Hybrid Electric Vehicles Explained
Electric vehicles and "The Model E"
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How hybrid electric vehicles work
The Model E hybrid electric vehicle (HEV) delivers more than double the fuel economy of today’s cars by using a “series/parallel” full-hybrid system.
During series operation, the electric motor provides all power to the wheels while the engine either stays off or turns a generator to supply the motor with extra power or to recharge the batteries. Series operation is very efficient in stop-and-go city traffic. During parallel operation the gas engine directly drives the wheels at higher speeds, where it is most efficient.
Because it is designed for both utility and efficiency, the Model E HEV uses a highly efficient, downsized engine, relying on the battery to feed the electric motor to give the vehicle an extra boost to meet or beat the acceleration typical in today’s cars. When a driver steps on the brake pedal of the Model E HEV, the electric motor acts as a generator, sending electricity back to the battery to help recharge it, a process called regenerative braking. If a really quick stop is needed, conventional brakes help slow down the vehicle as well.
The most common battery technology in today’s HEVs is the nickel metal hydride battery (NiMH). Hybrids don’t rely on their batteries to deliver many miles, so instead, the batteries have been optimized for power at a reasonable price. A few automakers are using lithium polymer and lithium ion batteries in their new hybrids and other automakers are considering the adoption of various lithium battery technologies for their next generation hybrids.
Hybrid electric vehicle range on a full charge and full tank
With more than twice the fuel economy of today’s average, the Model E HEV is designed to deliver more miles than a conventional gasoline car with a gas tank of half the size. An optional full-sized gas tank could double the range, cutting visits to the gas station by more than half.
The most fuel-efficient hybrid on the market today, the Toyota Prius, can travel about 600 miles on a tank of gas, one and a half times the range of the typical gasoline vehicle. Unlike the Model E plug-in hybrid electric vehicle (PHEV), the battery of the Model E HEV cannot be recharged via the electrical grid, so it has no all-electric range.
Environmental impacts of hybrid electric vehicles
The Model E hybrid cuts greenhouse gas emissions by more than half compared to the typical car on the road today. It also produces less than one fifth the smog-forming pollution.
Because the Model E HEV does not plug into the electrical grid to recharge, its environmental benefits only vary with your driving style, not the electricity or hydrogen supply in the part of the country it is driven in.