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Re: ots of responses, one email, easy deleting, low in calories
November 21, 2001
Davis, CA
Sure, there are theoretically large amounts of wind power out there, and
solar power, too, but the distribution is erratic and the energy density is
very dilute. It is not practical to try to harvest these so-called
renewable energy sources, because the distributed energy cannot be
efficiently collected. It may be easy to conclude that there is enough wind
and direct solar power to meet our electrical energy needs, but the truth
is that it is not in a usable form. So the statement "THERE
SIMPLY_ARE_NOT_ENOUGH 'RENEWABLES' PERIOD!!!" may be wrong with respect to
the total energy present but it is correct with respect to its potential
usefulness.
(1) Wind power stations can only supply a meager amount of electricity
because the fraction of the wind power that can be captured is tiny. In
California we have examples of these power "stations". The fraction of the
wind power that passes them that is harvested is obviously very small.
Besides being rather ugly, these units are deadly to birds, and they occupy
considerable open space per unit of recovered energy. There is probably a
high breakdown rate because of their mechanical features, for I have
observed that a large fraction are usually out of service. Finally, the
deaths and injuries to people per MWh of electricity are probably much
higher than for other technologies. There have been electrocutions to
maintenance workers trying to repair these windmills. I do not have costs
of construction and repair, but my guess is that, as with solar, the cost
of construction and operation of these units leads to much higher energy
costs than from other technologies.
(2) The sun's rays are too dilute and intermittent for efficient use for
electrical power. With current technology it would require covering an area
of about 25 square miles with collectors and support roads to produce a
1,000 MWe system, that only works when the sun is shining. Here in
California we have lots of sun, but there are still only about 5 to 6 hours
per day in which solar power reaches peak levels. Also, think of the
environmental consequence of virtually destroying all the plant and animal
life on 25 square miles of land to equal one 1,000 MWe power plant that
shuts down every night and in bad weather. That's not an environmentally
sound approach. California would need to cover 1,000 square miles with
collectors to meet its electrical energy needs. Maybe we could use the
Mohave desert, but what about the endangered species and plants? The
so-called environmentalists complained about use of just a few hundred
acres for the Ward Valley LLRW disposal facility. More efficient collectors
would help somewhat, but solar to electrical conversion efficiency probably
will continue to be severely limited. With current technology, the cost of
collectors in terms of energy consumed and materials used in manufacture
probably exceeds the electrical energy value of ten to twenty years of use,
even assuming no breakdowns or repair costs. Consequently, commercial solar
electricity per MWh will great exceed the cost of nuclear power. Solar has
not been not cost effective, even for home roof systems, since costs
greatly exceed their power generation value. Most that have been built were
built with government (tax-payer) subsidies. They are still not a good
investment now.
Otto
**********************************************
Prof. Otto G. Raabe, Ph.D., CHP
Center for Health & the Environment
(Street Address: Bldg. 3792, Old Davis Road)
University of California, Davis, CA 95616
E-Mail: ograabe@ucdavis.edu
Phone: (530) 752-7754 FAX: (530) 758-6140
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