Carbon: Know your enemy

The era of carbon awareness has arrived. Everyone wants to be carbon neutral,
or even better, carbon negative. People are flying less, minimising their waste production, recycling, planting trees or offsetting emissions. Businesses are focusing on scopes 1 to 3, hoping to be able to reach their ambitious goals for 2025, 2030 or even 2050. Carbon dioxide - CO2 - is a transparent gas, elusive in its state and in our ability to grasp it. To make it more tangible, Efrat Friedland, founder of materialscout, proposes to take us on a carbon journey.

Carbon dioxide (CO2) is produced by burning carbon and organic compounds, by fermentation and by respiration. It can be naturally found in the air and is absorbed by plants during the process of photosynthesis. As one of the greenhouse gases, a notorious group that also includes fluorinated gases, methane (CH4) and nitrous oxide (N2O), it was cho- sen to be their representative. As a result, the environmental burden is calculated as Xkg equivalent to kilograms of CO2 - in short, the carbon footprint.

Calculating a carbon footprint is no easy task. Companies use the Life Cycle Assessment (LCA) tool to quantify the environmental impact of their operation. This allows the impacts of a product, process or activity throughout the entire life cycle to be calculated; from the extraction of raw materials through to processing, transport, use and end of life.

LCAs are conducted by experts and tend to be time and cost intensive. This has prompted several start-ups to create easy-to-use, online tools that allow a more simplified calculation of the carbon footprint, including a few that are free of charge. Focusing on household emissions in the US market is the CoolClimate Calculator that includes the four main categories of household consumption. Its UK equivalent, the WWF Footprint Calculator, is considered the most comprehensive and user friendly, offering multiple choice questions. However, it is limited to UK residents. The Business Carbon Calculator is a global calculator, offering SMEs a free online tool to calculate their operational impact. Perhaps the most revolutionary is the calculator developed by Swedish fin- tech company Doconomy. Their 2030 calculator can be used by any product, brand or manufacturer to quickly calculate the carbon footprint of their products. They offer additional corporate and lifestyle calculators, and even a carbon-offsetting credit card that monitors purchases according to their carbon emissions and puts a cap on spending based on the user’s impact on the climate.

Carbon capture

One way to reduce our carbon footprint is by preventing emissions of this gas into the atmosphere in the first place. Another approach is to capture it – to pull it directly from the atmosphere in a process known as carbon sequestering - and then to repurpose it.

AIR-INK is a material that was born in 2013 during an experiment at the MIT Media Lab, which later become the company Graviky Labs. This company has developed technology to capture pollution - in the form of emissions - after which they separate the carbon from the emissions, mix this with different oils and solutions to formulate useable pigments and ink with advanced material properties. They produce markers filled with this “carbon ink” and ink for screen printing applications, they collaborate with fashion brands that use AIR- INK to print on textiles (Pangaia) and with Doconomy to produce the carbon-offsetting credit card.

Newlight Technologies is another established player in the carbon-sequestration field.

That company has developed, patented and commercialised a technology that converts carbon into high-performance materials. The carbon is first captured, diluted with air and inserted into the polymerisation system where microorganisms turn it into a biomaterial, PHB, that can be extruded, blow moulded or injection moulded to be applied in various products.

It was also only a matter of time before the fashion industry, estimated to be responsible for 8-10% of global carbon emissions, climbed on the bandwagon and a fibre or textile producer started developing products based on sequestered carbon. Fairbrics is a French start-up that captures CO2 from industrial sources and mixes this with a catalyst and solvent to generate chemicals that are used for polyester synthesis. These chemicals are polymerised to create polyester pellets which are then spun into yarn and finally into fabric. Using this technology, they can produce carbon-negative PET. The last example in this category is H&M. This global brand is currently experimenting with aprons that capture CO2. The staff of a Swedish restaurant wear these aprons, which are heated to 30-40°C at the end of the day and the CO2 released is later used to nourish plants. Apparently, one apron can absorb around a third of CO2 a tree absorbs per day! The Hong Kong Research Institute of Textile and Apparel (HKRITA) is behind this chemical process, using an amine-containing solution which is applied on cotton, fibre, yarn or fabric.

Locking it up

A third approach to dealing with CO2 emissions involves locking the CO2 up. It may come as a surprise to most people, but the CO2 stored in a dead tree on the floor of the forest, or a pile of wood waste or sawdust, gets re-released into the atmosphere during the process of decomposition or burning. To prevent this from happening, a few companies are exploring how, instead, this gas can be locked up. Made of Air was founded in Berlin by two architects who began their journey by designing carbon capturing tiles for external cladding. Additional capital and a larger team led to the development of proprietary materials using wood waste, turning it into biochar and producing injection mouldable pellets.

Pyreg, a company with a focus on technology and not on output materials, has developed carbonisation chambers to locally upcycle organic waste into valuable biochar, thereby “closing the loop”. And it’s not just wood that can be used: Pyreg can turn any agricultural waste, paper waste, polymers and even sewage sludge into this black gold. They have various business models, including providing CO2 - sink certificates for companies. Another example, also in Germany, are the Carbonauten, who define themselves as a ‘minus CO2 factory.’ They offer carbonation modules that can turn any type of biomass into biochar. The output of the process depends on the quality of the input, and can be renewable energy, biofuel, biochar or all of the above.

The biochar can be used as fertiliser for plants and animals or as an additive in polymers. These are commercialised as Negative Emission Technology - NET - Materials, using biochar with various substrates for different applications.

Time to act

Carbon dioxide concentrations are rising mostly because of the fossil fuels that are being burnt for energy. These are coal and oil that contain carbon that plants pulled out of the atmosphere through photosynthesis over many millions of years. According to the American Meteorological Society, we are returning that carbon to the atmosphere in just a few hundred years. Even the global pandemic has failed to slow this process: the global average amount of carbon dioxide hit a new record high of 412.5 parts per million in 2020. Business as usual is no longer an option. The time to reduce, sequester and lock CO2 is now.