Effectiveness and efficiency of climate change mitigation in a technologically uncertain World

Following a multi-scenario framework based on the technology assumptions proposed by the 27th Energy Modeling Forum (EMF-27), our analysis focuses on analyzing the impacts of key technology assumptions on climate policies, including the interdependencies of different technological options. Each scenario may be considered as either a possible state of nature upon which one has no influence, each scenario thus dictating the availability (or non availability) of some subset of the technology groups, or as an opportunity for society, by its own actions and policies, to influence the availability of said technology group. The main insights obtained from the assessment show the prominent role of bioenergy as a means to abate greenhouse gas emissions, irrespective of other technological developments, while the role of the other technologies (wind and solar, carbon capture and sequestration, nuclear) are more dependent of one another. It appears that CCS may play a sort of “backstop” role: it compensates for a lower contribution of solar and wind, or of nuclear. This means that an increased social acceptability of one (or all) of these three sets of technology should be at the heart of future climate policies. The costs caused by the adaptation of electricity networks to accommodate a high fraction of intermittent sources would deserve more attention in future research.