Aug-2024

Transforming carbon and paving the way for a circular economy

Carbon capture and utilisation could enable a new circular carbon economy where carbon is reused to generate value rather than wasted.

Freya Burton and Kit McDonnell
LanzaTech

Article Summary

This summer is likely to see continued record-breaking heatwaves, reminding everyone that climate change is not a distant future threat but a pressing and immediate danger. Indisputably, the globe needs to aggressively stem both the flow (mitigate new emissions) and the stock (remove existing emissions) of anthropogenic carbon in the atmosphere to bend the carbon curve to a liveable level (IPCC, 2023). Until now, the only option for carbon disposal has been in the atmosphere; unfortunately, the amount of CO2 the planet can manage has now been exceeded. There is an urgent need for a new home for carbon waste.

Luckily, we know today, at scale, how to transform that excess atmospheric carbon into valuable products by employing carbon capture and utilisation (CCU). CCU is often categorised with other carbon management means, such as carbon capture and storage (CCS). However, to date, CCUS has largely been synonymous with just CCS. This needs to change because the world deserves the additional benefits and value generated by efficient CCU operations, which both utilise waste carbon and generate value.

Carbon is all around us
Most people do not realise how deep carbon’s roots run into their lives. Carbon is the building block of all organic compounds, making up the essence of life on Earth, including humans. It is in the threads of clothes, the materials that build homes, and the fuel that powers vehicles. Yet, carbon, particularly in its gaseous form as carbon dioxide (CO₂), is a significant contributor to the planet’s most pressing environmental issues.

CO₂, a potent greenhouse gas, has been accumulating in the atmosphere mainly from industrial processes and petrochemical refining. These industries form the backbone of global supply chains, creating a carbon economy that thrives on non-renewable resources extracted from beneath the Earth. This extractive approach has led to the release of gigatons of CO₂, contributing to global warming and its accompanying catastrophes.

Most people do not realise that many of the products they use daily are also made from virgin fossil carbon. It is a key ingredient in everything from clothes and cosmetics to household cleaners and medical supplies.

Even if we managed to capture and store enough CO2 to combat climate change, carbon-dependent global supply chains would still require the extraction of fossil carbon to make the things we need. That is why when talking about carbon storage as a decarbonisation tool, it is also important to talk about carbon utilisation, CCS’s lesser-known cousin.

The reality is that barring a complete overhaul of the global economy, humans will always need carbon in some form. The good news is that there is already enough carbon above ground to make the products humans use without extracting more. What about plant-based carbon? That will also have a role to play. However, the scale of carbon use today is such that relying solely on biomass could pose challenges related to land use, deforestation, competition with food production, and other potential environmental impacts. So, a diversified carbon portfolio that does not have a negative impact on the planet is needed.

Reimagining the carbon economy
To protect life on Earth, it is necessary to rethink this extractive carbon economy and transition toward a circular model. Instead of taking virgin fossil carbon from the ground, the gigatons of carbon already in the atmosphere can be captured and reused to create sustainable products. This is where CCU comes into play, representing a pivotal shift in how carbon emissions are handled.

Companies like LanzaTech are pioneering this effort with technologies designed to capture industrial waste carbon at its source, preventing it from entering the atmosphere. CCU has the potential to enable circular economies from aggregated waste streams such as waste biomass, municipal solid waste, industrial off-gases, and biogases (landfills and livestock CH4).

Carbon recycling technologies can transform above-ground carbon sources into sustainable fuel and chemical products. These technologies offer an industrial approach to both enable fuel and chemical manufacturing at its current scale and achieve sustainability targets. Gas fermentation – using carbon-fixing micro-organisms – is a fully commercial carbon recycling process technology that transforms waste carbon resources into sustainable fuels, chemicals, and polymers at a scale that can be truly impactful in mitigating the climate crisis. LanzaTech has successfully scaled up the gas fermentation process from the laboratory bench to full commercial scale, with several commercial plants in operation and additional facilities in the pipeline.

CCU technologies can transform carbon into more sustainable chemical building blocks, like ethanol, which can be used in everyday products that traditionally rely on virgin fossil carbon. This approach not only mitigates new CO₂ emissions but also attempts to utilise the carbon already in the atmosphere.

Gigatonne challenge
Consider the scale of the challenge: globally, each year, industries release more than 37 billion tonnes of CO₂ into the atmosphere. One billion tonnes is equivalent to 1 gigatonne, so in just the last five years, humanity has produced more than 185 gigatonnes of CO2.

Despite the potential of these technologies, they are only scratching the surface. Similarly scaled solutions are needed to tackle the gigatonne-scale challenge of carbon emissions. This effort requires collaboration across consumers, industries, and governments to foster systemic change.

To fully utilise CO2, an energy source is needed, and for a fully sustainable solution, sustainably sourced renewable energy is needed. Solar and wind will play a key part in providing renewable solutions for energy sectors and, when combined with carbon transformation technologies, they will help turn atmospheric CO2 and sunlight into the building blocks for daily lives.

Growing global consensus on cutting carbon emissions has led to government investments in renewable energy infrastructure, including countries with economies historically reliant on fossil fuels. For example, India, the Kingdom of Saudi Arabia (KSA), and Nigeria have all set ambitious targets to increase their renewable energy capacity by 2030. With myriad projects underway, these regions have the opportunity to accelerate reduction efforts by deploying carbon management technologies alongside renewables.

Some of these countries have complementary initiatives to support CCU; for example, the KSA’s Ministry of Energy developed three years ago the Circular Carbon Economy National Program to guide public and private sector collaborations to achieve the four Rs of carbon management: Reduce, Reuse, Recycle, and Remove (KSA MoE, 2022).
As more countries prioritise renewable energy infrastructure, leaders must move quickly to capitalise on the momentum. If nations primed for green investments use this moment to rethink entire systems, the transition to a more sustainable global economy could speed up significantly.