The Indianapolis times. [volume] (Indianapolis [Ind.]) 1922-1965, 1934-12-13
Today's Science
by DAVID DIETZ-

THE conversion of sunlight into electricity long
Il dream of the scientific world, may become a
reality as the result of research work in prog
reSs at the WESTINGHOUSE Research Laboratories I'M
der DR.. E. D. Wilson.
Scientists have long contemplated the amount
of energy in the sunlight which falls upon the
ground. 1t is this energy. of course. which
the earth and makes it habitable. But except for
that part which is absorbed and directly utilized by
growing plants, the rest goes 70 waste.
1t has been estimated that he energy falling
every second upon square YARD If earth is the
equivalent of one horsepower. II electrical terms
this is about $50 watts
In other words il all the energy of sunlight on a
square ward of earth could be converted into cleo
tricity. it would light 10 75-watt electric lamps.
The first step in the solution of the problem has
been taken by DR.. Wilson. who is one of the West
nghouSe research engineers with the development
of the "photox"
This CELL which converts light into electricity on
small scale is in commercial use in the light
meter. device used by Illuminating engineers to
measure light intenSities
The light meter consists of two parts One is a
small box about the size % average size vanity
case. This is the photoX, photo-votac cell. The
other part consists of ammeter such as you have
on the dashboard of your automobile.
VGTHEN light falls upon the photox. it is con-
w verted into an electric current, which in turn
operates The ammeter The more light received
the larger the current which is developed That is
Why it possible calibrate the meter in terms of
light units instead of electric units
While the photox is extremel accurate and
therefore suitable for a light meter -. Wilson ex
plains its efficiency is not yet SUE Ic make it
suitable a for obtaininr electric current
from sunlight"
The photox is an extremely simple device Es-
sentialy. it is little than fat disk of copper
This disk is heated in air to temperature of 1000
degrees Centigrsde. AS result. the surface is
oXdized, producing a surface of copper oxide.
One might compare the cell the ordinary
electric battery which has electrodes of two metals
and chemical solution" Dr. Wilson says. Our
cell has the two electrodes but chemical solution
The place of the solution is taken by light"
THE action of the cell is simple When light
strikes it. the light waves penetrate the trans
parent gold film and strikes the layer of copper
oxide.
The effect of light upon the copper oxide is to
knock electrons out of the molecules of the oxide
Now electrons the units of negative electricity
These electrons are attracted TO the gold film and
their accumulation upon the film causes it to be-
come electrified negatively
Now an electric current is nothing more or less
than a stream Of eectrons in motion Consequent
". when wire is attached to the gold film and led
TO any electrical device. such the ammeter an
electric current flows from the gold film to the de-
vice and through another wire back to the copper
disk.
AT present working on methods to i'm
prove the construction of the photox" Dr. Wilson
says. This. We hope, will yield to higher output
OF electricity.
we are not trying any other substances because
the copper oxide is extremely durable and We want
yield OF electricity before try other substances"