The goal of net-zero emissions aligns with the Paris Agreement, requiring a combination of reducing emissions and using Carbon Dioxide Removal (CDR) techniques. However, skepticism exists due to CDR’s economic, political, and technological complexities, alongside concerns over the impacts of large-scale Negative Emission Technologies and Practices (NETPs).
To inform responsible NETP deployment, extensive research conducted by the NEGEM research team at Potsdam Institute for Climate Impact Research has evaluated the potential trade-offs, impacts, and limitations of various methods. Every assessed NETP (including reforestation, BECCS, biochar, DACCS, and others) comes with trade-offs in at least one impact area.
While all options have drawbacks, reforestation/forest management stands out with considerable benefits alongside climate impact, including alignment with nature restoration goals. However, reforestation potential relies on significant shifts in land use practices and dietary habits. Land- and calorie-neutral approaches to biochar offer CDR potential without competing with food production. On the other hand, large-scale, intensive biomass production for BECCS could exacerbate pressure on planetary boundaries.
NETPs with geological storage can effectively offset residual emissions, while those relying on natural solutions are better suited for restoring carbon sinks but less reliable for permanent, ongoing removal.
Key highlights
A carefully considered portfolio of NETPs tailored to different contexts is necessary, acknowledging their limitations and ensuring they uphold broader Earth system stability and Sustainable Development Goals (SDGs). Uncertainties around the sustainable potential of several NETPs exist, emphasizing the urgency of rapid decarbonization to minimize the need for potentially less sustainable CDR implementations.