CAN WIND TURBINES BE RECYCLED?
There is a misconception that wind turbines are environmentally harmful because of their components and that, for this reason, they are impossible to recycle. This is wrong: about 96 per cent of a wind turbine is recyclable. To understand this, one can look at the composition of such a technology.
Shell, shafts, gearing and electrical components, a wind turbine is made up of more than 8,000 parts. But to make it simple we can divide it in four parts, each with specific functions and the therefore materials:
- The foundations, buried in the ground, are made of concrete and scrap metal.
- The tower, which needs to support the nacelle and provides access to it, is essentially made of steel.
- Going up we find the nacelle, which houses the system to convert the wind’s mechanical energy into electricity and is therefore mainly constituted by electrical components.
- And finally, the rotor – hub and blades – made of a polymer resin reinforced with fiberglass and occasionally carbon fibre.
If we relate these materials to the tonnage of the wind turbine, we find that almost 90 per cent of it is steel and cement, six per cent is fibreglass, only three per cent are polymers and the rest are metals and electronic materials. Most of it is therefore fully recyclable. In 2021 the recycling rate of wind turbines in France, excluding the blades, approached 98 per cent (96 per cent with the blades).
While the concrete can be crushed, sorted and recycled as aggregate for other types of concrete, in particular for other wind turbines, or as fill, and steel can be recycled over and over without any loss of property,
that is not the case for the blades. At present, blades are the hard nut of wind turbine recycling. The problem with blades is the way they are built. Fibreglass is composed of fine strands of plastic and glass, which makes them hard and costly to recycle.
According to estimates, 1GW is expected to be dismantled annually in France by 2025, which means 3,000 to 15,000 tonnes of composite materials per year. The issue of the recycling of composite materials is not unique to the wind power industry, the same materials being used by the automotive, shipping and leisure industries for aeronautical parts, boats’ hulls and even skis, but it is often used to discredit the sustainability of this renewable energy. Although blades are inert and do not produce toxic emissions – being therefore quite safe for landfills – their uncontrolled disposal remains a huge waste of resources that moves away from sustainability and circularity criteria. There is no denying that a lot of first-generation blades end up in landfills – but not in Europe, where burying wind turbine blades is strictly prohibited – however that’s not the case for all of them.
Manufacturers and operators are focusing on new approaches, trying to find ways to separate the polymer matrix from the reinforcing fibres to recover and reuse the materials, or rebuild new blades using recyclable materials. Wind blades can thus be entirely repurposed as structural elements such as playgrounds, bike shed, noise barriers or parts of civil engineering projects. They can be recycled in a mechanical way, shredded, and often reused as filler material in buildings: a process Veolia, the French resource management company, masters using crushed blade materials as an ingredient for cement production. They can be treated thermally, incinerated, and revalorised as fuel for energy production, and – in few
cases – they can also undergo a chemical process where the fibres are separated from the resins by means of solvents and thermal processes.
That is what Vestas, the Danish wind turbine manufacturer, is working on, testing a cutting-edge technology which breaks down blades in a liquid using inexpensive, non-toxic, and readily available chemicals, which allows to produce high quality materials using little energy.
Other initiatives are looking at modifying the materials used to make turbines, with the aim of designing a new generation of blades made from thermoplastics that are either biodegradable or can be reconstituted at the end of their useful life, making the blades more sustainable to manufacture and easier to recycle. That is the case of the first fully recyclable blades that the ZEBRA (Zero wastE Blade ReseArch) consortium has worked on, producing them in LM Wind Power’s Ponferrada factory in Spain, before testing and marketing them in Denmark.
There is always room for improvement, particularly by keeping working on the eco- design of components. This 100 per cent recyclable blade is an important step and a promising breakthrough that can help achieve an increased sustainability in the wind energy sector, while waiting to create a highly efficient supply chain capable of recycling and upgrading all components.
Needless to say, even if today the wind turbines current form may not be perfect, their positive environmental impact far outweighs the negative ones on the overall life cycle.
This article was published by the Energy Observer Productions team and is republished here with our thanks.
THE REPORT | SEP 2024 | ISSUE 109 | 129
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148
