It is clear that reducing new greenhouse gas (GHG) emissions levels is critical to achieving global net-zero targets and capping global warming at 1.5°C. However, it is becoming increasingly clear that solutions must go beyond emissions reductions and begin to incorporate carbon dioxide removal (CDR) if we truly want to achieve these goals.
Without CDR, legacy emissions—those which have historically already been released into the air—will prove difficult to offset by 2050. In fact, the World Resources Institute (WRI) reports that we may need to remove “up to 10 billion metric tons of carbon dioxide per year by mid-century — that’s equivalent to the volume of 4,000,000 Olympic swimming pools.”
CDR is often divided into nature-based and technology-based removals. Nature-based removals include land management, afforestation and reforestation, while technology-based removals include enhanced rock weathering, carbon storage in biomass, carbon mineralization, and direct air capture (DAC).
A major benefit of technology-based CDR as opposed to nature-based solutions is the permanence and longevity offered by many CDR technologies. For example, carbon mineralization, the process of converting carbon dioxide into calcium carbonate for permanent storage in rock-like materials, has been proven to trap emissions out of the air and into these materials for thousands of years.
While nature-based CDR has seen widespread expansion, technology-based CDR has historically experienced a comparatively slow rate of adoption, and is only now catching up. This is largely due to the need for advanced R&D to cost-effectively scale these new technologies. Once brought to full industrial scale, the capacity of technological CDR has the potential to rapidly enable net-zero goals on a global scale.
Of 72 countries that have submitted a long term strategy (LTS) for climate change mitigation to the United Nations Framework Convention on Climate Change (UNFCCC), over 25 plan to incorporate technological CDR into their forward-looking climate portfolio. This number is bound to grow as CDR technologies mature and become inherently less risky to adopt on a nationwide basis.
While it is important to consider a diverse portfolio of CDR technologies in net-zero strategies, the WRI also emphasizes that, over time, technology-based CDR must begin to outpace that of nature-based CDR if we are going to achieve net zero emissions. One way to promote nascent tech-based CDR solutions is through procurement of materials that make use of CDR processes.
At CarbiCrete, CDR technology is applied to the production of concrete— the most-used manmade material in the world. Concrete’s chief ingredient, cement, is the source of nearly 8% of all annual GHG emissions worldwide. CarbiCrete’s proprietary technology uses carbon mineralization to cure a steel slag-based concrete, doing away with cement, which is responsible for nearly 95% of its associated emissions. Through avoiding new emissions and trapping historical ones, the CarbiCrete process exemplifies the use of CDR for building a cleaner future.
