Executive Summary

 

Fuel is used to generate power to turn the engine. Power is needed for a number of purposes: 
1. It takes power to overcome inertial resistance to start the unit moving.
2. Rolling resistance is the tendency for the unit to slow down unless engine power is applied.
3. As the unit moves faster aerodynamic drag resistance (wind resistance) become the big factor. At 63 MPH wind resistance consumes 50% of the available power.
4. Accessories such as air conditioning, thermostatic fans, alternator, air compressor, and power steering pump, ECT. These items use of power varies with engine speed. 
The VTBFEIP (Voluntary Truck and Bus Fuel Economy Improvement Program) has proposed nine areas to reduce fuel consumption.

Fuel is used to generate power to turn the engine. Power is needed for a number of purposes: 1. It takes power to overcome inertial resistance to start the unit moving.2. Rolling resistance is the tendency for the unit to slow down unless engine power is applied.3. As the unit moves faster aerodynamic drag resistance (wind resistance) become the big factor. At 63 MPH wind resistance consumes 50% of the available power.4. Accessories such as air conditioning, thermostatic fans, alternator, air compressor, and power steering pump, ECT. These items use of power varies with engine speed. The VTBFEIP (Voluntary Truck and Bus Fuel Economy Improvement Program) has proposed nine areas to reduce fuel consumption.