An important element in decarbonisation is negative emissions technologies (NETs). These are technologies for drawing greenhouse gases out of the air and permanently storing them. To limit global heating to 1.5°C, it is estimated that we will need to remove around 810 GtCO₂ between now and 2100 — equivalent to 15 years of 2017 greenhouse-gas emissions.²⁷ Most scenarios for achieving net-zero emissions, and for limiting global heating to 1.5°C or 2°C, include the future effect of NETs that are predicted to mature later this century.

Future Horizons:

×××

5-yearhorizon

Research innovation assists carbon capture and use technologies

Investment in new direct air capture (DAC) technologies reinvigorates academic research in the field. AI-based chemical innovations begin to find applications for repurposing captured carbon.

10-yearhorizon

NETs begin to scale

Testing of ocean liming and iron fertilisation gives indications of whether these projects have potential. Advances in DAC technology, combined with rising carbon pricing, spur further investment in research. The first large-scale BECCS (bioenergy with carbon capture and storage) project begins. Construction materials that include captured carbon become commonplace.

25-yearhorizon

Carbon capture becomes a widely used technology

DAC is implemented on a large scale. AI helps to find new uses for captured carbon. Long-term storage solutions are agreed and implemented.

Some NETs are natural climate solutions. Reforestation can be a NET, because trees take carbon dioxide from the air. Other natural climate solutions include restoring wetlands and kelp forests, which are also carbon sinks. Natural climate solutions could mop up at most 23.8 Gt GtCO₂ per year.²⁸

Other NETs are highly artificial. Enhanced weathering entails crushing minerals into powder, which reacts with CO₂ and water to form a new mineral that can be used or buried. Lime can be thrown into the ocean to react with dissolved CO₂ to produce calcium carbonate that sinks to the seabed.

Direct air capture (DAC) uses machines that contain chemical “sponges” that draw CO₂ out of the air. This CO₂ can be sequestrated in underground repositories such as aquifers or depleted oil and gas reservoirs. Alternatively, it can be converted into fuels, fertilisers or construction materials — though this does not necessarily reduce emissions.

All these technologies face problems of scale, cost and geopolitics.

Negative emissions technologies - Anticipation Scores

The Anticipation Potential of a research field is determined by the capacity for impactful action in the present, considering possible future transformative breakthroughs in a field over a 25-year outlook. A field with a high Anticipation Potential, therefore, combines the potential range of future transformative possibilities engendered by a research area with a wide field of opportunities for action in the present. We asked researchers in the field to anticipate:

The uncertainty related to future science breakthroughs in the field
The transformative effect anticipated breakthroughs may have on research and society
The scope for action in the present in relation to anticipated breakthroughs.

This chart represents a summary of their responses to each of these elements, which when combined, provide the Anticipation Potential for the topic. See methodology for more information.