Zero emission vehicles: Electric and hydrogen cars
The vehicles most capable of dealing with pollution, climate change, and oil security are electric-drive vehicles (EVs) powered by batteries, flywheels, or hydrogen fuel cells. Powered by electric motors they have no combustion engine on board.
As a result, they are Zero Emission Vehicles (ZEVs), at least as far as the vehicle itself is concerned. Of course, somewhere there is an energy plant making electricity or hydrogen, and the emissions of these plants must be evaluated to determine the total impact of the EVs.
How much battery-powered electric vehicles can cut CO2 emissions depends mostly on two factors:
- the electrical efficiency of the vehicles, and
- the emissions from the power plants that produce the electricity used to charge them.
If EVs are charged by electricity from natural gas power plants (steam), carbon dioxide emissions would fall by about 50 percent compared with comparable gasoline vehicles.[59]
In contrast, charging EVs with electricity generated from coal would cut greenhouse gas emissions by only about 20 percent. Charging from oil-fired plants would reduce emissions by about 30 percent.
In the longer term, CO2 and pollution emissions could be entirely eliminated by using renewable energy technologies to charge the batteries.
Regardless of which fuel is used to generate the electricity, EVs could be powered strictly from domestic sources, improving both national security and the nation's balance of trade.
Switching to battery-powered EVs would significantly reduce emissions in urban areas -- EVs emit no street-level pollutants.
If the batteries were charged at night avoiding peak power demands during the day, no new power plants would have to be built. Ozone, which cannot form without sunlight, would be reduced.
No matter how they are recharged, the use of EVs would lead to reduced oil consumption. The greatest reduction would come from recharging them without burning oil.