104 TRANSACTIONS OF THE 
transmitted to Salt Lake City and used for heating pur- 
poses. The losses and efficiencies of the members of this 
system under the best operating conditions, that is, when 
the system would be fully loaded would be about as 
follows: 
LOSSES 
Individual Overall Ind. Efficiency 
Boiler, ash-pit and chimney.......... 25% 25% 75% 
ERIN ao a pons steers o 70% 53% 30% 
RRR OE snes artnet ace bade 5% 1% 95% 
Station uses and minor losses’ .... 10% 2.5% 
Transformers, three sets ............---- 5% 1% 95% 
Transmission and distribution line 
[Ca PSA eer noe ey cerhe Ne aoe 20% 4% 80% 
Total loss from coal pile to heating unit......................-...-...------ 86.5% 
Overall efficiency ‘of systet. 0 ois ce 13.5% 
These are the best results that could be obtained from 
the most up-to-date generating and transmission system. 
They show, that only 13.5% of the energy latent in the 
coal would be delivered to the house electric heater in 
Salt Lake City. This conclusion might be stated in a 
somewhat different way. 
Experience shows that it takes about two pounds of 
soft coal consumed in the most efficient modern steam 
turbo-electric plant to deliver 1 kw. hr. of electric energy 
to a near-by consumer. But two pounds of this coal 
delivers 24,000 B. t. u’s giving 1 kw. hr. or 3412 B. t. u’s 
in electric heat, or 14.2%. 
Now a good house furnace heating system, properly 
managed, has a thermal efficiency varying from 50% to 
65%, which is at least four times the efficiency of the 
steam-electric heating system, and this notwithstand- 
ing the fact that the electric heater itself has an individual 
efficiency of 100%. 
Hence, if it were possibe to install the most modern 
steam turbo-generating plants at the coal mines it would 
require the combustion there of at least four times more 
coal to heat Salt Lake City than is now burned. From 
the stand-point of conservation this waste is not permis- 
sible. 
Now let us look at the problem from the economic 
stand-point. The question arises as to how much electric 
