The US Department of Energy has thrown its support behind a biotechnology venture spearheaded by Protein Evolution, aiming to establish whether tired-out polyester garments can be reborn as brand-new fabric rather than ending their days in landfill.
Central to the initiative is a $3 million commitment to determine whether PET-digesting enzymes can be woven into a manufacturing pipeline capable of functioning at industrial volume whilst remaining commercially viable on price.
The department has selected Protein Evolution to lead efforts scaling up a biological method for transforming polyethylene terephthalate—better known as PET—textile scraps into raw chemical building blocks destined for fresh polyester.
Pilot-plant specialist Xytel and the National Laboratory of the Rockies (previously branded the National Renewable Energy Laboratory) are lending their expertise to the collaboration.
The scheme sits among 56 ventures sharing a combined $117 million pot from the DOE’s Office of Critical Minerals and Energy Innovation, with Protein Evolution’s slice pencilled in at $3 million—though this sum remains subject to change as negotiations continue.
Officials at the department have stated their goal is to develop a recycling technique capable of matching, cost-wise, the raw materials used in traditional polyester manufacturing.
Polyester accounted for 59% of worldwide fibre output during 2024, yet figures reveals that a striking 88% of that total is still derived from freshly extracted resources.
The bulk of recycled polyester on the market today is fashioned from plastic bottles, whilst scraps from discarded garments contribute under 1% of overall supply.
On a molecular level, enzymes serve to split PET into two components: terephthalic acid and ethylene glycol.
Once refined, these compounds can re-enter conventional polyester manufacturing streams. As per WWD’s reporting, this route yields material on par with virgin polyester, sidestepping the diminished quality typically associated with repeated rounds of mechanical recycling.
Complications abound, however: pre-worn textiles differ enormously from one another and frequently carry dyes or chemical treatments applied during finishing.
Compounding matters, polyester fibres exhibit high crystallinity, a trait that limits enzymes’ ability to penetrate them effectively. Should the fabric require pre-softening via supplementary heat or additional processing steps, much of the financial and ecological benefit risks evaporating.
Findings from a 2022 National Laboratory of the Rockies study revealed that scientists sifted through upwards of 250 million protein sequences whilst hunting for enzymes capable of breaking down crystalline PET. Laboratory-scale bioreactor trials showed conversion rates approaching 98%, transforming PET into terephthalic acid and ethylene glycol within a 48-hour window.
That same research indicated that sidestepping certain energy-heavy steps could trim energy consumption across the supply chain by 45%, alongside a 38% reduction in emissions warming the planet, when set against enzymatic approaches that first require material softening.
Scientists involved also projected that extracting terephthalic acid from cast-off clothing and carpet fibres might cost under roughly $0.45 per pound, a figure that could eventually translate into cost reductions benefiting both manufacturers and, ultimately, shoppers.
Nonetheless, these figures stem from separate research rather than Protein Evolution’s specific methodology, and the energy department has yet to disclose financial or performance targets attached to the newly announced funding.
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