If changing the U.S. energy supply to be more secure and sustainable is like steering a massive ship, then the direction we set it on today won't be fully felt for 10 or 20 years.
The National Research Council, the operating arm of the National Academies of Sciences and Engineering, on Monday released a report called "America's Energy Future" that seeks to focus the country's discussion on energy and draw attention to the most promising technologies.
One of the messages from the report is that long-term problems require sustained strategies and a break from business as usual. Technology has a big role to play, but none of the academic and business experts who authored the study expects a single fix.
"One of the committee's conclusions is that there is no technological 'silver bullet' at present that could transform the U.S. energy system through a substantial new source of clean and reasonably priced domestic energy. Instead, the transformation will require a balanced portfolio of existing (though perhaps modified) technologies, multiple new energy technologies, and new energy-efficiency and energy-use patterns," wrote Harold T. Shapiro, the chair of the committee on America's Energy Future.
Although there isn't one solution, certain technologies deserve more research than others, both in electricity and in transportation. Successful development and deployment of them can reduce greenhouse gases substantially in both sectors in the next 30 years using a portfolio approach.
In the short term, the study's authors concluded that efficiency is the easiest and lowest-cost option for "moderating" national demand for energy in the next decade.
Adopting existing building-efficiency products alone could potentially eliminate the need to build any new power plants, although some may be needed to address regional supply imbalances or upgrade existing power plants. Broadly applied in transportation, buildings, and industry, efficiency technologies could reduce energy use by 15 percent in 2020 and 30 percent by 2030, compared to the Energy Information Administration's "business as usual" reference scenario.
The U.S. has a number of good options for diversifying power generation as well but developing the products to do this will likely raise the price of electricity.
Because the U.S. has good resources, renewable energy from wind, solar, and geothermal could provide an additional 500 terawatt-hours per year by 2020 and 1,100 terawatt-hours per year by 2035. Total U.S. electricity consumption is now about 4,000 terawatt-hours per year.
Coal power plants with carbon capture and storage technology, where carbon dioxide would be stored underground, could replace the entire coal fleet by 2035 through retrofits or new construction. "Evolutionary nuclear technologies" could supply up to 850 terawatt-hours of electricity by 2035 by modifying existing plants and building new ones.
However, to take advantage of more renewable energy and run the system more efficiently will require modernizing the electricity system with smart-grid technologies, which the study says is "urgently needed."
In assessing the transportation sector, the study's authors concluded that petroleum will continue to fuel the country's and trucks in the next three decades, although maintaining domestic petroleum production will be challenging. Once again, the best near-term option to cutting oil consumption is better vehicle efficiency.
Making liquid fuels from biomass, such as wood chips, and from coal with carbon capture and storage could replace about 15 percent of today's fuel consumption. But both approaches still have significant technical barriers. Also, there are potential environmental problems from using large amounts of land for biofuels and coal-to-liquid fuels would increase emissions without carbon capture and storage, according to the study.
Meanwhile, making large numbers of electric light-duty vehicles will require advances in battery performance and fuel cells as well as smart-grid technologies to manage the demand.
The authors of "America's Future Energy" said that emerging technologies need to go through pilot tests in the next five years to demonstrate that they can be commercially viable and done at large scale 10 years from now.
The report said the most high-priority "demonstration stage" technologies are carbon capture and storage, evolutionary nuclear, cellulosic ethanol, and advanced light-duty vehicles. Long-term research and development is required for producing liquid fuels from renewable resources, advanced batteries and fuel cells, large-scale electricity storage, enhanced geothermal, and advanced solar photovoltaics.
To overcome technical and other barriers, the study said that policies and regulations and other incentives need to put in place.
"Actions taken between now and 2020 to develop and demonstrate several key technologies will largely determine options for many decades to come. Therefore, it is imperative that the technology development and demonstration activities identified in this report be started soon, even though some will be expensive and not all will be successful: some may fail, prove uneconomic, or be overtaken by better technologies," according to the report.