WALiD LCA Handbook

Comparative Life CycleAssessment of WALiD Technologies and Processes Handbook www.eu-walid.com The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement number 309985

First published in 2017 by Smithers Rapra and Smithers Pira Ltd Shawbury, Shrewsbury, UK, SY4 4NR © Smithers Rapra and Smithers Pira Ltd., 2017 All rights reserved. Except as permitted under current legislation no part of this publication may be photocopied, reproduced or distributed in any form of by any means or stored in a database or retrieval system, without the prior permission from the copyright holder.Every effort has been made to contact copyright holders of any material reproduced within the text and the author and publishers apologise if any have been overlooked. Typeset by S. Hall Typesetting & Graphic Design

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookContents1. Introduction 1 1.1 WALiD Blade 1 1.1.1 Blade Root 2 1.1.2 Blade Tip 2 1.1.3 Shell Core 3 1.1.4 Shear Web 3 1.1.5 Spar Cap 3 1.1.6 Coating 42. Goal and Scope of the Study 5 2.1 Goal of the Study 5 2.2 Scope of the Study 5 5 2.2.1 Functional Unit 6 2.2.2 System Boundaries 7 2.3 Impact Assessment Method 7 2.3.1 Midpoint Level 9 2.3.2 Endpoint Level 103. Life Cycle Assessment - Materials 10 3.1 Blade Root 11 3.2 Blade Tip 12 3.3 Shell Core 14 3.4 Shear Web 15 3.5 Spar Cap 16 3.6 Coating 17 3.7 Whole Blade 17 18 3.7.1 Midpoint Analysis 19 3.7.2 Endpoint Analysis 3.7.3 Global Warming Potential 214. End of Life 21 22 4.1 Powder Impression Moulding (PIM) 4.2 Retaining Walls

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook 24 25 4.3 3D Printing 26 4.4 Decking 27 4.5 Railway Sleepers 27 4.6 Use of Existing Blade Structure 4.7 Future Recommendations 295. Conclusions and Recommendations 30References

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook IntroductionSecurity, sustainability and economic prosperity are together the energy trilemma that we face(International Energy Agency, 2014). The use of new and renewable energy sources and thedevelopment of cleaner and efficient energy technologies will play an important role in solving thistrilemma. Over recent years, renewable energy sources have achieved greater significance as a partof the energy mix for the major EU economies. Among these renewable energy sources, wind poweris currently one of the fastest-growing sources of electricity globally (International Energy Agency,2016).Amongst wind power installations, the most productive installations (measured by average numberof hours of operation at full capacity) are those which are installed offshore. The NEEDS (DongEnergy, 2008) project compared annual production of the same 2MW turbine installed in an offshoreand onshore wind farm. Electricity production (in MWh.yr) of the offshore installation was 8088,compared with the onshore installation of 5634. This equates to a 43% productivity benefit for anoffshore installation. Further, the historic success of onshore wind energy has led to a shortage ofsuitable land sites in many parts of Europe.Europe continues to dominate the offshore wind sector and approximately 90% of global capacity iswithin Europe. As of 30 June 2016, there are 3344 offshore wind turbines with a combined capacityof 11538 MW fully grid connected in European waters in 82 wind farms across 11 countries (WindEurope, 2016). A report by the European Wind Energy Association (EWEA) (EWEA, 2015) predictsthree wind energy scenarios for 2030, showing the expected growth in offshore wind energy. Thelow, central and high scenarios expect 7439, 11081 and 16346 offshore wind turbines to be installedin Europe by 2030 respectively.Wind energy is a clean technology during its operational phase as it generates electricity from arenewable source without producing any waste or using any mineral or water resources. However, ina life cycle perspective there are non-renewable resource demands and harmful emissions associatedwith it. These environmental and resource pressures can be quantified and assessed by the methodof life cycle assessment (LCA).The study contained in this handbook uses LCA to examine, in detail, the differences in life cycleimpact between a current state of the art offshore wind blade and the newly designed WALiD blade.1.1 WALiD BladeThe power generated by offshore wind turbines is dependent on the rotor plane area of the blade.The major issue is that due to the weight of larger blades, the materials used suffer considerablestrain, which reduces the amount of time they are operational. Additionally, the blades have tobe adapted to more challenging environmental off-shore conditions such as corrosive and humidenvironments with high temperature variations and high load conditions. Using current state of theart materials these limits cannot be overcome.The WALiD project has combined process, material and design innovations in an integrated approach.The core innovation aimed to use advanced thermoplastic composites. This creates cost-effective, 1

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbooklightweight, durable and recyclable 90m offshore blades with beneficial weight/performance ratio,making wind energy more affordable and competitive.As in conventional blade design, the main structural components are the upper and lower shells thatare connected to each other at the leading and trailing edge. Inside, two shear webs keep the shellsat the designated distance. To achieve an appropriate bending stiffness spar caps are utilised in bothshells. Finally, the whole blade is covered by a coating to protect the blade from environmentalinfluences.1.1.1 Blade Root Figure 1: Blade root and tipThe blade root is the part of the blade which bears the highest loads and makes up a high proportionof the weight. The main function of the blade root is the transmission of the load from the blade tothe hub. The connection concept determines the way the load is transferred between the compositestructure of the blade and the metallic structure of the hub.State of the art blades are commonly constructed using thermoset materials and fixed to the hubwith a T-bolt connection. As the blade root connection needs to be reliable throughout the wholelifetime of the blade, high safety factors are taken into account. This leads to wall thicknesses of upto 160mm in the laminate structure, which results in an additional weight of the blade root.By reducing the wall thickness of the laminate in the root section it is possible to reduce theweight and the required composite materials of the blade root. A novel blade root concept usingthermoplastic material has been developed within the WALiD project which achieves this withoutaffecting the transfer of the required loads.The idea is to use a steel insert with a waved curvature, which is directly connected to the hub.Tapes have been produced with mechanical properties beyond the current state of the art. Hybridyarns are used as raw material for tape production and trials have been carried out on the adhesionof the polymers and fibres. During the process the tapes are heated on a pultrusion line to melttemperature and then positioned in a defined layer to obtain the best adhesion of fibres and polymer.They are then processed and cooled to fuse the layers together before being wound onto a reel.These unidirectional thermoplastic tapes are directly placed on the metal insert using an automatedfibre placement process and fixed by thermoplastic belts. The belts also consist of unidirectionaltapes. The new connection concept makes it possible to transfer the load from the blade to the hubwithout the need of a bolt connection. This, in turn, allows a reduction of the laminate thickness inthe root section as the continuous fibre structure is not locally damaged by drilling holes into thelaminate.1.1.2 Blade TipThe blade tip, as the part which is furthest away from the hub, has to withstand particular mechanicalrequirements. The high rotational speed of a wind turbine blade tip leads to high mechanical stresses.Initial discussions about improvements to the blade tip concluded that in contrast to state of the arttip sections of blades, the developed blade tip within this project will consist of a tailored compositestructure made from thermoplastic tapes. The tape lay-up in the automated fibre placement (AFP)2

