Measuring Regenerative Braking Electricity Generated by the City Bus with Internal Combustion Engine

Engine braking, just when the vehicle consumes no fuel, is an important component of the energy balance. In such states, the bus loses its cumulated kinetic and potential energies but alternators recover a portion of these energies into electricity. Simultaneously, electricity consumption in the diesel-engine city bus is a key component of the overall energy balance. A total energy output of receivers can be more than 4 kW. This paper presents the research results on performance of a serial bus driving varied urban routes. The recorded and investigated parameters include a total amount fuel and electricity consumed and an amount of electricity generated. Engine braking states were calculated with a created algorithm. On average, 17% of electricity was generated by bus engine braking. The research results and investigation refer to the entire year.