DOE Report on Solar Panels 2004
Name: Jerry F.
Date: July 2004
"The US Department of Energy estimates that a 10-mile by
10-mile square of solar panels located in a place such as Nevada would
generate enough electricity to meet all current power needs of the US."
In the past week I have seen or heard this quote twice, it intrigues me.
Is this a true statement? If so, what report is this from, how can I
acquire a copy of the report? If there is such a report, is there any plan
to act on it?
I am not familiar with the report to which you refer. It sounds encouraging.
However, solar panels are not very efficient and it would indeed require quite a
large array to generate that much electricity. Nevertheless, I am very keen on
developing alternative ways to generate electricity -- solar, wind, geothermal,
tidal, and others -- so that we might move toward a hydrogen-based energy economy
derived from hydrogen produced via the electrolysis of water. Should that day ever
arrive, we would have more than enough domestic oil to meet manufacturing needs
and not have to waste it as a fuel to drive the wheels of industry. Now, how do
we get the folks with the influence to allow it to happen?
This is only about 1% of annual U.S. consumption. Other factors render this
option even less optimistic AS A NATIONAL SOLUTION.
1. The solar flux is total energy at all wavelengths. The atmosphere, clouds, and conversion to
useable energy forms reduces the amount of energy that reaches the surface
of the earth significantly less than the Solar flux.
2. No existing solar conversion technology can make use of all the incident
wavelengths, and even
then the conversion efficiency is small. This is a technological deficiency
not a physical one, and there is a lot of research being done to improve
existing conversion technologies, and find new ones.
3. There are significant losses in the distribution of power from the source to
(electrical resistance in the electrical grid etc.)
4. The solar flux is an average. It can vary (even in Nevada) from cloudiness,
season etc., so some
sort of energy storage system has to be operating to take up the slack
during low flux periods.
5. Building a 10 square mile solar panel is an engineering feat of the first
magnitude. It also has to be fail-safe --
disruptions would cause major problems.
Having said all that I think that solar energy combined with wind technology
could be very efficient on a limited basis -- say to supply a portion of
power to a farm, industry, or even a shopping center. There is much
energy "out there" to be tapped in addition to "fossil fuels". However,
there are also the political problems. Oil producers and refiners are not all
that enthusiastic about replacing their major product -- short sighted (yes)
That number is not right. Assuming 10% overall efficiency, and sited in the
Nevada desert, one can calculate a panel area about 90 miles square would be
Solar insolation is about 5kWhr/day and electric demand in 2000 was about
3.6 terawatt hours.
The actual area covered by the installation would be several times larger.
Yes. See http://www.eere.energy.gov/solar/myths.html
Click here to return to the Engineering Archives
Update: June 2012