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbookprocess enables a tailored design according to the load requirements of the blade tip. This allowsthe exploitation of the lightweight construction potential in the tip area of the blade, which is of highimportance as a reduction in weight of parts sited away from the hub decreases the stress in thewhole blade structure.1.1.3 Shell Core Figure 2: Shell coreFor the shell core, new modified thermoplastic polymer blends were used to produce tailoredproperties for the foamed material. In addition, new polymers and additives for polymeric foamsin a continuous extrusion process were investigated and the materials characterised. This has ledto new ultra-light and stiff foam materials produced using a cost-effective manufacturing process.1.1.4 Shear Web Figure 3: Shear webThe purpose of the shear web is to keep the geometrical distance between the spar caps, ensuringthe overall bending stiffness of the blade.Currently, wind blades are manufactured using glass fibre and/or carbon fibre reinforced thermosets,balsa wood and PVC foams. Processes used include wet hand layup, thermoset impregnated filamentwinding, prepreg technology and resin infusion technology. There are a number of disadvantages tothese processes including the emission of volatile organics during processing, long cycle times dueto the curing process, poor resistance against environmental conditions resulting in a decrease ofmechanical properties, an increase in weight and a lack of reproducibility and recyclability.WALiD has developed a new lightweight design for the shear web connecting the two outer shells ofthe wind blade and has replaced the thermoset materials with a framework of new materials. Thesenew materials consist of thermoplastic composites and foams which are processed using automatedfibre placement and winding.The thermoplastic materials used are cost-effective and have a high level of recyclability. Also, theuse of foam has been optimised to reduce scrap.1.1.5 Spar CapCurrently, spar caps are manufactured with reinforcement fibres and thermoset materials such asepoxy, vinyl ester and thermoset polyester and are manufactured using resin infusion technology orconsolidation of prepreg systems. 3

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookWALiD has developed a new concept to produce the spar caps. Automated fibre placement is carriedout using a specially adapted robot. Unidirectional tapes and thermoplastic materials have beenused in order to give strength, stiffness and rigidity to the structure and reduce weight.1.1.6 Coating Figure 4: CoatingOffshore wind turbines operate under harsh conditions and are subject to abrasion, fouling, ice andin particular, erosion of the leading edge by droplet impingement wear. The thermoset coatings usedin state of the art blades are difficult to recycle and are not lightweight.WALiD has developed a reinforced thermoplastic coating with anti-icing properties and durabilityagainst abrasion to improve environmental resistance, which can lead to reduced maintenancecosts.4

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Goal and Scope of the Study2.1 Goal of the StudyThe move towards sustainable development requires a paradigm shift from a fractured view of theenvironment, with the emphasis on one stage of the life cycle, to a more holistic life cycle approachto environmental management. LCA is a tool that enables and supports such a paradigm shift as itembodies life cycle thinking and so provides a full picture of human interaction with the environment.The application of this LCA study is the comparison of the overall environmental impacts associatedwith the new thermoplastic based technologies developed within the WALiD project with equivalentwind turbine blades based on current technology.The blade developed in the WALiD project was designed to be 90m in length. Therefore, to allowa comparison to take place, the inputs and outputs of the current state of the art wind blade thatis studied in this LCA have been scaled up to represent a 90m blade. In this handbook, “#2-Blade”refers to #2-Blade with Carbon Spar-Cap and “#3-WALiD Blade” refers to the blade developed in theWALiD project.By identifying the steps within the life cycle which have the most significant impact on the environment,environmental management efforts can be directed effectively. The early results from the screeninganalysis were used by the consortium to inform the material selection process, and to evaluate andmitigate environmental impact hotspots of the thermoplastic materials approach, compared to thetraditional and almost universally adopted use of epoxy based thermosetting materials.The International Standards ISO 14040/44 provides an indispensable framework for life cycleassessment. These standards, in conjunction with the best practice as described in the InternationalReference Life Cycle Data System (European Commission JRC Institute for Environment andSustainability, 2010) were used to guide all analyses conducted as part of the WALiD LCA activities.2.2 Scope of the Study2.2.1 Functional UnitThe functional unit of 1 kw/h, delivered to the grid will be used.The function of any power generation plant is to generate electricity. Hence the functional unitshould be an amount of generated electricity.The operational lifetime of 25 years will be used.This is longer than the 20 year lifetime used for most existing LCA studies. A longer lifetime of 25 yearsis reflective of the experience of Vestas. The Danish company has the largest market share of anyturbine maker, and began manufacturing industrial scale turbines in 1979. Vestas’ experience is thatoperational lives in excess of 30 years are regularly achieved. Further to this, for the type of investmentand installation cost, the larger offshore turbines should be expected to have a longer lifetime. 5

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook2.2.2 System BoundariesIn this study, the cradle-to-grave life cycles of the wind turbine blades were to be investigated. Thecradle-to-grave approach evaluates all stages of the wind blade’s life from raw material productionto end of life management. Energy and material inputs are traced back to the extraction ofresources, and emissions and wastes from each life cycle stage are quantified. The result is a lifecycle inventory (LCI). The LCA evaluates all stages of the blade’s life from the perspective that theyare interdependent, meaning that one operation leads to the next. The system boundaries in thisLCA are presented in Figure 5 and the stages are as follows:• MaterialsThis stage comprises the raw material production and supply of other components that are deliveredin their various forms to the factory where the blades are manufactured. Any alteration of the rawmaterials will be considered in this step, for example, addition of nanomaterials to polymers, formingof unidirectional composite tapes, production of polymeric foams, and the manufacture of coatingswill be included within this stage of the LCA.• Blade manufactureThis step includes the materials preparation and assembly, integration of the blade to the hub fixings,and application of the coating to form a finished blade.• Transport and installationThis stage takes into account the transfer of the finished components from their various placesof manufacture to the wind farm site, and their placement and fixing into their place in the windturbine structure.• OperationThe operation phase deals with the general running and maintenance of the blades as the turbinesgenerate electricity during their 25 year lifetime.• DismantlingThe decommissioning (or repowering) of the wind farm, and the return of the dismantled componentsto shore.• Recycling or end of life disposal of the components. Figure 5: Illustration of system boundaries6

