n025  1014  02 Nov 80
 
BC-SOLAR
By GLADWIN HILL
c. 1980 N.Y. Times News Service
    DAGGETT, Calif. - In the Victorian era, they called them ''pier
glasses,'' full-length mirrors sometimes mounted on ornate wooden
stands that could be swiveled up and down to highlight milady's
skirt-hem, coiffure or whatever.
    Two of their descendants, each 23 feet square, reared incongruously
from the southern California desert floor last week to a quite
different purpose in an era when concern over hems has been somewhat
eclipsed by concern over fuel shortages.
    Along with 1,816 identical mirrors, to be installed in a rather
spooky druidical circle a half-mile in diameter, they will focus the
sun's rays on a water tank 300 feet in the air to make steam for
electricity.
    Now considered to be the biggest solar energy project in the world,
it is financed with $120 million from the Department of Energy and
$20 million from the Southern California Edison Co.
    ''Solar One'' will, about a year hence, start generating enough
electricity for a community of 6,000 people: 10,000 kilowatts, its
developers say. The facility is enormously expensive, as much as 10
times what it would cost to build a conventional generating plant
with the same capacity.
    The developers say, however, the system's potential for saving in
fuel costs is virtually infinite, and much of the high cost of this
installation has gone into trail-blazing engineering that is expected
to bring down the cost of future facilities incalculably.
    Solar One is expected to save 50,000 barrels of oil a year. If the
unit works as planned, the engineers say, it can be a model for solar
generating facilities ranging from 1,000 to 300,000 kilowatts, 30
times as big as Solar One.
    Construction work here started last January, and the erection of the
first two mirror units was marked last week by dedication ceremonies
attended by 200 Department of Energy officials, industrial executives
and state and local dignitaries.
    ''The decade just passed has been one to try men's souls, especially
those of us in the electric utility industry, as we watched our
options for large-scale generating plants disappear one by one,''
observed the utility's board chairman, William R. Gould. ''But this
decade looks brighter as new technologies become feasible. Solar One
represents just such an option: a promising one.''
    The site was selected, among other reasons, because it has virtually
year-round sunshine. From a boiler atop the tower, steam will be
piped to a conventional generating unit on the ground.
    Even here, however, the sun does not shine at night, raising a
problem of heat storage. The designers' answer to this is a
million-gallon tank containing crushed rock. Circulating oil will
carry enough of the solar hear to this rock, considered an excellent
storage medium, to power the plant through about seven hours of
darkness.
    Solar One, designed by the McDonnell Douglas Corp., will feed into
the utility's existing power system and will essentially serve as a
supplementary power source, in hours of peak demand. But developers
say the system is intrinsically adaptable to other parts of the world
that have less regular sunlight or small-scale power needs.
    The mirrors, called heliostats, are mounted on steel posts a foot in
diameter that are motorized so they can both revolve and tilt the
mirrors to track the sun.
    All the post foundations are now in place, protruding from the
ground in a 75-acre radial array with the eerie appearance of a huge
drive-in movie theater. Three 50-foot segments of the central tower
stand on the sand, waiting to be assembled.
    
ny-1102 1314est
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