Page 235 - Handbook of Energy Engineering Calculations

7. Compare engine fuels
Table 9 compares four types of fuels and the internal-combustion engines
using them. Note that where the cost of the fuel is high, the cost of the engine
is low; where the cost of the fuel is low, the cost of the engine is high. This
condition prevails for both large and small engines in any service.

TABLE 9 Comparison of Fuels for Internal-Combustion Engines *

8. Compare the performance of small engines
Table 10 compares the principal characteristics of small gasoline and diesel

engines rated at 7 hp (5 kW) or less. Note that engine life expectancy can
vary from 500 to 25,000 hours. With modern, mass-produced small engines it
is often just as cheap to use short-life replaceable two-stroke gasoline engines
instead of a single long-life diesel engine. Thus, the choice of a small engine

is often based on other considerations, such as ease and convenience of
replacement, instead of just hours of life. Chances are, however, that most
long-life applications of small engines will still require a long-life engine. But
the alternative must be considered in each case.

TABLE 10 Performance Table for Small Internal-Combustion

engines [Less than 7 hp (5 kW)] *