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookThe analysis in this LCA study focuses on the materials stage of the life cycle. This is due to a lackof data for the other stages. End of life options have been investigated and are presented in thishandbook in chapter 4.2.3 Impact Assessment MethodA life cycle inventory has been developed to demonstrate a complete map of all inputs and outputs ofthe WALiD wind blade. SimaPro software was used as the principal evaluation tool for the calculationof the environmental impacts. The current edition being used at Smithers Rapra is 8.0.2. To makeit possible to successfully compare blades using different materials and processes, all the data hasbeen obtained by asking partners within the consortium, the industry or seeking information onscientific publications, LCA reports and datasheet of materials. Some data is used from the Ecoinventdatabase. The Ecoinvent database was selected to provide background data to estimate quantities ofinputs and outputs for different unit processes within the system. The database is used extensivelyby LCA practitioners throughout Europe.The impact assessment method ReCiPe was employed in this study to transform the long list ofconsumed resources and emissions into impact category indicators. The results obtained in theclassification phase are multiplied by the characterisation factors of each substance within eachimpact category. These indicator scores express the relative severity on an environmental impactcategory. It integrates and harmonises in a consistent framework:• Eighteen midpoint indicators• Three endpoint indicators2.3.1 Midpoint LevelMidpoint impact category, or problem-orientated approach, translates impacts into environmentalthemes (this LCA uses the Hierarchist perspective):• Climate ChangeClimate change can result in adverse effects upon ecosystem health, human health and materialwelfare. Climate change is related to emissions of greenhouse gases to air. Gases contributing tothe greenhouse effect are aggregated according to their impact on radiative warming compared tocarbon dioxide as the reference. Therefore, impacts are expressed in kg CO₂ equivalents.• Ozone DepletionThe characterisation factor for ozone layer depletion accounts for the destruction of the stratosphericozone layer by anthropogenic emissions of ozone depleting substances (ODS). Impacts are expressedas kg CFC-11 equivalents.• Terrestrial AcidificationTerrestrial acidification is characterised by changes in soil chemical properties following thedeposition of nutrients (namely, nitrogen and sulphur) in acidifying forms. Acidification potential isexpressed as kg SO₂ equivalents.• Freshwater EutrophicationThe characterisation factor of freshwater eutrophication accounts for the environmental persistenceof the emission of phosphorous (P) containing nutrients. The unit is kg P to freshwater equivalents.• Marine EutrophicationThe characterisation factor of marine eutrophication accounts for the environmental persistence ofthe emission of nitrogen (N) containing nutrients. The unit is kg N to freshwater equivalents. 7

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook• Human ToxicityThis category concerns effects of toxic substances on the human environment. Human ToxicityPotentials (HTP) are expressed as kg 1,4-DB (dichlorobenzene) equivalent.• Photochemical Oxidant FormationPhotochemical oxidant formation is the formation of reactive substances (mainly ozone) which areinjurious to human health and ecosystems and which also may damage crops. The characterisationfactor of photochemical oxidant formation is defined as the marginal change in the 24h-averageEuropean concentration of ozone due to a marginal change in emission of substance x. The unit iskg NMVOC.• Particulate Matter FormationThe characterisation factor of particulate matter formation is the intake fraction of PM₁₀. The unit iskg PM₁₀ equivalents.• Terrestrial EcotoxicityThis category refers to impacts of toxic substances on terrestrial ecosystems, as a result of emissionsof toxic substances to air, water and soil. The unit is kg 1,4-DB equivalents.• Freshwater EcotoxicityThis category refers to impacts of toxic substances on freshwater ecosystems, as a result of emissionsof toxic substances to air, water and soil. The unit is kg 1,4-DB equivalents.• Marine EcotoxicityThis category refers to impacts of toxic substances on marine ecosystems, as a result of emissions oftoxic substances to air, water and soil. The unit is kg 1,4-DB equivalents.• Ionising RadiationThe characterisation factor of ionizing radiation accounts for the level of exposure. The unit is kgUranium-235 (U-235) equivalents.• Agricultural Land OccupationThe amount of agricultural land occupied for a certain time. The unit is m²a.• Urban Land OccupationThe amount of urban land occupied for a certain time. The unit is m²a.• Natural Land TransformationThe amount of natural land transformed and occupied for a certain time. The unit is m².• Water DepletionThe factor for water depletion is water consumption. The unit is m³.• Metal DepletionThis impact category is concerned with protection of human welfare, human health and ecosystemhealth. The characterisation factor for metal depletion is the decrease in grade. The unit is kg Iron(Fe) equivalents.• Fossil DepletionThis impact category is concerned with protection of human welfare, human health and ecosystemhealth. This impact category indicator is related to extraction of fossil fuels due to inputs in thesystem. The unit is kg oil equivalents.8

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook2.3.2 Endpoint LevelEndpoint impact category, also known as the damage-orientated approach, translates environmentalimpacts into three issues of concern:• Human Health: Effect of environmental changes to human health expressed as the number of years of life lost and the number of years lived disabled. These are combined and measured in Disability-Adjusted Life Years (DALYS).• Ecosystems: Expressed as the loss of species over a certain area, during a certain time. The unit is years.• Resources: Expressed as the surplus costs of future resource production over an infinitive timeframe (assuming constant annual production), considering a 3% discount rate. The unit is 2000US$.These three endpoint categories are weighted using the ReCiPe endpoint assessment method withhierarchist weighting to generate single-score values expressed in kpt (thousands of eco-points) foraverage yearly impact of one European citizen.In this study, both midpoint and endpoint assessments have been conducted. Figure 6 shows therelationship between midpoint and endpoint indicators and where the single score results arecoming from. Figure 6: Relationship between LCI parameters (left), midpoint indicator (middle) and endpoint indicator (right) (Source: Goedkoop et al, 2008). 9

