April 16, 2007
12:00 Noon - 2:00 pm
Dirksen Senate Office Building, Room 106
What is the scale of effort that is likely required to address the energy challenges posed by climate change? Have we, as a society, been successful in the past in organizing grand-scale programs to address critical issues of enormous scale? What are the suite of technologies and lifestyle changes that are likely to be essential components of an energy conversion program that effectively addresses the most serious threats and consequences of climate change? The grand challenges posed by unchecked greenhouse gas emissions will, no doubt, take considerable time and effort to deal with. What are likely to be some of the most effective strategies that can be deployed in the near- and mid-term? How critical is energy conservation in such a plan? Is it reasonable to assume that technological advances alone, in the absence of fundamental changes in our lifestyles and perspectives, are sufficient to tackle the problem at hand?
Dr. Anthony Socci, Senior Science Fellow, American Meteorological Society
Dr. Marty Hoffert, Professor Emeritus of Physics, New York University, New York, NY
PowerPoint HTML Version
Dr. Ken Caldeira, Department of Global Ecology, Carnegie Institution, and Professor (by courtesy) in the Stanford University Department of Geological and Environmental Sciences, Stanford, CA
PowerPoint HTML Version
Dr. Joseph Romm, Executive Director of the Center for Energy and Climate Solutions, former Acting Assistant Secretary, Office of Energy Efficiency and Renewable Energy, and former Principal Deputy Assistant Secretary, U.S. Department of Energy, Washington, DC
PowerPoint HTML Version
Climate Change and the Future of Energy: The Scale of the Task and Our Capacity for Coming to Grips with Large Undertakings
Dr. Romm - Avoiding the potentially worst manifestations of climate change would seem to necessitate >60% reductions in greenhouse gas emissions by mid-century. Positive carbon cycle feedbacks, such as methane emissions from melting tundra, further constrain allowable emissions. The emissions constraint is so formidable that it is likely to become the overriding force behind all energy and environmental policy within a decade. For instance, since we face a tripling in vehicle numbers by 2050, making the average vehicle >6x less polluting would not only be feasibly and attainable, but an essential component of any effective response strategy. Efficiency is by far the most cost-effective strategy, but analyses suggest that we will also likely need to largely replace gasoline with low-carbon fuels by mid-century.
Hydrogen is the most challenging alternative fuel, with enormous fueling infrastructure challenges. Low-carbon biofuels require significant arable land and thus will be a serious option only if we can effectively avoid the drought and desertification projected in a business-as-usual world. The most promising alternative fuel vehicle is a hybrid that can be connected to the electric grid. These so-called plug-in hybrids will likely travel three to four times as far on a kilowatt-hour of zero-carbon electricity as hydrogen cars. Ideally plug-ins would also be a flexible fuel vehicle capable of running on a blend of biofuels and gasoline.
Dr. Hoffert - Effectively addressing the climate/energy problem will likely require radical approaches well beyond those presently being contemplated by many. Given globally large coal resources, revolutionary shifts in primary power away from fossil fuels might seem deferrable to the 22nd century and beyond. But unchecked global warming/greenhouse gas emissions, and the time lags of climate and energy systems, would seem to warrant a considered but relatively immediate course correction. The coming decades seem crucial to our success in dealing with this issue. Whatever its political and economic dimensions, global warming mitigation will require massive high-tech engineering projects comparable in scale, at least, to the WW II industrial mobilization; projects of a type the US has historically excelled at. For example, preventing greater than 2 ºC global warming will require 100-300% of today's primary power coming from some combination of carbon-neutral energy and "negawatts" of demand reduction by mid-century: A Herculean, but eminently doable job, as judged by our having successfully taken on several such tasks over the course of the 20th century.
Technological options that might work with massive R & D and prompt implementation of successes include (1) coal gasification combined cycle power plants producing electricity and fuel cell grade hydrogen with CO2 sequestered underground; (2) new generations of operationally safe, proliferation-resistant and waste-managed nuclear reactors burning fuel bred from U-238 and thorium, and eventually fusion; and (3) renewable energy, primarily solar and wind, with innovative transmission and storage technologies deployed at the global scale, including space-based solar energy. Market mechanisms for technologies close to or "on the shelf" are important but unlikely by themselves to solve the objective problem; I will argue that only radical and technologically innovative Apollo Program-style R & D funded by governments, ideally led by the US, can provide the carbon-neutral energy needed to sustain high-tech civilization over time.
Dr. Caldeira - Most people share the twin goals of (1) economic growth and development (especially for the poorest people of the world) and (2) protection and restoration of our natural environment. However, the scale of sustained effort required to achieve these twin goals often goes unrecognized. The major infrastructure that we build today, including roads and electrical power plants, are likely to still be in use 50 years from now. Thus, we are already building the energy infrastructure for the second half of this century. Therefore, solving the climate problem of the second half of this century requires that we build the appropriate energy infrastructure in the first half of this century. If we are to solve the climate problem, the developing world must develop around energy technologies that do not emit carbon dioxide to the atmosphere.
