Contributed by Robert Lyman @ 2015
Robert Lyman is an energy economist and former public servant with 37 years experience assessing energy issues.
Environmentalists who adhere to the theory of human-induced catastrophic global warming are fond of saying that solar energy can soon replace all hydrocarbons in the energy systems of modern economies and that, indeed, this can be accomplished by 2050. This thesis can be tested with reference to the United States, about which there are abundant statistics available.
The U.S. Lawrence Livermore National Laboratory, in cooperation with the Department of Energy, publishes very accurate data concerning the sources and uses of energy in the United States economy. Oil, coal, natural gas, and nuclear reactors produce most of the U.S.’s commercially distributed energy. In 2013, the total energy consumed was 97.4 quadrillion BTUs (thousand trillion British Thermal Units). Of this total, solar energy accounted for less than 0.36% of total production.
The leading solar energy candidate technology to produce significant amounts of power is Concentrated Solar Power with integrated storage. The largest American CSP plant currently built is the Crescent Dune plant in Tonopah Nevada. This plant uses a 540 foot high tower surrounded by 17,500 computer controlled mirrors, each 64 square meters in size, to precisely track the sun and focus the sun’s energy on the solar tower to convert that energy into 1,050 F degree heat to melt sodium nitrate based salts to turn an electro-magnetic generator. The facility takes up 1,600 acres or 6 square kilometers (2.32 square miles) of land. It cost about $1 billion to build and it has a nameplate capacity of 125 MW and a capacity factor of 52%. It can only produce about 485 GWh of power annually at a system cost of U.S. 48.5 cents per kWh (about eight times the cost of a conventional power plant). This plant garnered some unwanted publicity when, during a test of the system, it incinerated 150 birds that happened to fly over during the test.
In order to produce the energy needed to power the United States by 2050 solely from Concentrated Solar Power would take approximately 60,000 plants the size of the Crescent Dune project. Simply to replace the energy that would otherwise be generated by hydrocarbon sources would require almost 47,000 plants the size of the Crescent Dune project.
This breaks down roughly as follows:
20,687 CSP plants to replace current petroleum production & use
15,676 CSP plants to replace current natural gas production & use
10,609 CSP plants to replace current coal production & use
4,87 4 CSP plants to replace current nuclear fission production & use
2,646 CSP plants to replace current Biomass production & use
1,508 CSP plants to replace current hydroelectric production & use
4,000 CSP plants to allow for rotational shutdown and maintenance on a nationwide base of 56,000 operating plants
Critics of the Crescent Dune plant have observed that, even though located in the Nevada desert, it is still located too far north to make optimal use of the sun’s rays. There is virtually no way that one could find either 47,000 or 60,000 sites in the southern United States that would make sense. If you could place them all together (an impossibility), 47,000 plants would take up 108,000 square miles, almost the entire area of the state of Nevada, and it would cost U.S. $47 trillion. 47,000 plants with 17,500 mirrors each would require the manufacture of 822,500,000 mirrors. If we could manufacture one per second, starting right now, it would take 26 years to build that many mirrors.
This is not going to happen. Not by 2050. Not ever.