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Life Cycle Assessment - MaterialsThis chapter shows the impact assessment results for the materials stage of the life cycle. Results inthis chapter will show comparisons between the two blades in six components; the blade root, bladetip, shell core, shear web, spar cap and the coating, and also the blade as a whole.3.1 Blade RootAs the WALiD blade root has a new design and concept it is interesting to observe its impact comparedto the current concept.Table 1 shows the characterised results from the midpoint method. The #3-WALiD Blade has higherpotential environmental impacts across 10 of the 18 indicators compared to the #2-Blade. In the #3-WALiDBlade root the quantity of metals used is six times higher than in the #2-Blade because of the metal insert.This explains why the impact category metal depletion is far greater for the #3-WALiD Blade. Table 1: Characterised results of the root (midpoint method)Impact category Unit #2-Blade with Carbon #3-WALiD Blade spar capClimate change kg CO₂ eq 69830.507 51925.386Ozone depletion kg CFC-11 eq 0.003 0.004Terrestrial acidification kg SO₂ eq 389.074 242.809Freshwater eutrophication kg P eq 1.658 2.255Marine eutrophication kg N eq 13.534 6.734Human toxicity kg 1,4-DB eq 23824.079 20896.874Photochemical oxidant formation kg NMVOC 355.087 177.095Particulate matter formation kg PM₁₀ eq 183.711 111.947Terrestrial ecotoxicity kg 1,4-DB eq 3.712 4.317Freshwater ecotoxicity kg 1,4-DB eq 19.663 10.780Marine ecotoxicity kg 1,4-DB eq 41.428 82.296Ionising radiation kBq U-235 eq 9740.449 12818.604Agricultural land occupation m²a 331.851 688.808Urban land occupation m²a 181.116 323.918Natural land transformation m² 5.930 8.081Water depletion m³ 131949.306 328813.549Metal depletion kg Fe eq 6289.014 28614.577Fossil depletion kg oil eq 24387.420 19607.888Figure 7 shows the potential impacts of the two blade roots at the endpoint level. It shows no greatdifferences between the two blades overall, however there is a higher potential impact on humanhealth and ecosystems from the #2-Blade and higher impacts on resources from the #3-WALiD Blade.This higher impact on resources is because of the metal insert as explained previously.10

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Figure 7: Comparison of the root (endpoint method)3.2 Blade Tip Table 2: Characterised results of the tip (midpoint method)Impact category Unit #2-Blade with #3-WALiD Blade Carbon spar capClimate change kg CO₂ eq 292.074 168.357Ozone depletion kg CFC-11 eq 0.000 0.000Terrestrial acidification kg SO₂ eq 1.632 0.772Freshwater eutrophication kg P eq 0.007 0.006Marine eutrophication kg N eq 0.057 0.022Human toxicity kg 1,4-DB eq 100.189 69.671Photochemical oxidant formation kg NMVOC 1.495 0.570Particulate matter formation kg PM₁₀ eq 0.755 0.267Terrestrial ecotoxicity kg 1,4-DB eq 0.015 0.013Freshwater ecotoxicity kg 1,4-DB eq 0.082 0.034Marine ecotoxicity kg 1,4-DB eq 0.147 0.150Ionising radiation kBq U-235 eq 40.496 43.069Agricultural land occupation m²a 1.263 1.832Urban land occupation m²a 0.681 0.726Natural land transformation m² 0.025 0.028Water depletion m³ 417.806 446.915Metal depletion kg Fe eq 9.115 10.453Fossil depletion kg oil eq 102.426 68.381As shown in Table 2, blades with thermoplastic tapes (#3-WALiD Blade) rather than thermosetmaterials (#2-Blade) in the tip provide lower potential environmental impacts for 11 of the 18midpoint impact categories. 11

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookFigure 8 presents the potential environmental impacts of the two blade tips at the endpoint level.The potential impacts on all three categories of resources, ecosystems and human health are lowerfor the #3-WALiD blade. Figure 8: Comparison of the tip (endpoint method)3.3 Shell CoreTable 3 shows the potential environmental impacts at the midpoint level of the shells for the twocomparing blades. The potential environmental impacts of 13 of the 18 categories are higher for the#2-Blade than the #3-WALiD Blade.Figure 9 shows the potential environmental impacts of the shell core of the two blades at theendpoint level. The difference between the material inputs in the tip and the shell of the #3-WALiDBlade is the addition of foam in these data. By comparison to Figure 8, Figure 9 confirms that thefoam does not contribute greatly to a difference in the proportion of the potential endpoint impacts.The shell of the #3-WALiD Blade has lower potential environmental impacts than the shell of the#2-Blade at the endpoint level. The greatest reduction from the WALiD blade at this level is humanhealth. All the midpoint indicators that contribute to human health endpoint category have higherpotential impacts from the #2-Blade.12

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookTable 3: Characterised results of the shell (midpoint method)Impact category Unit #2-Blade with #3-WALiD Blade Carbon spar capClimate change kg CO₂ eq 24919.449Ozone depletion kg CFC-11 eq 45087.041 0.002Terrestrial acidification 0.002Freshwater eutrophication kg SO₂ eq 111.012Marine eutrophication kg P eq 208.564 1.026Human toxicity kg N eq 0.905 3.124Photochemical oxidant formation kg 1,4-DB eq 7.614Particulate matter formation kg NMVOC 9558.445Terrestrial ecotoxicity kg PM₁₀ eq 12156.504 82.563Freshwater ecotoxicity kg 1,4-DB eq 199.637 38.747Marine ecotoxicity kg 1,4-DB eq 95.191 2.092Ionising radiation kg 1,4-DB eq 1.967 7.854Agricultural land occupation kBq U-235 eq 11.505 27.228Urban land occupation 21.376Natural land transformation m²a 6470.004Water depletion m²a 10598.404 290.971Metal depletion m² 300.281 107.138Fossil depletion m³ 86.816 kg Fe eq 4.087 4.050 kg oil eq 67200.262 193727.185 1568.091 1131.863 10373.765 16441.535Figure 9: Comparison of the shell (endpoint method) 13

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook3.4 Shear WebTable 4 shows the potential environmental impacts at the midpoint level for the shear web of thetwo blades. It shows there are the same number of midpoint categories with higher potential impactfrom both the #2-Blade and the #3-WALiD Blade. However, the endpoint results presented belowin Figure 10 show how these impacts can contribute to resources, ecosystems and human health. Table 4: Characterised results of the shear web (midpoint method)Impact category Unit #2-Blade with #3-WALiD Blade Carbon spar capClimate change kg CO₂ eq 13172.676 7678.177Ozone depletion kg CFC-11 eq 0.001 0.001Terrestrial acidification kg SO₂ eq 59.867 34.182Freshwater eutrophication kg P eq 0.285 0.320Marine eutrophication kg N eq 2.482 1.290Human toxicity kg 1,4-DB eq 3193.894 2509.475Photochemical oxidant formation kg NMVOC 57.134 26.085Particulate matter formation kg PM₁₀ eq 26.442 11.618Terrestrial ecotoxicity kg 1,4-DB eq 0.525 0.565Freshwater ecotoxicity kg 1,4-DB eq 3.237 2.332Marine ecotoxicity kg 1,4-DB eq 5.804 7.446Ionising radiation kBq U-235 eq 2944.978 1716.457Agricultural land occupation m²a 83.044 77.814Urban land occupation m²a 22.955 28.443Natural land transformation m² 1.104 1.072Water depletion m³ 54979.305 17849.076Metal depletion kg Fe eq 297.928 416.586Fossil depletion kg oil eq 4828.621 3164.274 Figure 10: Comparison of the shear web (endpoint method)14

