http://www.eesi.org/publications/Fact%20Sheets/EC_Fact_Sheets/Factoid18.pdf.I'm trying to track down what happened to derail publication of this draft document. It is a sketch of the potential of technical of renewables to meet energy needs by the year 2020 assuming a storage medium exists; which it now does with V2G.
You can download the 4 pages at the above link. Here is the preamble from the environmental group that posted it to their website:
RENEWABLE RESOURCES COULD PROVIDE 99 PERCENT OF U.S. ELECTRICITY GENERATION BY 2020:
On January 16, 2006, the Energy Analysis Office (EAO) of the National Renewable Energy Laboratory (NREL) issued for the Office of Science a DRAFT analysis, for comment, of the technical potential for renewables. EAO's preliminary analysis included a summary table representing near-term and ultimate technical potential for renewable
energy resources (economic and market considerations are not taken into account). The seven-page document is entitled "Near-Term Practical and Ultimate Technical Potential for Renewable Resources." The representation for the near term potential is given in percentage of electric generation in the United States in 2020. Near-term potential is restricted by near-term challenges, such as infrastructure and reliability problems, electricity storage, and technological ability to use the resource. Nonetheless, the "near-term practical" potential of renewable resources as a percent of U.S. electricity generation in 2020 is estimated to be 99-124 percent, or - in terms of primary energy - as 47-55 quads/year(electricity only).
The ultimate technical potential is a compilation of previous estimates and calculations based on those estimates. While the analysis assumes some near-term challenges will be overcome, the ultimate potential does account for constraints on technologically insurmountable goals, such as generally accepted restrictions on offshore wind facility distance from shore (200 meters), and on drilling capability for enhanced geothermal systems (10 km of depth). The table suggests that the ultimate technical potential for renewable resources could be as much as 8,529 quads/year.
The resulting estimates offer rough estimates of the potential contributions from renewable resources, not economically or market-feasible projections.
Methodology
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