Until the balance-sheet of some large central-station has been
published, it is impossible to do more than surmise what relation the
earning power of the generating plant bears to the initial cost. Those
central-stations which are working successfully in this country at the
present time are either too small for a reliable estimate to be formed,
or, as in the case of the Grosvenor Gallery, the space is too cramped
for the large amount of machinery which it has been found necessary
to add in order to meet the increasing demands for light. In order to
obtain an approximate idea of the cost of installing a station capable
of maintaining 10,000 lights, the following data (Table III.) given
in Mr. Crompton’s paper before the Society of Telegraph Engineers are
extremely valuable and will be examined with interest.
Although the figures given are necessarily empirical and open to
criticism, the cost with both systems of distribution is approximately
the same, and may be taken roughly at £5,860 per 1,000 lights, which
amount, according to Professor Forbes, would be reduced to £3,914 per
1,000 lights if the installation was put down according to American
practice, and at the initial cost of the Westinghouse alternating
current system.
Mr. Crompton also compares the working cost of the two systems (Table
IV.).