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Since the advent of sustainable textiles, public discourse has been dominated by CO2 emissions. One of the most important resources – water – has been neglected. Yet water is a finite resource. Only one percent of the world’s freshwater supplies are potable and are used by 7.5 million people, according to the mantra of SaltyCO. The British start-up has set out to establish an alternative to freshwater-intensive cotton cultivation: freshwater-free textile fibers!

Around 700 million people worldwide suffer from water scarcity (source: Global Water Institute). This contrasts with a clothing industry that requires 1,200 liters of water to produce a single cotton sock! This is enough to supply one person with drinking water for three years, according to SaltyCO CEO Julian Ellis-Brown in the video below. The main culprit behind the high water consumption is freshwater-intensive cotton farming. A side effect of this wasteful use of freshwater is the excessive irrigation of soils, which leads to desertification and salinization. This type of destruction affects one-third of the Earth’s landmass.

Salt-tolerant plants

Saltwater has often been overlooked in the production of textile fibers. Yet 97 percent of the world’s water resources consist of seawater. Ellis-Brown, a mechanical engineer and designer, wants to rethink the system and establish a new category in sustainable textile production: freshwater-free materials with supply chains that have a healing effect on nature. He found comrades-in-arms in fellow former students Antonia Jara Contreras, Finlay Duncan and Neloufar Taheri. The young researchers met as part of an innovation program at the Royal College of Art and Imperial College London.

Also of interest: Luxury fashion groups commit to making cotton farming resource-efficient

The four are focusing their research on plants that are salt-tolerant. This is because salt-tolerant plants (halophytes) can be irrigated with seawater, which could reduce dependence on freshwater-intensive cotton cultivation. In addition, salt-tolerant plants have a unique soil-cleansing function: they can extract and store salt from salinized soils. This means that the soils are freed from salt after the plants have been harvested.

An alternative to cotton cultivation

The start-up has already found a suitable salt-tolerant plant for the textile supply chain. Now they are researching regenerative cultivation techniques and textile products and are getting support from conservation groups and farmers in Scotland. There is no one-size-fits-all solution for sustainability. Instead, the researchers say, it is necessary to start from the respective condition of the soil to find a beneficial solution.

Saline agriculture

They cannot name the plant for copyright reasons. But in their cultivation technique, they follow the principles of saline agriculture, using sources other than freshwater to irrigate the plants. Seawater, brackish water or wastewater are alternatives that can counteract the damage caused by artificial irrigation in traditional agriculture. Artificial irrigation is one of the main reasons for salinized soils. This is because water always contains some salt, and when water evaporates, salts such as chlorides, sulfates and carbonates of sodium, calcium and magnesium, as well as nitrates remain in the upper soil layers. The high concentration of salts in soils disrupts the osmotic processes by which plants take up water and nutrients. In addition, the resulting soil compaction makes it difficult for roots to grow.

Healing factor of salt marshes

Salt marshes are among the areas with the highest healing factor. The plants that grow in them sequester 50 times the amount of CO2 as the same area of rainforest. In addition, salt marsh-based agriculture restores water sources and provides flood control. Growing salt-tolerant crops in these environments allows previously unused land to be redeveloped and salt-affected areas affected by rising sea levels to be restored. Interest in the innovation is high: the start-up is already receiving inquiries from communities around the world that want to use the regenerative cultivation technique to build a local industry as an alternative to growing cotton.

Freshwater-free textiles

SaltyCO’s laboratory, warehouse and production facility are located in Scotland. This is where the plants arrive after harvesting and where the plant fibers are mechanically extracted. The young researchers have also rethought this process and applied for a patent. Together with research partners from the fields of biological fiber coatings and fiber architectures, they have already developed three freshwater-free textile products: a type of felt, a fabric and an engineered filling material. All innovations are compatible with current supply chains. The felt lends itself to a vegan leather alternative, and the fabric is similar in texture to cotton and linen. Most advanced is the development of technical fiberfill, the kind that is familiar from anoraks and sleeping bags.

Vegan and biodegradable

The fiber goes by the name BioPuff, is made of pure cellulose and is an ecological alternative to animal- and petroleum-based products. Compared to petroleum-based synthetic fiber padding, 70 percent of the petroleum and up to 25 liters of fresh drinking water can be saved per jacket in production. In addition, the new type of fiber filling is cruelty-free: compared to common down fillings, the feathers of up to 30 geese can be saved per jacket.

BioPuff has a natural cluster structure that traps and stores heat in small air chambers, a natural property further optimized by green chemistry. As such, the fiber is easily composted and biodegrades at the end of its life.


The technical fiber filling is similar in its cluster structure to down, one of the warmest insulating materials for clothing. It is lightweight, soft, warm and naturally water repellent. A natural wax layer prevents the material from soaking up water in wet weather. The fill-to-weight ratio is comparable to the 600 cuin fill power or bulk of goose down. The fill power is a quality characteristic and describes the ability of the down to regain its original volume after compression through storage or use. The higher the measurement, the more insulating and warming the down product. For outdoor clothing, the minimum measurement is 550 cuin. These values make the goal of putting an end to the cruel live plucking of geese more attainable.

The young researchers have already gained a fan in British designer Stella McCartney. She was one of the first fashion designers to integrate vegan and sustainable concepts into her collection. Now she has also shown interest in using the technical filling material. But the first jackets and coats were created in a collaboration with Italian online fashion retailer The capsule collection was launched on December 2, 2021. A photo of the campaign can be found here.

Also interesting: Truly sustainable cotton that is water repellent, fluorescent and super magnetic