No abstract

The production of heavy industry commodities is responsible for 1/3 of annual global GHG emissions. The Paris Agreement goals of +1.5-2°C require global emissions reach net-zero and possibly negative somewhere between 2060 and 2080. Given the normal timetable for retirement or retrofit of industrial facilities (>=20 years) all new equipment must be net-zero or negative carbon by the early 2040s. In this article we demonstrate to policymakers and modellers that industrial decarbonization is technically possible and how it might be achieved. First, we synthesize sectoral lab-bench and near-commercial technology options for reducing emissions to net-zero within 1-2 investment cycles, pathways more or less appropriate given regional resources (i.e. access to biomass, renewable electricity, or geological storage of CO 2) and political circumstances. Second, we synthesize policy options, focussing on those that encourage a managed transition from today's industry to net-zero emissions with a minimum of stranded assets, unemployment and social trauma.

After nearly two decades of debate and fundamental disagreement, top-down and bottom-up energy-economy modelers, sometimes referred to as modeling 'tribes', began to engage in productive dialogue in the mid-1990s (IPCC 2001). From this methodological conversation have emerged modeling approaches that offer a hybrid of the two perspectives. Yet, while individual publications over the past decade have described efforts at hybrid modeling, there has not as yet been a systematic assessment of their prospects and challenges. To this end, several research teams that explore hybrid modeling held a workshop in Paris on April 20-21, 2005 to share and compare the strategies and techniques that each has applied to the development of hybrid modeling. This special issue provides the results of the workshop and of follow-up efforts between different researchers to exchange ideas. 1. THE oRiGinAL BoTToM-uP / ToP-DoWn DiviSion Policy-makers are interested in a better understanding of the effectiveness and cost of policies whose purpose is to shift energy systems toward more environmentally desirable technology paths. What technologies would serve this purpose, and how could or would the economy adapt in response to policy to