A new report shows how the United States can reduce greenhouse gas emissions by 80 percent by 2050, using existing or near-commercial technologies. The 80 percent reduction by 2050 (“80 by 50”) is a long-standing goal of the Obama administration, in line with the global commitment to limit global warming to less than 2 degrees Celsius. The new report, issued by the Deep Decarbonization Pathways Project (DDPP), comes on the heels of the historic climate agreement last week between the United States and China, in which the U.S. government reiterated the 80 by 50 goal.
“This US Deep Decarbonization Pathways Report shows that an 80 percent reduction of emissions by 2050 is fully feasible, and indeed can be achieved with many alternative approaches. This reports shows how to do it,” said Jeffrey Sachs, director of the Earth Institute at Columbia University and the UN Sustainable Development Solutions Network. “I believe that the report provides a solid basis for negotiating a strong climate treaty in Paris in December 2015.”
Researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), Pacific Northwest National Laboratory (PNNL), and San Francisco-based consulting firm Energy and Environmental Economics, Inc. (E3) authored the report as part of the DDPP. The DDPP is led by the Sustainable Development Solutions Network and the French Institute for Sustainable Development and International Relations.
“This report shows it is feasible to dramatically cut greenhouse gas emissions in the U.S. by 2050 without requiring early retirement of infrastructure,” said Jim Williams, chief scientist at E3 and lead author on the report. “Moreover, the economic assumptions in this analysis were intentionally conservative, and the results demonstrate that even then deep decarbonization is not prohibitively expensive.”
The study analyzed four different low-carbon scenarios covering different energy saving measures, fuel switching, and four types of decarbonized electricity: renewable energy, nuclear energy, fossil fuel with carbon capture and storage, and a mixed case. The scenarios achieved reductions of 83% below 2005 levels, and 80% below 1990 levels.
“All four scenarios we tested assumed economic growth,” said Margaret Torn, senior scientist and co-head of the Climate and Carbon Sciences Program at Berkeley Lab, faculty in the Energy and Resources Group at the University of California, Berkeley, and coauthor of the DDPP report. “All of our scenarios deliver the energy services that strong economic growth demands.”
The report finds that the net costs would be on the order of 1% of gross domestic product per year. But the report said that included a wide uncertainty range, from -0.2% to +1.8% of a forecast GDP of $40 trillion, due to uncertainty about consumption levels, technology costs and fossil fuel prices nearly 40 years into the future. The researchers assumed lifestyles similar to those today, and extrapolated technology costs based on present expectations.
“If you bet on America’s ability to develop and commercialize new technologies, then the net cost of transforming the energy system could be very low, even negative, when you take fuel savings into account,” said Williams. “And that is not counting the potential economic benefits of a low-carbon energy system for climate change and public health.”
The report suggests that a multifaceted technology approach is needed to meet the greenhouse gas reduction target. Buildings, transportation and industry need to increase energy efficiency. This includes building structures with smart materials and energy-efficient designs, and fueling vehicles with electricity generated from sources including wind, solar, or nuclear, as opposed to coal.
“One important conclusion is that investment opportunities in clean technologies will arise during the natural rollover and replacement of infrastructure,” said Williams. “The plan calls for non-disruptive, sustained infrastructure transitions that can deeply decarbonize the U.S. by 2050, and enhance its competitive position in the process.”
The U.S. DDPP Report is one of 15 DDPP country studies that are part of the global project. It aims to show practical pathways to deep decarbonization consistent with the globally agreed 2-degree Celsius upper limit on warming to reduce the likelihood of dangerous climate change.
