Negative emission technologies, effective way to reduce atmospheric CO2; A review

In order to limit the increase in the global average temperature to 2 °C or below, the Paris Agreement proposed the reduction of CO2 emissions throughout this century. Negative emissions technologies (NETs), which remove carbon dioxide from atmosphere and sequester it, represent an interesting option in order to allow this goal to be met goal. The removal of 10 Gt.yr−1 of CO2 globally by mid-century and 20 Gt.yr−1 of CO2 globally by the end of century. Several land-based negative emissions technologies are ready for large-scale deployment at costs competitive with emissions mitigation strategies. In this contribution, we study two distinct NETs, indirect air capture and direct air capture as main methods. In particular, three different technologies, including BECCS, absorption and adsorption. Besides several advantages, present high operational cost and its scale-up should be tested to know the real effect on climate change mitigation. With current knowledge, no single process should be seen as a solution. Research efforts should be performed to evaluate and reduce NETs costs and limitations.