If global GDP grows at 3% per year and the economic efficiency of energy use improves at a rate of 1 % per year, then energy demand might be expected to increase at about 2% per year. At this growth rate, energy demand doubles about every 35 years. With no fundamental change in our energy system or our use of energy, carbon dioxide emissions might also be expected to double every 35 years, with emissions roughly six times today's emissions by century's end. This would seem to be a virtually certain recipe for severe climate-induced damage on a grand scale.
A survey of available technologies that can likely meet the huge demand for affordable energy expected later this century suggests that there are only four options that might be environmentally acceptable: wind, solar, nuclear, and fossil-fuels with carbon capture and storage. Other options, such as biomass, may play a niche role but face barriers to scale-up that are likely to be insurmountable. Even these four options face major barriers, including those associated with intermittency, cost, safety, and regulatory compliance. Therefore, solving the climate problem involves not only the formidable political challenge to create economic incentives to apply technologies already at hand, but also requires a major long-term energy technology research and development effort aimed at creating energy systems that are both affordable and environmentally benign.
Dr. Joseph Romm is the Executive Director of the Center for Energy and Climate Solutions and a Senior Fellow at the Center for American Progress, where he oversees the blog ClimateProgress.org. He is author of Hell and High Water: Global Warming—The Solution and The Politics (William Morrow, 2007). Dr. Romm served as Acting Assistant Secretary at the U.S. Department of Energy's billion-dollar Office of the Energy Efficiency and Renewable Energy during 1997 and Principal Deputy Assistant Secretary from 1995 though 1998. Dr. Romm also helped lead the previous Administration's climate technology policy formulation, and he initiated, supervised, and publicized a comprehensive technical analysis by five national laboratories of how energy technologies can reduce greenhouse gas emissions at low-cost: Scenarios of U.S. Carbon Reductions.
Dr. Romm holds a Ph.D. in physics from M.I.T. . Much of his thesis work on physical oceanography was conducted at the Scripps Institution of Oceanography with Dr. Walter Munk. He has authored several dozen articles and six books, including The Hype About Hydrogen: Fact and Fiction in the Race to Save the Climate, named one of the best science and technology books of 2004 by Library Journal.
Dr. Martin I. Hoffert is Professor Emeritus of physics and former Chair of the Department of Applied Science at New York University. His academic background includes a B.S. (1960) in aeronautical engineering from the University of Michigan, Ann Arbor; M.S. (1964) and Ph.D. (1967) from the Polytechnic Institute of Brooklyn (now the Polytechnic Institute of New York) in astronautics; and a Master of Arts in liberal studies (1969) from the New School for Social Research where he did graduate work in sociology and economics. Dr. Hoffert has also been on the research staff of the Curtiss-Wright Corporation, General Applied Science Laboratories, Advanced Technology Laboratories, Riverside Research Institute, and the National Academy of Sciences, and was Senior Resident Research Associate at the NASA/Goddard Institute for Space Studies.
Dr. Hoffert has over 70 peer-reviewed publications in the areas of fluid mechanics, plasma physics, atmospheric science, oceanography, planetary atmospheres, environmental science, solar and wind energy conversion, and space solar power. His work in geophysics was aimed at development of theoretical models of atmospheres and oceans to address environmental issues, including the ocean/climate model first employed by the UN Intergovernmental Panel on Climate Change (IPCC) to assess global warming from different scenarios of fossil fuel use. His early model of the evolving CO2 greenhouse in Mars's atmosphere is also of interest today - providing both an explanation of Mars's riverbed-like channels formed in the distant past and a motivation for terraforming its atmosphere for human habitability in the future. His research in alternate energy conversion includes wind tunnel and full-scale experiments on innovative wind turbines, photovoltaic generation of hydrogen, and wireless power transmission (WPT) applied to solar power satellites. Dr. Hoffert's present efforts focus on energy technologies that could stabilize climate change from the fossil fuel greenhouse - including (but not limited to) space solar power. He is a member of the American Geophysical Union (AGU), the American Institute of Aeronautics and Astronautics (AIAA), and a Fellow of the American Association for the Advancement of Science (AAAS).
Dr. Ken Caldeira works on a broad array of issues associated with the consequences of carbon dioxide emissions and evaluating various options to reduce those emissions. He has been involved in several studies assessing the scale of effort that would be required to reduce the risk of severe damage from climate change. Recent publications have addressed topics as diverse as the potential to harvest renewable energy from high altitude winds, the effectiveness of planting forests as an approach to mitigating climate change, and the possibility of offsetting some of the effects of increasing greenhouse gas concentrations by deflecting some sunlight before it reaches Earth's surface. His 2003 paper in Nature magazine first introduced the term "ocean acidification" and helped bring attention to this important issue.
Dr. Caldeira was one of two technical advisors accompanying the US Government delegation in climate change negotiations leading up to the 2005 G8 summit in Gleneagles, Scotland. He was a coordinating lead author on the 2005 Intergovernmental Panel on Climate Change report on carbon capture and storage. He is a staff scientist with the Carnegie Institution Department of Global Ecology on the Stanford campus and also holds the position of Professor (by courtesy) in the Stanford University Department of Geological and Environmental Sciences. He received his PhD and MS in Atmospheric Sciences from New York University and his BA in Philosophy from Rutgers College.
back to top