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Carbon-negative biochar alternatives to fossil-based plastics are emerging as a practical, cost-effective, and workable solution to excess carbon dioxide in the air and seas.
Can Carbon-Negative Materials Help to Save the Planet?
The climate crisis that currently threatens our planet, its ecosystems, and populations, is becoming increasingly acute. Scientists warn that simply reducing energy consumption so that less carbon dioxide is emitted through the burning of fossil fuels will not be enough to prevent a climate emergency in this century. Carbon-negative materials could hold a part of the answer, as they actively reduce the amount of carbon in the atmosphere.
Dramatic rises in atmospheric (and hydrospheric) carbon levels since the start of the Industrial Revolution in the 18th century are in part due to exponential economic growth worldwide in the 20th century: economic growth required a constant stream of new materials for manufacturing, construction, and industry. These new materials are often the result of excessive carbon emissions through fossil fuel burning for energy, or their conversion into chemically unstable plastics.
Carbon-negative biochar alternatives to these materials are emerging as a practical and cost-effective solution. Made of Air, based in Berlin, Germany, is at the forefront of a carbon-negative materials revolution. The company’s thermoplastic biochar composite material is carbon-negative and leads to a net reduction of carbon in the atmosphere.
Like similar composite biochar materials (biochar clay and biochar plaster, for example) Made of Air’s carbon-negative thermoplastics can be used in construction and other industries today, enabling developers and planners to create new carbon sinks as a product of economic growth.
Video Credit: Made of Air GmbH/YouTube.com
Carbon-Negative Biochar: Learning from Nature
Carbon is the main ingredient for organic life on Earth. It makes up 45% of all plant matter and 60% of organic matter in soil. Carbon dioxide is released into the atmosphere through several natural and human-centered or industrial processes – carbon is naturally expected to cycle through the atmosphere, animal and plant life on Earth, and back into the atmosphere, or into waterways and eventually into the ocean.
Since the Industrial Revolution, this has increased dramatically due to reliance on burning fossil fuels such as oil, gas, and coal for energy. When these fuels burn, the carbon stored in them is chemically bonded to oxygen fueling the fire, and carbon dioxide is released into the atmosphere.
In the natural carbon cycle, trees and other plants (including algae and other aquatic flora) collect this carbon out of the air as part of the photosynthesis process. Some of this will be brought down further into the soil or deep sea. Earth and sea, in this manner, are referred to as carbon sinks – large areas that can store large amounts of carbon stably. However, the oceans are becoming too full of carbon, forest areas are decreasing, and atmospheric carbon levels continue to rise: the natural carbon cycle cannot sequester carbon fast enough to prevent environmental tragedy.
Fossil fuels have developed over millions of years from biomass buried below Earth’s surface. The effect of pressure on this material over time concentrates and stabilizes the carbon in it, which is what makes these materials such valuable fuels. Carbon-negative biochar alternatives are materials that have been created by watching and following the example of the natural carbon cycle.
In biochar production, trees and vegetation carry out the chemical work of removing carbon from the atmosphere through the photosynthesis process. Waste biomass from this vegetation is collected and processed using pyrolysis. In pyrolysis, biomass is treated in an oxygen-deprived, high-temperature, high-pressure vessel which mimics the millions of years of pressure that creates fossil fuels. The resulting product is a kind of charcoal, referred to as biochar.
How is Biochar Carbon Negative?
Biochar is carbon negative because it removes (through photosynthesis) and then sequesters (or stabilizes for storage) the carbon in the atmosphere, rather than emitting carbon. If it is not burned, biochar acts as a carbon sink just like the oceans and soil – carbon is sequestered and stabilized so that it will not be naturally emitted to the atmosphere.
There are some biochar critics who argue that it is not infinitely stable and will eventually return sequestered carbon to the atmosphere. However, studies have shown this process will take thousands of years and the current climate emergency requires immediate and cost-effective measures, including biochar production, to take carbon out of the atmosphere.
Biochar has also been criticized in the past due to the high energy costs it requires to produce. When biochar was first developed, the energy cost of producing it meant that the positive effects of carbon biosequestration could be reduced or even nullified by the negative effects of energy consumption (burning more fossil fuels).
The level of carbon stability achieved in biochar, and the energy required to produce it, are the key determiners of net carbon storage gain. If biochar is stable enough to maintain a mean residence time for the carbon (the time it would take for the material to decompose and release sequestered carbon) of around 2,000 years, and energy requirements to produce it are not excessive, then biochar is carbon-negative.
The latest generation of carbon-negative materials is produced with these considerations in mind. Made of Air and other companies producing biochar materials can ensure a so-called “energy-positive” production. Capturing emitted energy from the pyrolysis enables biochar producers to create more usable energy than they consume in the process of creating biochar.
Carbon-Negative Thermoplastics: Made of Air
Biochar has been applied as a soil enhancer, water filter and agricultural filler, but it is increasingly being applied in industries such as construction and fashion to replace plastics. Carbon-negative thermoplastics can contain up to 85% carbon sequestered from the atmosphere.
Made of Air is partnering with fashion retailers and car dealerships alike to show the world how carbon-negative biochar alternatives can help us to avoid an environmental disaster.
References and Further Reading
“Made of Air: Carbon Negative Materials.” Made of Air. [Online] https://www.madeofair.com/.
Cheriyadath, Susha (2020). “What is Pyrolysis?” AZO Cleantech. [Online] https://www.azocleantech.com/article.aspx?ArticleID=336.
Glaser, Bruno, Mike Parr, Christelle Braun and Goodspeed Kopolo (2009). “Biochar is Carbon Negative.” Nature Geosci. [Online] https://doi.org/10.1038/ngeo395.
Pilkington, Ben (2020). “Carbo Culture Biochar: Stable CO2 Removal Technology.” AZO Cleantech. [Online] https://www.azocleantech.com/article.aspx?ArticleID=1157.
Zhang, Qingfa, Hongzhen Cai, Keyan Yang and Weiming Yi (2017). “Effect of biochar on mechanical and flame retardant properties of wood – Plastic composites.” Results in Physics. [Online] https://doi.org/10.1016/j.rinp.2017.04.025.
Pudełko, A., P. Postawa, T. Stachowiak and K. Malińska D.Dróżdża (2021). “Waste Derived Biochar as an Alternative Filler in Biocomposites: Mechanical, Thermal and Morphological Properties of Biochar Added Biocomposites.” Journal of Cleaner Production. [Online] https://doi.org/10.1016/j.jclepro.2020.123850.