Allow me to expound on a little noticed technical footnote, initially proclaimed on the insightful site thinkprogress.org:
A recently released study by the National Renewable Energy Laboratory [NREL], estimates that the technical potential of photovoltaic cells and concentrated solar power (CSP) in the United States is as much as 200,000 Gigawatts, enough to generate about 400,000 TWh of energy annually [TeraWatt-Hr].
Here's that US Dept of Energy study:
U.S. Renewable Energy Technical Potentials: A GIS-Based Analysis
by Anthony Lopez, Billy Roberts, Donna Heimiller, Nate Blair, and Gian Porro
NREL is a national laboratory of the U.S. Department of Energy, Office of Energy
Efficiency & Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.
Technical Report
NREL/TP-6A20-51946
July 2012
Contract No. DE-AC36-08GO28308
Here are some very interesting Energy totals, buried in the Appendix of that study:
[pg 32]
Appendix B. Energy Consumption by State
Electric retail sales in the United States were roughly 3,754 TWh in 2010 (EIA) [Energy Information Administration, Dept of Engery].
3,754 TWh (TeraWatt-Hours) --
that would be LESS than the 400,000 TWh of annual solar energy --
potentially available to the US -- a LOT LESS (by a factor of a hundred-times less).
Here are some very interesting conversion factors, from the DesertTec study, that can be used to turn to Energy "Demands" into the equivalent Energy "Supplies" ...
[pg 19]
The largest accessible but least tapped form of energy on earth is solar radiation on deserts. Its capacity, i.e. the annually received amount can be estimated in a rather straight forward way, since radiation is quite uniform across the desert regions. The hot deserts cover around 36 Million km² (UNEP, 2006) of the 149 Million km² of the earths land surface.
The solar energy arriving per 1 year on 1 km² desert is on average 2.2 Terawatt hours (TWh), yielding 80 Mio Terawatt hours/year.
This is a factor of 750 more than the fossil energy consumption of 2005, and there is still a factor of 250 if this demand would triple until 2050.
That works out to roughly speaking
only 659 miles² to provide for
the US annual Electricity consumption (as of 2010). [for this conversion math, check the end of this post.]
How BIG is 659 miles²?
For some land-area ball-park size context:
According to the U.S. Census Bureau, the county [Weber County, Utah] has a total area of 659 square miles (1,710 km²)
Of put another way, a mere 25 miles by 25 miles of desert dedicated to Solar Energy "extraction," could put us on a path that moves our "National Interests" from the generic chaos of Middle East, to the genuine ingenuity of Middle America.
Wouldn't you rather extract sunlight, than extract the increasingly limited supplies of the world's Oil?
Inquiring and peace-loving minds, need to start asking this -- again, unfortunately. Some lessons take a VERY long time to learn.
Boring calculations used to derived the "postage-stamp" sized land area, represented in the previous "Weber County Utah" Solar-equivalent map:
2010 US annual Electricity consumption (in TeraWatt-Hours) X the desert solar conversion factor = Square Kilometers of desert land needed, for the US to achieve Electricity Independence; km² are then converted mi² for the American point of view:
3,754 TWh * (1 km² / 2.2 TWh) = 1706 km² of dedicated desert lands (41.3 km x 41.3 km) would provide for the US annual Electricity consumption (circa 2010).
Or in miles, using the conversion: mi² = km² * 0.3861
More simply put, 658.8 miles² of dedicated desert land (25.6 miles x 25.6 miles) would provide for that US annual Electricity consumption (circa 2010).
1 TeraWatt Hour = 1000 GigaWatt Hours [or 1 TWh = 1000 GWh]
1 GigaWatt Hour = 1000 MegaWatt Hours [or 1 GWh = 1000 MWh]
1 MegaWatt Hour = 1000 KiloWatt Hours [or 1 MWh = 1000 KWh]
KiloWatt Hours are what most of us get charged for, in our monthly Electricity bills. And so the circle (of relevance) is complete.
Here is one more very interesting "conversion factor" graphic, once again from the euro-based DesertTec coalition:
larger image
Which legacy "footprints" would you rather leave on the world?
The chaos of chasing Oil, or the simplicity of catching the limitless Sun?
The generations to follow in our footsteps, would really like to know ...