suspended substances g 128 62.0 78.2treated water m3 0.0721 2.76 0.0721Zn g 2.27 0.308 2.05

category: Solid emissionCaF6 (nw) mg 720 221 33.7epoxy resin kg 8.52 0.52 8.52fiber E-glass kg 0.1 12.1 0.1final waste (inert) kg 51.8 0 46.8firestone kg 0 0 0fly ash (tw) g 184 545 87.0glass kg 0.174 2.97 0.174Hg mg 47.5 30.1 21.7high active nuclear waste cm3 11.1 3.37 0.651industrial waste g 106 10.9 105low,med. act. nucl. waste cm3 36.7 0.844 30.8mineral waste kg 4.32 2.03 2.95non-toxic chemicals kg 2.12 0.257 1.90polyester resin kg 0 22 0produc. waste (not inert) kg 3.03 0 2.74PUR g 0 200 0PVC kg 0 0 0PVC foam kg 0 1 0secondary suction dust g 15.9 73.1 15.9Silex kg 0 0 0slag kg 1.18 0.777 0.710steel g 150 150 150

tailings g 17.4 51.7 8.25toxic chemicals g 157 13.3 157unspecified waste kg 5.74 16.1 5.60

ECN-I--97-050 37

wood kg 1.32 1.32 1.32zinc-rich residue g 180 824 180