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookCompared to the tip and the shell, the shear web is made of tapes, foams and glue. By comparingwith Figure 8 and Figure 9, Figure 10 shows the addition of glue does not contribute greatly to adifference in the proportion of the potential impacts.The potential environmental impact on all three endpoint categories is lower for the #3-WALiDBlade than the #2-Blade. All midpoint indicators that contribute to the concern of human healthhave a lower potential impact for the #3-WALiD Blade. Lower potential impacts are achieved for themidpoint categories of climate change, terrestrial acidification and freshwater ecotoxicity for theWALiD blade. These have contributed to a lower potential environmental impact on ecosystems.The higher fossil depletion of the #2-Blade has caused the higher impact on resources for thisblade.3.5 Spar CapTable 5 presents the characterised results comparing the potential environmental impacts of thespar cap for the #2-Blade and the #3-WALiD Blade at the midpoint level. The #3-WALiD Blade isshown to lead to lower potential impact across 12 of the 18 indicators.Table 5: Characterised results of the spar cap (midpoint method)Impact category Unit #2-Blade with #3-WALiD Blade Carbon spar capClimate change kg CO₂ eq 247435.147Ozone depletion kg CFC-11 eq 317434.837 0.012Terrestrial acidification 0.013Freshwater eutrophication kg SO₂ eq 854.871Marine eutrophication kg P eq 1254.180 3.807Human toxicity kg N eq 3.504 38.344Photochemical oxidant formation kg 1,4-DB eq 56.972Particulate matter formation kg NMVOC 25493.396Terrestrial ecotoxicity kg PM₁₀ eq 34013.670 656.157Freshwater ecotoxicity kg 1,4-DB eq 1072.565 264.881Marine ecotoxicity kg 1,4-DB eq 475.942 641.112Ionising radiation kg 1,4-DB eq 758.613 201.447Agricultural land occupation kBq U-235 eq 253.164 9958.398Urban land occupation 11770.732Natural land transformation m²a 68334.337 64059.538Water depletion m²a 1259.680 1528.879Metal depletion m² 344.507 400.427Fossil depletion m³ kg Fe eq 11.483 14.251 kg oil eq 137707.458 184043.924 3108.261 4477.956 116358.326 96471.648Figure 11 shows the potential environmental impacts of the spar cap of the two blades at the endpointlevel. As can be seen in Figure 11, the choice of thermoplastic material in the spar cap achieves adecrease in the overall environmental impacts when compared to the material in current state ofthe art blades. The tapes in the spar cap of the #3-WALiD blade are made of different thermoplasticfibres to those in the tip. Figure 11 displays the differences between the potential impacts of thespar cap and the tip when compared with Figure 8.As with the tip and the shell, all midpoint categories that contribute to impacts on human healthhave higher potential impacts for the #2-Blade. 15

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Figure 11: Comparison of the spar cap (endpoint method)3.6 CoatingTable 6 shows the characterised results of the coating of the two blades under study at the midpointlevel. The coating of the WALiD blade is the only part which does not contain similar materials to theparts described above. The thermoplastic coating in the WALiD blade provides the lowest potentialenvironmental impact for 15 of the 18 midpoint impact categories compared with current materialsin the #2-Blade. Table 6: Characterised results of the coating (midpoint method)Impact category Unit #2-Blade with #3-WALiD Blade Carbon spar capClimate change kg CO₂ eq 3803.585 1268.303Ozone depletion kg CFC-11 eq 0.000 0.000Terrestrial acidification kg SO₂ eq 24.379 5.961Freshwater eutrophication kg P eq 0.096 0.132Marine eutrophication kg N eq 0.783 0.194Human toxicity kg 1,4-DB eq 309.430 47.301Photochemical oxidant formation kg NMVOC 22.441 5.302Particulate matter formation kg PM₁₀ eq 12.674 2.098Terrestrial ecotoxicity kg 1,4-DB eq 0.080 0.029Freshwater ecotoxicity kg 1,4-DB eq 1.208 0.029Marine ecotoxicity kg 1,4-DB eq 1.199 0.536Ionising radiation kBq U-235 eq 97.502 70.606Agricultural land occupation m²a 10.051 10.392Urban land occupation m²a 3.549 3.851Natural land transformation m² 0.165 0.068Water depletion m³ 1355.736 1261.224Metal depletion kg Fe eq 33.908 27.307Fossil depletion kg oil eq 1444.708 760.71216

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookFigure 12 shows a large difference between the potential impacts of the coating of the two bladesat the endpoint level. It is possible to observe that each endpoint category (resources, ecosystemsand human health) of the #3-WALiD Blade has only one third of the impact of the #2-Blade. Allmidpoint indicators that lead to the endpoint categories of human health and resources have ahigher potential environmental impact from the #2-Blade. Figure 12: Comparison of the coating (endpoint method)3.7 Whole BladeThis chapter provides an analysis of the LCA results for the materials stage taking into account alldata from the two blades.3.7.1 Midpoint AnalysisTable 7 shows the characterised results of the two blades at the midpoint level. The #3-WALiD Bladeprovides lower potential environmental impact across 12 of the 18 midpoint impact categoriescompared to the #2-Blade.Figure 13 shows 12 of 18 categories have 100% of impact for the #2-Blade compared to the #3-WALiDBlade. The six categories at 100% for the #3-WALiD Blade are freshwater eutrophication, agriculturalland occupation, urban land occupation, natural land transformation, water depletion and metaldepletion. All of these categories mentioned are related to land, agriculture and water except formetal depletion, which is due to the insert. The other categories have been related to the “Esterfamily”. Some of these polymers are biodegradables and may have impact on the environment atthe end of life. 17

