Electric Utilities Love Electric Vehicles

• One-third overcomes aerodynamic drag (energy ends up as heat in the air). • One-third overcomes rolling friction (energy ends up as heated tires). • One-third powers acceleration (energy ends up as heat in the brakes).

In contrast to the hundreds of internal combustion engine moving parts, the electric motor has just one. That’s why they’re so efficient. Today’s EV motor efficiencies are typically 90 percent or more. The same applies to today’s solid-state controllers (with no moving parts), and today’s lead-acid batteries come in at 75 percent or more. Combine all these and you have an electric vehicle efficiency far greater than anything possible with an internal combustion engine vehicle.

Even the most wildly optimistic electric vehicle projections show only a few million electric vehicles in use by early in the 21st century. Somewhere around that level, EVs will begin making a dent in the strategic oil, greenhouse, and air quality problems. But until you reach the 10 to 20 million or more EV population level, you’re not going to require additional electrical generating capacity. This is due to the magic of load leveling. Load leveling means that if electric vehicles are used during the day and recharged at night, they perform a great service for their local electrical utility, whose demand curves almost universally look like that shown in Figure 2-4.

How electricity is generated varies widely from one geographic region to another, and even from city to city in a United States region. In 2007, the net electricity mix generated by electric utilities was 48.6 percent coal, 19.4 percent nuclear fission, natural gas 21.5 percent, hydropower 5.8 percent, 1.6 percent and 2.5 percent for geothermal, solar, and wind, with other miscellaneous sources providing the balance (Source: Edison Electric Institute).

Figure 2-4 Weekly peak power-demand curve for a large utility operating with a w eekly load factor of about 80 percent.