Climate mitigation will have significant impacts on government spending necessary to finance large-scale deployment of Negative Emission Technologies (NETs). The required expenditure might consume up to a third of general government expenditure in advanced economies.

The Paris Agreement aims to limit global temperature increase to 2 °C above preindustrial levels and to balance GHG sources and sinks in the second half of this century. The technical feasibility of these targets has broadly been demonstrated by the 5th Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC). Recent publications, however, raise concerns about the broader political and economic feasibility of compatible emission trajectories, which typically rely on large-scale deployment of Negative Emission Technologies (NETs)—a type of pilot backstop technology that is often associated with enormous amounts of natural land loss, stranded assets by 2100, a potentially dangerous emission overshoot level and resulting fundamental ethical issues of intergenerational equity. Here, we argue that the financial viability of late-century NETs has thus far not been adequately addressed and show that NETs enter IPCC scenarios for the wrong (discounting), not for the right reason (hedging uncertainties).