What Will It Take to Avert Collapse?

A lot of people are asking the question these days—including serious folks who work full-time on climate and energy policy. How can the world’s nations reduce greenhouse gas emissions fast enough to forestall climate catastrophe, without undermining either the global economy (which is still 85 percent dependent on fossil fuels) or the hopes of billions of people in poorer countries to raise their economic prospects through “development”—which historically has depended on increasing per capita energy usage?

The United Nations has passed this vexing question along to the global climate science community as a formal request to write a Special Report providing “feasible” pathways to limit global warming to 1.5 degrees Celsius while supporting economic growth and meeting the UN’s Sustainable Development Goals. The science community has responded by publishing papers featuring scenarios to fit those specifications. Until recently, most scenarios have relied on negative emissions technologies, including CCS (capturing carbon from fossil-fueled power plants, then sequestering it), or BECCS (growing biomass crops, burning them for power, then recapturing the carbon and storing it). Critics have savaged these plans as being too expensive and too environmentally risky.

A major new 13-page paper in Nature Energy, with 122 pages of supplementary materials, takes an entirely different approach. The goal of the authors, led by Arnolf Grubler, was to model a scenario that limits global warming to 1.5 °C while meeting economic goals withoutinvoking negative emission technologies—relying instead on energy demand reduction. We and our colleagues at Post Carbon Institute have for years promoted demand reduction as the primary viable pathway to averting catastrophic climate change. However, we assume that reducing energy usage dramatically would also result in economic contraction; indeed, we don’t see any way to maintain growth much longer as energy from fossil fuels declines—whether due to climate policy or fossil fuel depletion. In our view, one of the main jobs of policy makers these days should be to find ways to minimize the impacts of economic retrenchment.

The authors of the paper are more sanguine; they write:

[W]e show how an appropriate scaling down of the size of the global energy system creates the necessary space for a feasible supply-side decarbonization within a 1.5 °C emission budget without the need for negative emission technologies and with significant sustainable development co-benefits.

We decided to take a close look at this low energy demand scenario to see just how feasible it is. Its assumptions appear transparent and well documented in the Supplemental Materials. However, as we dug into those assumptions, it was clear that the authors envision a nearly complete revamping of technology, institutions, behaviors, and belief systems to achieve their goals, and this societal transformation would need to start immediately.

To read the complete article, click here.