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Table 7: Characterised results of the two blades (midpoint method)Impact category Unit #2-Blade with #3-WALiD Blade Carbon spar capClimate change kg CO₂ eq 451026.509 332900.329Ozone depletion kg CFC-11 eq 0.020 0.019Terrestrial acidification kg SO₂ eq 1942.037 1247.305Freshwater eutrophication kg P eq 6.440 7.526Marine eutrophication kg N eq 81.299 49.644Human toxicity kg 1,4-DB eq 73823.214 58379.718Photochemical oxidant formation kg NMVOC 1711.338 946.091Particulate matter formation kg PM₁₀ eq 796.797 428.487Terrestrial ecotoxicity kg 1,4-DB eq 767.078 648.086Freshwater ecotoxicity kg 1,4-DB eq 289.550 222.615Marine ecotoxicity kg 1,4-DB eq 11874.684 10075.259Ionising radiation kBq U-235 eq 92563.521 85056.950Agricultural land occupation m²a 2014.087 2592.066Urban land occupation m²a 646.654 861.395Natural land transformation m² 23.097 27.473Water depletion m³ 523331.099 596430.413Metal depletion kg Fe eq 10911.245 34834.792Fossil depletion kg oil eq 163969.940 130258.753 Figure 13: Comparison of the two blades (midpoint method)3.7.2 Endpoint AnalysisTable 8 and Figure 14 show the potential environmental impacts of the #2-Blade and the #3-WALiDblade at the endpoint level.18

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookTable 8 and Figure 14 both show the lower impact of the #3-WALiD Blade compared to the #2-Blade.Even though the #3-WALiD Blade has a much more accurate database, the impact is still lower thanthe #2-Blade. These midpoint and endpoint results show that using the materials and processesdeveloped in the WALiD project minimises the potential environmental impact on resources,ecosystems and human health at the materials stage compared to current state of the art. Table 8: Characterised results of the two blades (endpoint method)Label Human Health Ecosystems Resources#2 – 90m Blade with Carbon Spar-Cap 17.661 8.325 18.127combined#3 90m WALiD Blade 12.273 6.251 15.618 Figure 14: Comparison of the two blades (endpoint method)3.7.3 Global Warming PotentialWhen determining the climatic impact of a substance, the Global Warming Potential (GWP) is used.This is a measure of the effect on radiation of a particular quantity of the substance over time relativeto that of the same quantity of CO₂. The GWP depends thus on the time spent in the atmosphereby the gas, and on the gas’s capacity to affect radiation, which describes the immediate effectson overall radiation of a rise in concentration of the gas. The GWP is calculated with combinedclimatic and chemical models and covers two effects: the direct effect a substance has through theabsorption of infrared radiation and the indirect chemical effects on overall radiation.The GWP of the #2-Blade and the #3-WALiD Blade has been analysed for the materials life cyclestage. Figure 15 and Figure 16 display the network of the GWP for each blade which shows wherethe impacts are coming from. Figure 15: Network of the Global Warming potential of the #2-BladeFigure 15 shows that 83% of the impact from the #2-Blade is from carbon fibre (56.2%) and epoxyresin (27.2%). Carbon fibre has a very high impact compared to glass fibre. Figure 16: Network of the Global Warming potential of the #3-WALiD Blade 19

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookFrom Figure 15 and Figure 16 a comparison can be made between the materials contributing to GWPin the two blades. The difference in materials and their contribution to GWP for the #2-Blade andthe #3-WALiD Blade are as follows; “epoxy resin” (27.2%) and “thermoplastic 1” (17%), “gel coat”(1.11%) and “coating” (0.66%), “PVC foam- Divinycell” (3.36%) and “foam” (1.49%), but mostly theimpact is coming from the fibres: “carbon fibre” (56.2%) and “fibre 2” (64.1%) respectively.20

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook End of LifeThis handbook has highlighted the growth in the European wind industry, in terms of both thenumber of turbines and their sizes. In addition, a growing number of wind turbines are to bedecommissioned, due to the fact that the lifetime of a wind turbine is approximately 20-25 years andthere are increased opportunities for replacing old models with newer and more efficient machines.Therefore, a sustainable process to deal with the turbines at the end of their life is needed in orderto maximise the environmental benefits of wind energy through a lifecycle approach. Most parts ofa wind turbine such as foundation, tower, components of the gear box and generator are alreadyrecyclable and treated accordingly with an average recyclability for a wind turbine between 80 to85%. However, wind blades represent a challenge for waste management due to the complexity oftheir composition and materials used (Welstead, J., Hirst, R., Keogh, D., Robb G. and Bainsfair, R.,2013).At the moment, there are three possible routes for dismantled wind turbine blades: incineration,landfill or recycling.Incineration is the most common disposal option. The advantage is that there are already numerousfacilities in place and that the process can be carried out competitively. However, 60% of the scrapis left behind as a potentially pollutant ash (Larsen, 2009) that needs to be placed in landfill. Theinorganic loads also lead to the emission of hazardous flue gasses that can cause problems in theflue gas cleaning system.Landfill is a common disposal option for wind turbine blades due to their complicated compositeconstruction. However, EU legislation discourages the disposal of waste to landfill and compositematerials are likely to be banned from landfill in future European policies due to their high organiccontent.Recycling is the alternative route for the end of life of wind turbine blades. However, there arelimited potential end uses and end markets for the thermoset materials in current state of the artblades, making recycling of the composites challenging. The thermoset material will not melt but willeventually degrade at high temperatures or it may be attacked by certain chemicals. Reprocessing toform other plastic artefacts is therefore exceedingly difficult. Recycling routes are usually based onthe total destruction of the blades with most going to the cement industry as filler material.The blade developed in the WALiD project however was designed with a thermoplastic matrix toincrease the potential for recyclability. Since the blades would be a constant source, the recyclatewould be expected to have better consistency than most recyclate. Potential end uses forthermoplastic wind turbine blades have been investigated and some are explained below.4.1 Powder Impression Moulding (PIM)This process, developed by Environmental Recycling Technologies plc (ERT), can manufacturelightweight sandwich structures from 100% mixed post-consumer polymer. Recycled plastic by-products are milled into controlled powder blends that can then be moulded using PIM moulding 21

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbooktechnology. The process has exceptionally high tolerance to feedstock variations (contamination,dissimilar materials and particle size) and could therefore be a uniquely effective recycling technologyfor dealing with the complex composition and materials of the WALiD wind turbine blade.An example of a product manufactured using the PIM technology is shown in Figure 17. BrownwaterPlastics LLC holds an exclusive license from ERT to manufacture and sell barge covers and othermarine products that are made using the PIM process. The barge covers (that measure 200ft² -possibly the world’s largest thermoplastic moulding) are a superior product to existing fibre glassbarge covers and can be recycled at end of life. Figure 17: Barge covers made using the PIM process (Source: Plastics Recycling Expo, 2014)4.2 Retaining WallsTraditionally made from concrete (prone to cracking) or timber (prone to rotting); retaining wallshold back soil where natural slopes are being resisted to gain maximum flat land. Alternatively 100%recycled mixed polymer can be used. Ecocrib is one company in the UK who manufacture retainingwalls entirely from recycled UK plastic waste. It creates durable (they will not rot or be affected bywater or fungus infection), robust, economic and sustainable retaining walls. Ecocrib claim no wasteis created during the manufacture or installation with all surplus material re-processed to form newEcocrib profiles, and when the retaining system reaches the end of its useful life the Ecocrib profilescan be recycled again. Certified by the British Board of Agrément (BBA), Ecocrib can achieve a designlife greater than 120 years.22

