Diesel engines drive most of the tractors that plow fields and move dirt, and have made a dramatic contribution to the increase in productivity that has exemplified California agriculture since World War II. Diesel fuels the trucks, trains and ships that move most of the freight carried in the state. Buses, which transport two-thirds of the state’s transit passengers, are primarily diesel-powered. Most fire trucks and other heavy emergency vehicles also use diesel. Even the emergency standby generators that powered hospitals and other critical facilities during the 2000-2001 energy crisis are almost exclusively diesel. There is no economic sector in the state that does not benefit from the contribution of diesel power.

Diesel’s advantage over other power sources for these uses is manifold. Compared to alternatives such as gasoline-powered engines, diesel is more energy efficient;

• provides greater power output in large applications;

• is remarkably more durable and reliable; and

• is safer to handle.

Further, diesel is more portable than other alternatives: electric power requires a connection to a source of electricity, and natural gas requires either connection to a pipeline or significant investment in compression and fueling facilities.

Diesel engines are the primary motive force for land and sea-route mass transit as well. Buses, commuter trains and ferries all rely mostly on diesel technology.

Diesel technology is equally important in protecting public safety and ensuring energy reliability. Many emergency vehicles, such as fire and tow trucks, have diesel engines. Hospitals, government offices and businesses often rely on diesel generators for emergency standby power when the power grid suffers an outage.

Figure 1 shows the shares of GSP for each major industry sector in the state.

Figure 3 shows the GSP attributable to output from the diesel technology sectors. These industries produce about $2.3 billion in value added. However, as shown in Table1, California tends to import most of its diesel technology, so that the GSP measure nderestimates the importance of diesel to the California economy.