19 Electric and Hybrid Vehicles P IN PROCESS1 P IN PROCESS2 P IN RAW Distribution from Refineries to Gas Stations Internal Combustion Engine Transmission Axle Refinery 1 7 P O P LOSS1 P LOSS2 P LOSS3 P LOSS4 2 FIGURE 1.9 The complete ICEV process from crude oil to power at the wheels. FIGURE 1.10 2019 US energy usage and generation: (a) energy consumption by end-use sector and (b) electricity generation by source.
TABLE 1.7 Battery Electric and IC Engine Vehicle WTW Efficiencies Battery EV Efficiency (%) ICEV Efficiency (%) High High Low Low Refinery (petroleum) 97 90 85 95 Distribution to fuel tank 99 95 Engine 22 20 Electricity generation 40 33 Transmission to wall outlet 92 90 Battery charger 90 85 Battery (lead/acid) 75 75 Motor/controller 85 80 FC fuel processor PEM fuel cell Plug-in grid/gasoline ratio Transmission/axle 98 98 95 95 Well-to-wheel 20 19 15 14 A sample comparison of EV and ICEV process efficiencies based on the diagrams of Figure 1.8 and 1.9 is given in Table 1.7.
Representative numbers have been used for the energy conversion stages to convey a general idea about the efficiencies of the two systems. Table 1.7 shows that the overall efficiency of an EV is comparable to the overall efficiency of ICEV.