Electricity cheap at Whitall Tatum

ELECTRICITY CHEAP AT WHITALL-TATUM

PLANT — TURBINE GENERATORS EFFECT SAVING

BY USING electricity, generated on the premises, instead of a number of small reciprocating engines, for driving plant equipment and for lighting, the Whitall-Tatum Company, manufacturers of druggists and chemists' glassware, shows, by a recent analysis, a new annual saving of $10,429.42.

In 1920 the plant power was supplied by 22 small reciprocating engines and an investigation was made to determine a better method of drive. As a result, a 300-kilowatt turbine generator was installed in 1921, together with motors to handle the factory load. Six months later a second generating unit was installed for the purpose of using one prime mover as a spare, power being needed at all times.

The turbines are four stage, form B machines each rated 3600 r. p. m., 80 pounds pressure, and operated condensing. The generators are each rated at 375-k-va., 480 volts, 80 per cent. power factor. Both prime movers are of General Electric manufacture.

A recent analysis shows that the annual fixed cost of operating the two generating units is $5,785.23, or $15.85 per average day. When the cost of oil, steam, labor, etc., is added, the total cost per 24-hour is $52.96, or a total cost per generator kilowatt-hour of $0.327. By comparing the coal consumption with that of the previous installation, a saving of 5.73 tons per day is shown, or $11,294.10 per year. The daily saving in labor charges with the new equipment is $5.37, or $1,960.05 per year.

As against the present fixed cost of the turbine installation ($5,785.23), the old engines had a fixed cost of $2,960.50. Thus the present net fixed cost is $2,824.73. This figure, when subtracted from the total savings of coal and labor, shows a net saving of $10,429.42 per year, or a net annual return on the investment in generating equipment of 23.2 per cent. It is estimated that the entire installation will pay for itself in 4-1/2 years.