8 
BULLETIN 1348, U. S. DEPARTMENT OF AGRICULTLTIE 
Approximate power units, primary horsepower, horsepower-hours, and cost of 
power utilized annually on farms in the United States 
Kind of power 
Total 
units 
or in- 
stalla- 
tions 
Aver- 
age 
pri- 
mary 
horse- 
power 
per 
unit 
Total 
primary 
horsepower 
Aver- 
age 
horse- 
power- 
hours 
per pri- 
mary 
horse- 
power 
per 
year 
Total horse- 
power-hours 
utilized an- 
nually 
Aver- 
age 
cost 
per 
horse- 
power- 
hour 1 
Total annual 
cost of power 
developed 
Thou- 
sands 
20, 770 
400 
2.95 
20 
10 
50 
20 
25 
2.75 
.5 
3 
4 
25 
Thou- 
sands 
19, 800 
8,000 
3 4, 000 
2,500 
7,120 
500 
6,800 
500 
900 
800 
500 
Per 
cent 
41.8 
16.9 
""5."3" 
15.0 
1.0 
14.4 
1.0 
1.9 
1.7 
1.0 
490 
88 
225 
400 
80 
1,000 
220 
400 
U67 
190 
1,200 
Millions 
9,700 
700 
900 
1,000 
600 
500 
1,500 
200 
M50 
150 
600 
Per 
cent 
60.6 
4.4 
5.6 
6.4 
3.7 
3.1 
9.4 
1.3 
.9 
.9 
3.7 
0.25 
.06 
.125 
.06 
.20 
.04 
.08 
.05 
i.25 
«. 15 
«.05 
Million 
dollars 
2,425 
42 
112 
60 
120 
20 
120 
10 
38 
23 
30 
Per 
cent 
80.8 
Gas tractors: 
Belt 
1 4 
3.7 
Steam tractors 
50 
356 
20 
2,480 
1,000 
300 
200 
20 
2 
Motor trucks 
4 
Stationary engines: 
Large 
7 
Small 
4 
Windmills 
. 3 
Electric power: 
Individual plants 
Central station, small . 
Central station, large- 
1.3 
.8 
1.0 
Total 
47, 420 
100.0 
320 
16,000 
100.0 
.19 
3,000 
100.0 
1 Based on 1924 average values and includes interest, depreciation, taxes, insui-ance, housing, repairs, 
feed, fuel, oil, and care when not in use but does not include wages of operator while in actual use. The 
values computed for the different kinds of power are not directly comparable, since the natm-e of the work 
done and the load factors obtained are not identical in each case. 
2 The power of a 1,200-pound horse or mule has been considered as equal to 1 primary horsepower, and 
the power of larger or smaller work animals has been computed on the assumption that it is proportional 
to their weight. 
3 Gas-tractor drawbar power is included under belt power in the total. 
* Represents input, not output. 
* Rate based on power input, not on output. 
Estimated utilization of power developed on farms annually, by operations and 
nature of work accomplished 
Type of operation 
Draft work: 
Road hauling 
Farm hauling 
Plowing and listing 
Fitting ground 
Planting and seeding 
Cultivating 
Harvesting 
Hajdng.. 
Miscellaneous field work 
Total draft work 
Stationary work: 
Threshing 
Pumping (irrigation and drainage) 
Pumping (domestic) 
Operating isolated electric plants.. 
Grinding feed 
BaUng hay 
Shredding feed 
Sawing 
Shelling corn 
Cutting silage 
Miscellaneous 
Total stationary work 
Total, all farm operations 
Estimated 
power uti- 
lized an- 
nually 
Percent- 
age of 
each type 
Percent- 
age 
of total 
Thousand 
horsepower- 
hours 
Per cent 
Per cent 
2, 400, 000 
21.2 
15.0 
1, 200, 000 
10.6 
7.5 
2, 500, 000 
22.1 
15.6 
1, 000, 000 
8.9 
6.3 
400, 000 
3.5 
2.5 
1, 000, 000 
8.9 
6.3 
800,000 
7.1 
5.0 
900,000 
8.0 
5.6 
1, 100, 000 
9.7 
6.8 
11,300,000 
100.0 
70.6 
1,200,000 
25. 5 
7.5 
1,000,000 
21.3 
6.3 
600, 000 
12.8 
3.7 
150, 000 
3.2 
1.0 
200,000 
4.3 
1.3 
100,000 
2.1 
.6 
100,000 
2.1 
.6 
100,000 
2.1 
.6 
80,000 
1.7 
.5 
50,000 
1.1 
.3 
1,120,000 
23. S 
7.0 
4, 700, 000 
100.0 
29.4 
16, 000, 000 
100.0 
