COMMENT: Best foot forward – starting on the road to scaling carbon removals

Published 13:09 on January 26, 2023  /  Last updated at 11:04 on December 19, 2023  /  Contributed Content, Other Content, Voluntary

Understanding the scalability of different carbon removal methods is a crucial first step on this journey towards achieving the billions of tonnes of removals a year needed to meet international climate targets, write Ted Christie-Miller and Victoria Harvey of BeZero Carbon.

By Ted Christie-Miller and Victoria Harvey, BeZero Carbon

A herculean effort in technological innovation will be required to reach international climate targets of 10 billion tonnes of carbon removal a year by 2050. Understanding the scalability of different carbon removal methods will be central to this mission.

In practice, this means carbon removal methods such as Direct Air Capture (DAC) accelerating from practically a standing start to billions of tonnes of carbon removal every year in less than three decades. For comparison, solar took around half a century to reach its current level of diffusion and it still has a long way to go.

So, understandably, when it comes to carbon removal technologies, there is one word on everyone’s lips: scalability. How do we know which methods are scalable? And how can we understand what limits their scalability?

Answering these questions is not straightforward.

First, there is a level of uncertainty surrounding scaling, with many future known unknowns such as population growth or energy mix which will impact the scalability of a technology. For example, if the global population trebles in size over the next century, there will be very high demand on food production and in turn land. This scenario would mean that those land-intensive methods that use biomass would be highly constrained.

Secondly, there are many factors – eight to be precise – which need to be assessed to understand how scalable a carbon removal method is. These include: energy, land, policy, finance, resources, localised impacts, ancillary value chains and monitoring, reporting and verification (MRV) readiness.

But, now we at carbon ratings agency BeZero Carbon are aiming to help make this challenge a whole lot easier. Today, BeZero released the findings from its Carbon Removal Scalability Assessment. This first-of-its-kind assessment looks at five carbon removal methods which presently makeup the lion’s share of this nascent market: Biochar; Bio-energy with Carbon Capture and Storage (BECCS); Enhanced Weathering; DAC; and Ocean Alkalinity Enhancement. The assessment uses a qualitative approach to assess how scalable each method is, on a relative basis, through the prism of each Universal Factor.

What does the Scalability Assessment tell us?

For starters, DAC and BECCS, two zeitgeists of the carbon removal world, both experience some significant barriers to scaling. DAC is energy and resource intensive and constrained by high costs. BECCS, on the other hand, has challenges around land use, localised impacts and resource requirements.

Biochar, a carbon removal method where biomass is transformed into a state where it cannot decay, has consistently lower barriers to scaling on a number of factors such as: energy, finance, ancillary value chains and MRV readiness. Enhanced Weathering, a method with similar climate and social benefits to Biochar but with less market maturity, faces challenges around policy, MRV readiness and land use.

Ocean Alkalinity Enhancement, a method which uses ground rocks to enhance the alkalinity of
the ocean, has a number of large barriers to scaling, due to significant policy barriers and lack of
consensus around MRV readiness which is inhibiting its route to market.

This Scalability Assessment can be used to identify market opportunities and inform policymakers. If a technology has a very significant barrier to scaling under a specific variable there is a commercial opportunity to be grasped by delivering on this gap. Equally, if there are very low barriers to scaling in an area which an investor or stakeholder values most, the Scalability Assessment will illuminate this. In the same vein this first-of-its-kind assessment will allow policymakers to understand key barriers and design policy levers to support carbon removal to scale.

All engineered carbon removal methods face a steep and long trek to reach the summit of a
billion tonne scale market. The time is tight to achieve this ambitious goal, with just 27 years
until our 2050 climate targets. Understanding the scalability of different carbon removal methods
is a crucial first step in this journey.

By Ted Christie-Miller is Head of Carbon Removal and Victoria Harvey is Research Associate, both at BeZero Carbon, BeZero Carbon, a global carbon ratings agency.

Any opinions published in this commentary reflect the views of the author(s) and not of Carbon Pulse.