On The Road Reading: How Much Renewable Potential Does the US Have? Energy Department scientists say 481,800 terawatt-hours and 212,224 gigawatts
How Much Renewable Potential Does the US Have? Energy Department scientists say 481,800 terawatt-hours and 212,224 gigawatts
Herman K. Trabish, August 1, 2012 (Greentech Media)
The newest estimates of U.S. technical potential for renewable energy generation and capacity were reported recently by scientists at the National Renewable Energy Laboratory (NREL), the U.S. Department of Energy research facility.
For the six technologies evaluated, total technical annual generation potential was estimated at 481,800 terawatt-hours and total technical cumulative capacity potential at 212,224 gigawatts. In 2010, aggregate generation sales for all 50 states, according to the report, amounted to roughly 3,754 terawatt-hours.
Good solar resources and large populations make Texas and California the leaders in estimated urban utility-scale PV technical potential. Texas has approximately 14 percent of the annual U.S. technical generation potential forrural utility-scale PV.
California’s combination of population and sun give it the highest annual technical generation potential for rooftop PV.
Texas has 20 percent of the estimated yearly U.S. generation potential for CSP. There is a sharp distinction between states that have potential and those that don’t because of the relatively high resource minimum threshold of 5 kilowatt-hours per meter-squared per day.
Onshore wind power’s technical potential is biggest in the West and central Great Plains, lowest in the Southeast, and present in almost every state. The resource is bigger in the West, but in the Great Plains there are fewer land limitations. Texas leads, with seventeen percent of the nation’s entire annual generation potential.
There is offshore wind power potential off all U.S. coasts. Wind speeds off the Atlantic Coastand in the Gulf of Mexico are lower than off the Pacific Coast, but their wide, shallow continental shelves give them higher development potential. Hawaii leads all states, with 17 percent of the yearly U.S. technical generation potential.
Solid biomass is 82 percent of annual U.S. biopower technical generation potential. Crop residues are the biggest part of that. Landfills provide the biggest portion of gaseous biomass’ contribution to U.S. biopower.
Thirteen states have identified geothermal sites and three times as much potential at yet-to-be-identified geothermal sites. More than 120 times as much annual geothermal generationpotential is estimated to be at undeveloped enhanced geothermal system (EGS) sites in the West. The Rocky Mountain states and the Great Basin region lead in this category.
The Pacific Northwest and Alaska hold approximately 27 percent of the estimated U.S. annual technical generation potential for hydropower.
NREL regularly updates these estimates, which are intended to project the highest likely potential for each of the renewable resources studied.
Technical potential is a technology’s achievable energy generation given (1) system performance, (2) topographic limitations, (3) environmental constraints, and (4) land-useconstraints.
Power density or an equivalent is used to measure performance. That, of course, is subject to revision with advancing technology.
Capacity factor is the measure determined by topographic limitations such as insolation or wind speed. But, once again, as technological capability advances, that measure is subject to revision.
This technical estimate does not consider resource limitations, economic viability or market potential, so it is not a prediction of what will be deployed but of the most that could possibly be deployed.
Technical potential also does not consider transmission availability or costs, or anything to do with transmission reliability, dispatch, loads or policy.
Finally, technical potential estimates are based in part on performance, so as the technologies evolve, their technical potential will also change.