Matthew Stepp's analysis of an NREL Renewables study appeared here and in The Washington Post on April 5th.
His commentary on the potential for renewable energy to meet climate change reductions was limited to a narrow study. I routinely hand out 25 studies released in the last few years to my students, that in aggregate, conclude that the world and the U.S. can meet most-or-all of their energy needs with commercially available high-value energy efficiency and renewable energy technologies.
The most recent studies on renewable energy contributions do not address the potential of high-value energy efficiency.
For example, energy efficient motors, super-insulated and electrochromic windows, solar daylighting, LEDs/CFLs, higher-insulated buildings, and combined heat and power (waste heat) could easily save or meet over 20 percent of U.S. energy needs and use according to the American Council for an Energy Efficient Economy (ACEEE).
Most energy efficiency analysis does not always include renewable thermal technologies — solar heating and cooling, geothermal heat pumps, wood pellets and bio-fuels, trombe walls and other passive solar building features — all of which could cut U.S. energy demand by at least another 10 percent.
Base-load renewable energy (capable of supplying power 24-hours a day) can provide the U.S. (conservatively) 10 percent through geothermal according to an MIT study, 10 percent by marine energy, which includes freeflow hydropower, tidal, wave, and ocean thermal and currents (EPRI group study), and 18 percent by waste biomass including landfill gas, food processing wastes and contaminated grains, animal manures and poultry litter, human sewage and food wastes, and forest slash and thinnings that are not able to be absorbed by the forest floor (ORNL report).
Concentrated solar power (CSP) located in U.S. deserts actually has the capacity to meet all our electricity needs from a resource standpoint and can also supply baseload power when it uses molten salts and other thermal storage. Assuming transmission limitations and costs, CSP could conservatively, but practically, provide 10 percent of U.S. electricity needs.
Most studies do not point out that many variable renewbles naturally coincide with season and peak electric power rates, ratchet rates, and/or lower utility demand charges. According to Energy Self-Reliant States, a resource of the Institute for Local Self-Reliance's New Rules Project, “customers in San Francisco on a time-of-use pricing plan pay more for electricity during peak hours (12 noon to 6 p.m.). In the cold months (November through April), the peak rate is 11.1 cents per kilowatt-hour (kWh), compared to 8.3 cents during non-peak hours. But in the warm months (May through October), electricity used from 12 noon to 6 p.m. costs 31 cents per kilowatt-hour (kWh), while off-peak electricity is 7.9 cents per kWh.”
Variable solar, meaning concentrated solar power without storage and photovoltaics, both utility-scale and distributed on-site generation can meet a minimum of 12 percent of U.S. needs according to studies by Navigant, Google.org and others. And the National Renewable Energy Laboratory studies have shown that onshore and offshore wind power could supply 20 percent of U.S. electricity needs. In many areas of the U.S., these sources offset ‘naturally’ higher cost (and polluting) energy from older peak generating plants or are wheeled from utilities far away incurring line losses.
A great many of these reports fail to incorporate higher-value energy efficiency that can meet thermal needs such as waste heat and renewables, passive solar building materials, and solar daylighting — this is a huge energy resource, which my colleague Amory Lovins eloquently labeled “negawatts.”
Most of the analysis reports, including many of “my 25 top studies” also leave out certain renewables. The entire portfolio is the asset, not just part of the recipe — like a pizza without crust or a soup without broth — not acceptable. But they gloss over it — and we all accept it.
What is so nice about this blended energy scenario, is that we are not putting all our eggs in one technology basket, the energy sources are smaller and more geographically dispersed than the traditional larger-scale electricity generation, and are closer (in most cases) to the end users so there are less line losses and greater cradle-to-grave positive energy balances.
The reduction in water use is an important asset, since energy is the largest user of water, and we are at the beginning of a 50 year drought and more intense weather patterns due to a changing global climate. Wastes are minimal compared to what we are experiencing from unusable water (fracking), radioactive nuclear waste, and coal ash — a Sierra club study identified 39 additional coal ash dumpsites in 21 states that are contaminating water supplies with heavy metals. The government is inadequately monitoring these disposal sites and lax at regulating the toxic waste, according to IN HARM’S WAY: Lack of Federal Coal Ash Regulations Endangers Americans and Their Environment (PDF).
These resources are renewable and not tied to global commodity trading with unexpected increases, minimal greenhouse gas emissions as well as minimal regulated emissions under the Clean Air Act — NOx, SO, mercury and particulates. And contrary to popular notions — all are manufactured in the United States with subsidies one tenth of what the conventional energy industries receive.
So what's wrong with this picture? Not the science. Not the business case. Not the pubic opinion. Just the political will. But the deficits in our energy analysis by selectively cherrypicking only part of the sustainable energy picture just adds to the confusion and does not propel us to a sustainable future.
Lead image: Missing puzzle pieces via Shutterstock