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Figure 18: Kettering A14 retaining wall using 100% recycled plastic (Source: Ecocrib, n.da)Figure 19: Retaining wall using 100% recycled plastic in Crick, Northamptonshire (Source: Ecocrib, n.dc) 23

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Figure 20: Retaining wall using recycled plastic at Center Parcs, Woburn Forrest (Source: Ecocrib, n.db)The Ecocrib retaining walls have been installed across the UK including 1800sqm used on the A14J7-9 Kettering Bypass. This project (shown in Figure 18) has diverted 160 tonnes of plastic waste fromlandfill. Figure 19 shows part of a project in Crick, Northamptonshire where 140 tonnes of plasticwaste has been diverted from landfill to manufacture its 1576sqm retaining wall. Finally, Figure 20shows part of an Ecocrib retaining wall at Center Parcs in Woburn Forrest which used 75 tonnes ofrecycled plastic waste.Ecocrib uses plastic from bags, packaging, car bumpers and bottle tops, but these examples show theenormous scope possible with recycled polymers that could become a potential end of life use forthe thermoplastic materials in the WALiD blade.4.3 3D PrintingMaterials recovered from recycled WALiD wind blades could potentially be used as the material for3D printing. 3D printing with thermoplastics is widely practiced and may be the only choice for manyapplications. Figure 21 is one example of a product made with a thermoplastic material.24

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Figure 21: An example of a complex item produced using thermoplastics (L), and its baseplate (R) (Source: Flite Club, 2016)4.4 DeckingRecycled plastic has been used for many years to create benches, bollards and fencing (two examplesare shown in Figure 22) and is a potential option for thermoplastic wind turbine blades. Figure 22: Recycled plastic bench and fencing (Source: Hahn Plastics Ltd, 2016)The use of the recycled plastic as a structural material, however, would require a greater volumeof recycled material which could be an ideal use for the decommissioned WALiD blades. AcrossEurope, more and more recycled plastic walkways or boardwalks are being developed and installedby a range of organisations (examples in Figure 23). This more cutting edge use has similar benefitsto the retaining walls described in chapter 4.2, including durability, low maintenance, resistance toUV light, vandal resistance, resistance to rot, splinter-proof and the recycled plastic products arecompletely recyclable at the end of their useful lifespan. No preservative is required therefore itcomplies with the requirements restricting the use of copper chromium arsenate. Also, recycledcomposite materials are completely inert and will not leach any chemicals into water or soil even inwet conditions. These walkways and boardwalks are also chosen because they are better value thantheir timber alternatives, whilst still blending harmoniously with the environments they protect. 25

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Figure 23: Recycled plastic walkway and boardwalk (Source: Hahn Plastics Ltd, 2015)4.5 Railway SleepersRailway sleepers are another example of how large quantities of waste thermoplastics are beingused for structural building materials. The most commonly used materials of wood or concrete arebecoming less favourable for sleeper manufacturers. This is in response to the European ban on theuse of creosote treatment from 2018, the high maintenance of wood and its reduced quality, thehigh weight of concrete sleepers and the fact that these can easily crack.According to one manufacturer Lankhorst Engineered Services, Netherlands, the plastic sleeper hashigh end properties and retains these properties during its long expected lifespan of over 50 years.This is compared to 25-30 years for creosoted oak sleepers and 10 years for untreated oak sleepers. Figure 24: Railway sleepers made using recycled plastic (Source: Lankhorst Mouldings, 2016)26

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook4.6 Use of Existing Blade StructureUnlike the other examples in this chapter representing how thermoplastic wind turbine blades canbe recycled, this final example is re-use with minimal disruption to the existing structure. Bladeshave been transformed into park benches, seats and children’s playground items by clever use ofthe existing blade structure. Figure 25: The Wikado Playground in Rotterdam, Netherlands. (Source: Superuse Studios, 2014)An example is shown above in Figure 25. The Wikado Playground located at a grade school inRotterdam, Netherlands is a sustainable playground designed by Superuse Studios. Built in 2012,the entire outdoor play area is a safe playground which uses five old wind turbine blades which werecut up, reassembled and welded to create a cost efficient and fun place for the children. Portions ofthe park include tunnels, towers, slides and even benches and seating for parents to eat and rest.Making use of entire wind turbine blades, the Dutch company has also successfully designed andbuilt seating in Rotterdam and a bus shelter in Almere Poort.These projects demonstrate the technical applications and potential for whole blade designsand architecture. These blade designs are durable, iconic, compete economically and reduce theecological footprint of projects in which they are used (Superuse Studios, 2014).When whole blade structures are used they could play an additional valuable role as above-ground,in-use, composite material storage. In this way valuable composite material could be recovered laterfrom such structures when economic and environmentally viable recovery or recycling methods areestablished. Benefits not achieved when composites are sent to permanent disuse in landfill or areincinerated.4.7 Future RecommendationsIt is clear that end of life options for composite wind turbine blades is an increasing issue and landfillis becoming an unacceptable method of waste disposal. 27

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookCurrently, the materials in the WALiD blade provide options for recyclability. This project shows thatindustry is waking up to the challenge, not only in terms of recycling, but also in terms of researchinto new materials.A problem exists however, because the wind industry is relatively young, there is only a limitedamount of practical experience in the recycling of wind turbine blades, particularly offshore, and itwill take time to gain this practical experience in the dismantling, separation, recycling and disposalof thermoplastic wind turbine blades. It is recommended that future work be carried out intoresearch, industry and policy.Further study is needed into the ease of dismantling the WALiD blade without compromising theperformance of the materials. Currently, the potential uses identified in this chapter are largely onesthat use the whole blade. However, higher value re-use may be possible and more potential uses couldbe provided if the materials can be easily separated. Also, degradation of the blade would need to beinvestigated to determine the quality of the materials at the end of life. Applications for the recyclatecan then be selected, for example moving the materials down the chain of importance. These pointsreiterate the importance of focusing on sustainable design and sustainable manufacturing effortsearly in the wind blade development process.With the amount of waste expected from wind turbine blades, further investigations are needed asto whether the infrastructure is in place to exploit the opportunities to recycle. Individual companiesthat assume responsibility for their waste management suffer, under certain circumstances, fromthe economies of scale and transportation costs that exist in waste management. Also, the mostimportant business consideration is whether there is an end market demand for the recyclate(Reynolds, N and Pharaoh, M, 2010). The examples in this chapter have shown the possibilities forrecycled thermoplastic wind turbine blades, but a considerable amount of work will be required todevelop and establish these routes. It makes sense to develop a recycling industry to maturity beforethe amount of waste reaches a high level.There is currently little legislation in place for the regulation of end of life waste management for thewind industry in Europe. Appropriate legislative measures that support the entire recycling processcould stimulate the growth needed.28

