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Electricity scenarios


Reinventing Fire envisions a future electricity sector in which widespread energy efficiency adoption has flattened demand growth, demand response and energy storage technologies have enabled increased use of variable renewable generators, and environmental responsibility, fuel availability concerns, and competitive logic have increased distributed and grid-scale renewables to at least 80% of U.S. 2050 electricity generation. To assess the implications of this and other possible scenarios, RMI developed and analyzed four patterns of how electricity might be generated, delivered, and consumed in the next 40 years. For these four cases—Maintain, Migrate, Renew, and Transform—RMI evaluated their performance in five areas: technical feasibility, affordability, reliability, environmental responsibility, and public acceptability.

The Maintain case is a “business-as-usual” projection of the future U.S. electricity system. Based on the U.S. Energy Information Administration’s 2010 reference case, this system differs little from today’s in infrastructure, policy, and regulatory structure. Smart grid and demand response programs remain insignificant, and most utilities continue to have a financial disincentive to encourage customers to use electricity more efficiently. Overall demand is much higher than today—having grown at around 1% per year— and is met largely by increased gas- and coal-fired generation.

RMI’s second case, Migrate, imagines a future in which the anticipation of legislation to reduce greenhouse gas emissions drives a shift to coal plants equipped with carbon capture and sequestration (CCS) and to new nuclear plants. This scenario requires the construction of three new nuclear plants and nine CCS-equipped coal plants each year for the next 40 years, at a total present value cost of $1.4 trillion. Increased nuclear generation requires high-level waste storage about twice the size of the abandoned Yucca Mountain facility in Nevada. And CCS— a largely unproven technology— is implemented at full scale on every new coal plant, raising questions about the ambiguous management responsibility and long-term stability of sequestered carbon. With more nuclear and more coal with CCS, the electricity sector emits almost 75% less carbon in 2050 than in the Maintain case, but still shy of the IPCC reduction target of 80% below 2000 levels. In this scenario, carbon reduction goals also encourage limited adoption of efficient use and renewable energy. However, because this electricity system is centered around extremely capital-intensive, long lead-time plants, utilities remain incentivized to sell more power and discourage efficiency programs.

Renew explores a future U.S. electricity system in which renewables—mostly at utility scale— provide at least 80% of 2050 electricity. There is widespread adoption of energy efficiency and participation in demand response programs, valued for their ability to complement generation from variable renewable sources. The increased energy efficiency flattens electricity demand growth, probably leading many regulators and utilities to challenge the current business model with new value propositions.

In RMI’s Transform case, aggressive energy efficiency adoption flattens and then reverses demand growth. Renewables’ installed capacity grows substantially, including a large capacity of distributed resources such as rooftop solar, combined heat and power (CHP), fuel cells, and small-scale wind. The grid exploits renewables’ geographic and technological diversity to improve load-following and reduce system costs. Unlike Renew with its more centralized renewables, this scenario would site most generation resources at or near customers. With more distributed generation and deployment of smart grid technology, the grid could be clustered in interlinked “microgrids” that could stand alone when necessary and improve the grid’s resilience against power failures.


Metz, B., O.R. Davidson, R. Bosch, and L.A. Meyer. 2007. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, 2007. Cambridge: Cambridge University Press.

Peterson, Per. 2003. “Will the United States Need a Second Geologic Repository?” The Bridge, National Academy of Engineering 33 (3). link

U.S. Energy Information Administration. 2010. Annual Energy Outlook 2010: WIth Projections to 2035. Washington, D.C.: U.S. Department of Energy, April. link