COMPARISON OF RESULTS OBTAINED FROM 
STEAM AND PRODUCER-GAS TESTS. 
By Robert H. Fernald and L. P. Breckenridge. 
STEAM PLANT. 
The accompanying table, showing the comparative results of burn-' 
ing the various coals under the boiler and in the gas producer, is oi 
much interest and value. 
It is to be recollected that the steam generated b}^ the boiler wad 
used in a simple noncondensing engine of the Corliss type, whosq 
u water rate" was 26.3 pounds of steam per hour per horsepowea 
developed; that this engine was belted to the electric generator, anj 
that the mechanical efficiency of this combination of engine anl 
generator was 81 per cent. 
With these figures available it will be an easy matter to calculate 
the number of pounds of coal which would have been required to pro] 
duce an electrical horsepower provided a more economical type of 
steam engine had been used, or if the electrical generator had been 
directty connected to the engine, with the resulting advantage of J 
higher mechanical efficiency. 
If, for example, the steam generated had been used i>y a steam 
engine capable of generating 1 horsepower with 18 pounds of steam 
per hour, and if the engine and generator had been direct connected,! 
giving as high a mechanical efficiency as 90 per cent, then the u Total i 
dry coal per electrical horsepower per hour " would have been reduced 
from 4.3 pounds, as given in column 13, to very nearly 3 pounds. 
While these figures are frequently and easily attained by stean 
engines operating in large units, it will be conceded that in plants 
from 200 to 250 horsepower they are but seldom reached. 
It should be mentioned that the labor required would be the sam< 
for the operation of either the boiler plant or the gas-producer plan 
of the capacity under tests. In either plant two men would b 
sufficient. 
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