Achieving Net-Zero Will Require a Mix of Nature and Technology

This blog was coauthored by Madeleine Hardy and Caspar Noach.

Even in the ideal net-zero 2050 scenario, we will need CO2 removal to live in such a world. As explained in our previous blog, When Net-Zero Really Means Just Zero, residual emissions are only expected to remain in a few sectors by 2050 and will need to be neutralized. This blog discusses the current and future markets for CO2 removals and how organizations with net-zero targets can future-proof their removal strategy.

Removal Options

CO2 removal is any process that clears CO2 from the atmosphere and sequesters it for a long period of time. This can range from natural solutions, such as afforestation/reforestation, to technological options, such as direct air capture with carbon storage (DACCS), bioenergy with CCS (BECCS), and less well-known options such as CO2 mineralization. The removal options that will be eligible for net-zero targets under partnerships such as the Science Based Targets initiative are still up in the air, but they will soon be defined in the initiative’s net-zero criteria.

CO2 Removal Options

(Source: Guidehouse, ClimateWorks)

State of the CO2 Removal Market

In today’s carbon removal market, afforestation/reforestation projects are the most prevalent. While this is the most mature market, it is also one of the most contentious. These nature-based solutions can play an important and positive role for the global climate but are associated with several risks. Notable concerns include CO2 storage (im)permanence, the accuracy of complex greenhouse gas accounting (since nature is more complex than theory), and biodiversity. Strict, harmonized standards and diligent monitoring to help projects deliver positive impacts in the long term are important.

There is the unavoidable fact that this type of CO2 removal requires land. While it is a seemingly limitless resource, land already faces competing uses: residences, food, materials, biofuels, industry, and livestock—among many others. Some quick math shows that there is simply not enough land for all organizations with a net-zero target to plant their way to net neutrality. Let’s assume that the world’s largest emitters use afforestation/reforestation to neutralize 15% of their emissions in 2050. This would require additional forestland equivalent to 37% of the area of the European continent. 

Illustration of Forest Area Needed to Neutralize 15% of the World’s Largest Emitters’ Emissions

(Source: Guidehouse)

While reforestation and afforestation cannot be the only carbon removal options used, technology-based solutions still face barriers. DACCS, for example, is still a young and relatively expensive technology compared to other removals options, with current costs ranging between $250/tCO2-$600/tCO2 while reforestation projects usually cost less than $50/tCO2. Additionally, the ongoing pilot projects aim to deliver a capacity of 4 ktCO2/yr-100 ktCO2/yr, not nearly enough to satiate the gigaton-scale removal demands of net-zero 2050 plans. BECCS, which is expected to play a large role in 1.5°C scenarios, could have land-related limitations.

Future-Proof Portfolios

There is no single answer, and organizations will need to look beyond current solutions and diversify their CO2 removal portfolios. Microsoft is a good example of this—they will initially focus on the available nature-based solutions, but plan to broaden their portfolio to include technology-based ones such as DACCS and BECCS between now and 2050. Microsoft will assess CO2 removal options with four criteria:

• Scalability

• Affordability

• Commercial availability

• Verifiability

The bottom line: Planting new trees is not going to cut it. To facilitate the scalability, affordability, availability, and verifiability of other CO2 removal options by 2050, organizations must send a market signal to help accelerate immature removal options and further explore the less-understood options with potential.