A successful long-term strategy to mitigate climate change will require fundamentally different technologies than we employ today.  This is because any future stabilization of atmospheric CO2 concentrations—the underlying goal of the UNFCCC and a necessity to limit climate change consequences—requires almost zero net emissions.  Yet, the bulk of the world’s energy use in power and transportation comes from carbon-emitting fossil fuels.  In the power sector, nuclear energy provides an abundant, large-scale technological solution but seems unlikely to expand dramatically for other reasons.  In the transportation sector, there are no off-the-shelf, practical zero-emissions solutions.

Even before we reach a long-term zero-emissions outcome, there are a variety of near-term technologies that could help bridge the gap.  Hybrid and clean diesel vehicles, improved building technologies, combined heat and power applications—all promise lower energy use from conventional fossil sources.  Even though these technologies exist, they have not been widely deployed.

Given the need for both the development and the deployment of new technologies to address climate change, it is important to understand the R&D process, candidate technologies, and possible policy levers.