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The rapid increase in the wind energy sector has brought forward a challenging problem of disposing off a huge quantity of non-biodegradable, thermosetting fibre reinforced polymer (FRP) composite materials used in wind turbine blades. Most of the existing solutions are either not sustainable or not economical. This study focuses on re-use options. In this paper a design option for re-using decommissioned wind turbine blades in pedestrian bridges is presented. To demonstrate the concept, an 8.5 m long pedestrian bridge is designed using parts taken from two A29 (modified version of Vestas V27) windblades. A preliminary code-based structural analysis is carried out to assess practicality of the proposed design and to check strength and serviceability requirements given in the prescribed codes. The results show that proposed design full-fills the strength criteria and serviceability requirements recommended in the Eurocodes. The maximum strength utilisation of the blade components is found about 61% and deflection is limited to span/303. 

The rapid growth in wind energy technology has led to an increase in the amount of thermosetting FRP composite materials used in wind turbine blades that will need to be recycled or disposed of in the near future. Calculations show that 4.2 million tons of waste from wind blades will need to be managed globally by 2035, increasing to 16.3 million tons by 2055. Three waste management route are possible: disposal, recycling or reusing. Currently, most FRP composites taken out of service are disposal of in landfills or are incinerated. Recycling options consist of reclamation of the constituent fibers or the resins by thermo–chemical methods or recycling of small pieces of granular FRP material as filler material by cutting, shredding or grinding. Reuse options consist of reusing the entire FRP blade or large parts of the blade in new structural applications. This paper reports on the potential for reusing parts of wind turbine blades in new or retrofitted architectural and civil infrastructure projects. The paper introduces the geometry, materials, and laminates typically used in wind blades and provides a snapshot of the sizes of wind blades likely to be available from the inventory of active turbines. Because the materials and manufacturing of commercial wind blades are proprietary, generic blade geometries and materials are discussed. These come from the Sandia National Laboratory and National Renewable Energy Laboratory, in the United States, and from OPTIMAT in the European Union. The paper presents a method for generating the geometry and material properties of structural elements cut from wind blades, using the Numerical Manufacturing and Design Tool (NUMAD), published by the Sandia National Laboratory. 

Recycling glass fiber reinforced polymer (GFRP) composite materials has been proven to be challenging due to their high mechanical performance and high resistance to harsh chemical and thermal conditions. This work discusses the efforts made in the past to mechanically process GFRP waste materials by cutting them into large-sized (cm scale) pieces, as opposed to pulverization, for use in concrete mixtures. These pieces can be classified into two main categories—coarse aggregate and discrete reinforcement, here referred to as “needles.” The results from all the studies show that using GFRP coarse aggregate leads to significant reductions in the compressive strength and tensile strength of concrete. However, GFRP needles lead to sizable increases in the energy absorption capacity of concrete. In addition, if the glass fibers are longitudinally aligned within the needles, these elements can substantially increase the tensile strength of concrete. Processing GFRP waste into needles requires less energy and time than that for producing GFRP coarse aggregate. Also, compared to pulverized GFRP waste, which consists of broken and separate particles of glass and resin that at best can be used as low-quality fillers, GFRP needles are high strength composite elements 

The very rapid growth in wind energy technology in the last 15 years has led to a rapid growth in the amount of non–biodegradable, thermosetting FRP composite materials used in wind turbine blades that will need to be managed of in the near future. A typical 2.0 MW turbine with three 50 m blades has approximately 20 tonnes of FRP material and an 8 MW turbine has approximately 80 tonnes of FRP material (1 MW ~ 10 tonnes of FRP). Calculations show that 4.2 million tonnes will need to be managed globally by 2035 and 16.3 million tonnes by 2055 if wind turbine construction continues at current levels and with current technology. Three major categories of end-of-life (EOL) options are possible – disposal, recovery and reuse. Reuse options are the primary focus of this paper since landfilling and incineration are environmentally harmful and recovery recycling methods are not economical. The current work reports on different architectural and structural options for reusing parts of wind turbine blades in new or retrofitted housing projects. Large-sized FRP pieces that can be salvaged from the turbine blades and potentially useful in infrastructure projects where harsh environmental conditions (water and high humidity) exist. Their noncorrosive properties make them durable construction materials. The approach presented is to cut the decommissioned wind turbine blades into segments that can be repurposed for structural and architectural applications for affordable housing projects. The geographical focus of the designs presented in this paper is in the coastal region of the Yucatan on the Gulf of Mexico where low quality masonry block informal housing is vulnerable to severe hurricanes and flooding. In what follows, a prototype 100m long wind blade model provided by Sandia National Laboratories is used as a demonstration to show how a wind blade can be broken down into parts, thus making it possible to envision architectural applications for the different wind blade segments.