A new study by researchers at the MIT Center for Sustainability Science and Strategy reveals that diversifying carbon dioxide removal strategies offers a dual economic and environmental advantage, providing the best return on investment while minimizing land, energy consumption, and negative impacts.
A new study by researchers at the MIT Center for Sustainability Science and Strategy has found that diversifying carbon dioxide removal (CDR) options delivers the best return on investment. The study, which appears in the journal Environmental Research Letters, evaluated portfolios of five CDR options to assess their capability to meet the 1.5°C goal and their potential impacts on land, energy, and policy costs.
Carbon sequestration is a process that involves capturing and storing atmospheric carbon dioxide (CO2).
This can be achieved through various methods, including afforestation/reforestation, soil carbon sequestration, ocean fertilization, and carbon capture and storage (CCS) technologies.
According to the IPCC, CCS has the potential to reduce CO2 emissions by up to 90% in industrial processes.
In 2020, global CO2 emissions reached a record high of 33 billion metric tons.
Effective carbon sequestration strategies are essential for mitigating climate change and achieving net-zero emissions.
Diversification is Key
The researchers found that diversifying CDR portfolios is the most cost-effective net-zero strategy for achieving global net-zero emissions. This approach minimizes overall cropland and energy consumption, and negative impacts such as increased food insecurity and decreased energy supplies. By diversifying across multiple CDR options, the highest CDR deployment of around 31.5 gigatons of CO2 per year is achieved in 2100.
CDR Options Compared
The study compared five CDR options: bioenergy with carbon capture and storage (BECCS), afforestation/reforestation, ‘direct air carbon capture and storage’ (DACCS), biochar, and enhanced weathering. The researchers found that BECCS and biochar are the most cost-competitive in removing CO2 from the atmosphere, followed by enhanced weathering. DACCS was found to be uncompetitive due to high capital and energy requirements.
Regional Considerations
The study also highlights the importance of regional considerations when designing a CDR portfolio. The ideal CDR portfolio for a particular region will depend on local technological, economic, and geophysical conditions. For example, afforestation and reforestation would be of great benefit in places like Brazil, ‘Latin America’ , and Africa.
Timing is Everything
The researchers warn that delaying large-scale deployment of CDR portfolios could be very costly, leading to considerably higher carbon prices across the globe. They recommend near-term implementation of policy and financial incentives to help fast-track those efforts.
In conclusion, diversifying CDR options delivers the best return on investment and is essential for achieving global net-zero emissions. By considering regional conditions and implementing policies that support CDR deployment, we can mitigate climate change while promoting economic growth and environmental sustainability.