Comparative Life Cycle Assessment of WALiD Technologies and Processes Handbook Conclusions and RecommendationsThe goal of comparing the overall potential environmental impacts associated with the newthermoplastic based technologies developed within the WALiD project, with equivalent wind turbineblades based on current technology has been fully achieved through this study for the materials lifecycle stage.The materials stage is important in the life cycle of the wind turbine blades. Although there arecomponents with potential environmental impact within the WALiD blade, it is evident from thisLCA study that the thermoplastic materials chosen for the WALiD blade lead to lower potentialenvironmental impacts compared to existing offshore wind blade technologies and materials.The results in chapter 3 show that except for the WALiD blade root’s impact on resources, the newthermoplastic based technologies developed in the WALiD project have lower impact on resources,ecosystems and human health for all parts of the blade compared with the parts of an equivalentoffshore wind turbine blade based on current technology.Recycling thermoplastic materials in wind turbine blades remains a challenge due to both technicallimitations and lack of legislation. The examples in chapter 4 however have shown the vast uses forrecycled thermoplastic materials in a wide variety of sectors. These options show that it is possibleto create new products using waste plastic whose properties could be as good as, if not outperformsimilar products, made using virgin materials. But one thing is clear, for wind turbine blades to beused in these ways they need to be made using thermoplastic materials.This life cycle assessment could further benefit from analysis of other life cycle stages. It is worthinvestigating the manufacturing process in depth to compare impacts at this stage and also to findopportunities to improve energy efficiency. The potential for lightweight construction with thethermoplastic materials could have an influence on the transport and installation stage, and theoperation stage could be considered to assess the maintenance of the blades with different coating.Adding life cycle assessment to the decision-making process provides an understanding of thehuman health and environmental impact that traditionally is not considered when selecting aproduct or process. This valuable information provides a way to account for the full impacts ofdecisions, especially those that occur outside of the site that are directly influenced by the selectionof a product or process. As LCA is a tool to better inform decision-makers it should be included withother decision criteria to make a well-balanced decision. A life cycle cost analysis has therefore beenconducted along with this LCA. 29

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookReferencesDong Energy. (2008). Life Cycle Approaches to assess emerging energy technologies. FP6 project NEEDS.Ecocrib. (n.da). A14 Kettering Bypass J7-9. [Online]. Available at http://www.ecocribwall.co.uk/case.html?id=14 [Accessed 12 December 2016].Ecocrib. (n.db). Centreparcs, Woburn Forest. [Online]. Available at http://www.ecocribwall.co.uk/case. html?id=12 [Accessed 12 December 2016].Ecocrib. (n.dc). Finnegans, Crick. [Online]. Available at http://www.ecocribwall.co.uk/case.html?id=12 [Accessed 12 December 2016].European Commission JRC Institute for Environment and Sustainability. (2010). ILCD Handbook. Luxembourg: Publications Office of the European Union.European Wind Energy Association. (2015). Wind energy scenarios for 2030. Wind Europe.Flite Club. (2016). TILT Racing Drone full 3D printed kit. [Online]. Available at http://www.fliteclub.com.au/ product/tilt-racing-drone-full-3d-printed-kit-incl-pdb/ [Accessed 13 December 2016].Goedkoop M.J., Heijungs R., Huijbregts M., De Schryver A., Struijs J. and Van Zelm R. (2012). ReCiPe 2008, A life cycle impact assessment method which comprises harmonised category indicators at the midpoint and the endpoint level; First edition Report I: Characterisation.Hahn Plastics Ltd. (2015). Recycled Plastic Decking. [Online]. Available at http://www.hahnplastics.com/ uploads/redactor/Newmillerdam%20Recycled%20Plastic%20Decking.compressed_02_12_2015.pdf [Accessed 14 December 2016].Hahn Plastics Ltd. (2016). New Recycled Plastic Product Catalogue. [Online]. Available at http://www. hahnkunststoffe.de/media/pdf/6a/c7/20/HAHN_Katalog_2016_DE_EN_oP_web.pdf [Accessed 14 Dec 2016].International Energy Agency. (2014). 2013 Annual report, Technical report. International Energy Agency.International Energy Agency. (2016). Next Generation Wind and Solar Power from cost to value. International Energy Agency.Lankhorst Mouldings. (2016). Plastic Sleeper. [Online]. Available at http://www.lankhorstrail.com/en/rail- sleepers [Accessed 13 December 2016].Larsen, K. (2009). Recycling wind turbine blades. Renewable Energy Focus. Elsevier Ltd. 9 (7), 70-73.Plastics Recycling Expo. (2014). Brownwater Plastics case study. [Online]. Available at http://www. plasticsrecyclingexpo.com/uploads/exhibitor/PTR68175/productpdf/ert-case-studies-2014-1.pdf [Accessed 13/12/2016].Reynolds, N., Pharaoh, M. (2010). An introduction to Composites Recycling. Management, Recycling and Reuse of Waste Composites. Woodhead Publishing Limited, Cambridge. 3-19.Superuse Studios. (2014). Blade Made. https://issuu.com/2012architecten/docs/blademade?utm_ source=tester&utm_campaign=161c50bf82-Frisse_Wind&utm_medium=email&utm_ term=0_448d3290c5-161c50bf82-Welstead, J., Hirst, R., Keogh, D., Robb G. and Bainsfair, R. (2013). Research and guidance on restoration and decommissioning of onshore wind farms. Scottish Natural Heritage Commissioned Report No. 591.Wind Europe. (2016). The European offshore wind industry, key trends and statistics 1st half 2016. Wind Europe.30

Comparative Life Cycle Assessment of WALiD Technologies and Processes HandbookPartnersThe research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013 under grant agreement number 309985 31