Page 185 - Handbook of Energy Engineering Calculations

Choice of Lube-Oil Cooler for I-C Engines

Determining Solids Intake of I-C Engines

Energy Performance Factors for I-C Engines

Diesel-Engine Volumetric Efficiency

Air-Cooled I-C Engine Choice for Industrial Uses

INTERNAL-COMBUSTION ENGINE PARAMETERS

Internal-combustion (I-C) engines are widely used for power generation in
smaller cities, towns, and isolated sites. Most I-C engines generate less
greenhouse gas than equivalent-capacity coal-fired steam plants. Dual-fuel I-

C engines can use either liquid or gaseous fuels. Such engines are popular in
areas where more than one fuel is available. With dual-fuel capability, the
engine operator can switch from a higher-priced fuel to a lower-cost fuel to
reduce operating costs.

Diesel engines are the most popular I-C type in use today for stationary
installations generating electricity. Spark-ignition gasoline and gas engines
are popular in areas where such fuels are plentiful at low cost, but they are a
minority compared to diesel engines, which are rated as high as 50,000 hp

(37,300 kW).
Stationary diesel engines generating electricity have a typical fuel
consumption of 0.08 gal/kWh (0.30 L/kWh) and a lube-oil consumption of
0.0005 gal/kWh (0.002 L/kWh). Such engines are often fitted with a waste-

heat boiler to capture heat in the engine exhaust. Thus, the diesel engine was
an early entrant in the cogeneration field, and remains prominent today.
A useful rule of thumb for diesel engines is that a diesel-engine waste-heat
boiler can produce 1.9 lb/h (0.86 kg/h) of 100-psi (gage) (689-kPa) saturated

steam at full load per rated horsepower. Steam pressures as high as 150 psi
(gage) (1,034 kPa), and beyond, can be obtained from waste-heat boilers
using diesel-engine exhaust gases. This heat represents about 70 percent of
the available heat in the engine exhaust. About 30 percent of the heat content