8.1 Introduction................................................................................................ 227
8.2 Natural Gas Properties ............................................................................. 229
8.2.1 Octane Number.............................................................................. 229
8.2.2 Flammability .................................................................................. 230
8.2.3 Wobbe Index ................................................................................... 230
8.2.4 Calorific Value ................................................................................ 231
8.3 CNG Storage ............................................................................................... 231
8.4 CNG Distribution ...................................................................................... 232
8.5 CNG Safety .................................................................................................234
8.6 Engine Tests ................................................................................................ 236
8.6.1 Natural Gas in SI Engines ............................................................ 237
8.6.2 Natural Gas in CI Engines............................................................ 238
8.7 CNG Advantages ....................................................................................... 240
8.8 Challenges for CNG .................................................................................. 241
References............................................................................................................. 241
8
Compressed Natural Gas
Gattamaneni Lakshmi Narayana Rao and
Arumugam Sakunthalai Ramadhas
CONTENTS
8.1 Introduction
Natural gas (NG) is a naturally occurring form of fossil energy and therefore nonrenewable. However, NG has some advantages compared to gasoline and diesel from an environmental perspective. Natural gas vehicles
represent a cost-competitive, lower-emission alternative to the gasoline-fueled vehicle. Utilization of NG as fuel for internal combustion engines was
almost restricted to stationary applications prior to World War II, such as oil
field operations, power generation, and water pumping, where no on-site
fuel storage was required. During World War II, fuel shortages in Europe
resulted in the utilization of several alternative fuels for vehicles, including methane. By the end of the 1960s NG proved that it could contribute to
reducing the emission of air pollutants. The country with the most developed program for the utilization of NG as a fuel for transportation is Italy,
227
8.2 Natural Gas Properties ............................................................................. 229
8.2.1 Octane Number.............................................................................. 229
8.2.2 Flammability .................................................................................. 230
8.2.3 Wobbe Index ................................................................................... 230
8.2.4 Calorific Value ................................................................................ 231
8.3 CNG Storage ............................................................................................... 231
8.4 CNG Distribution ...................................................................................... 232
8.5 CNG Safety .................................................................................................234
8.6 Engine Tests ................................................................................................ 236
8.6.1 Natural Gas in SI Engines ............................................................ 237
8.6.2 Natural Gas in CI Engines............................................................ 238
8.7 CNG Advantages ....................................................................................... 240
8.8 Challenges for CNG .................................................................................. 241
References............................................................................................................. 241
8
Compressed Natural Gas
Gattamaneni Lakshmi Narayana Rao and
Arumugam Sakunthalai Ramadhas
CONTENTS
8.1 Introduction
Natural gas (NG) is a naturally occurring form of fossil energy and therefore nonrenewable. However, NG has some advantages compared to gasoline and diesel from an environmental perspective. Natural gas vehicles
represent a cost-competitive, lower-emission alternative to the gasoline-fueled vehicle. Utilization of NG as fuel for internal combustion engines was
almost restricted to stationary applications prior to World War II, such as oil
field operations, power generation, and water pumping, where no on-site
fuel storage was required. During World War II, fuel shortages in Europe
resulted in the utilization of several alternative fuels for vehicles, including methane. By the end of the 1960s NG proved that it could contribute to
reducing the emission of air pollutants. The country with the most developed program for the utilization of NG as a fuel for transportation is Italy,
227