Recycling of Retired Materials
Product recyclability continues to be a challenge to the composite industry due to the nature of these materials. We are actively working toward sustainable end-of-life solutions for composite products and identifying alternative pathways to landfill through the development of new materials and process technologies that enable greater recyclability through both in-house research and with external partners.
TPI offers decommissioning services to wind blade owners. We are working to develop equipment to provide cost-effective methods to reduce the transport cost of decommissioned wind blades. This work is done in collaboration with waste management companies, government funded activities, university research and consortia that include Europe’s Horizon 2020, the U.S. DOE sponsored Institute for Advanced Composite Manufacturing Innovation, and the National Science Foundation WindSTAR I/UCRC. We also conduct independent research and development focusing on a variety of technologies that support a sustainable circular economy.
Research efforts include the identification of industries and applications that will benefit from use of the output created from end-of-life process technologies as feedstocks for new products. One example explores harvesting thermal energy from wind blade resin core materials for firing cement kilns and using the soda ash generated from glass fibers to displace significant amounts of mined products for the manufacturing of the cement materials. This approach may avoid millions of metric tons of CO2 emissions generated in conventional kiln operations and provides a viable alternative to landfill disposal for end-of-life wind blades. These efforts bring true value and enable a sustainable circular economy for the products we manufacture and the materials that we use as well as offering the entire wind industry services for wind blade decommissioning and disposition.
Longer term solutions include significant efforts in the characterization of new liquid resin systems along with process development and component demonstration of these innovative plastics. These materials have been shown by TPI and others to create composite materials that perform as well as, or better than, current thermosetting epoxies, but provide a low energy pathway to depolymerization. This will allow for recovery of reinforcements (glass fiber, carbon, and core) with minimal impact on their properties and provide feedstocks for new resin and molding compounds thus creating a truly circular economy and providing a bright future for retired composite products.
Waste by Disposal Type
Mitigating and managing waste generated from production is a key objective for TPI. Our sites manage the waste generated according to local regulations. Our waste data is collected monthly using invoices collected from disposal facilities and haulers. All waste data is verified by on-site EHS supervisors and through annual audits conducted at our ISO14001 certified facilities. These processes allow TPI to understand the volume and cost of waste produced to ensure waste reduction remains a priority. We formed waste continuous improvement teams at each location, which worked to complete waste stream analysis and develop waste reduction projects. Many waste reduction projects were completed in 2021 that reduced the process waste sent to landfills through recycling, energy recovery (or waste-to-energy) incineration, or reuse. Energy recovery is a preferred method of waste management over treatment and disposal as it provides a source of energy generation and reduces carbon emissions due to the reduction of fossil fuel reliance1.
We met our process waste rate reduction goal (5% during the year) in 2021. The process waste that we focused on was a subset of our waste that is created as a byproduct of our manufacturing process such as excess material usage and consumable materials. The rate is defined as process waste divided by the total product weight. In 2021, we had 62,152 metric tons of waste, of which 9,298 metric tons was hazardous and 52854metric tons was nonhazardous waste. Hazardous waste increased year over year primarily due to the India facility being fully operational in 2021. Landfilled hazardous waste is disposed of through controlled confinement in a landfill that is lined, monitored, and in compliance with government regulations.
Raw material is the key cost driver of the products we manufacture. We are committed to doing our part in managing our material usage and waste production. We aim to use our materials as efficiently as we can while still meeting the expectations and requirements of our customers. Since the wind blades we build are based on our customers’ designs, the materials used to build them are generally determined by our customers. We currently track the materials used in our manufacturing processes through our product lifecycle management system and enterprise resource planning system. Two percent of our materials used in 2021 were from renewable resources, balsa wood, and one percent were from recycled sources, polyethylene terephthalate (PET).
1 EPA. (2020). “Energy Recovery from the Combustion of Municipal Solid Waste (MSW)”