Hybrid Electric Cars Such As The Volt
Obviously, electric cars are the future; manufacturers nearly everywhere are jumping on the electric bandwagon, and people are questioning where this leaves the old internal combustion engine. Actually, in an all-electric world the internal combustion engine, redesigned and revamped for service in a supporting role, would still be very important. The supportive role is in evidence in a car like the Chevy Volt. The way battery power functions on the Volt is in some ways the opposite of what happens on a Prius.
The gas-electric hybrid Prius runs primarily on a gasoline-fired engine; the battery and the electric motor only step in when the car runs very low speeds. The electric-gas hybrid that the Volt is, it runs on a battery-powered electric motor at all times, and only keeps a gasoline-fired generator at the back, to keep the battery pack charged should it run out after 40 miles. The Volt is the first of a line of real hybrid electric cars. The gasoline-fired generator doesn't have anything related to turning the wheels. It is a low-speed engine locked in one setting, to provide the most efficient charging possible, is all.
This can be a huge change of school of thought over the way things were done even recently. Better fuel efficiency has always meant tweaking the engine, designing more camshafts or valves for better ventilation; electronics and electricity only came in, finding better ways to control combustion and acceleration more efficiently. So much energy and love put into taming the internal combustion engine, all come to this - running at a set ideal speed, to turn a generator. They don't even get to turn the air conditioner or the power steering. They call such an engine on hybrid electric cars, a range extender. The Volt for instance, uses a four cylinder 1.4 liter engine borrowed from the company's models in Africa, Europe and Asia. Keeping the batteries charged on a Volt needs no more than 50 to 60 horsepower. Ordinarily, a 1.4 liter engine would not be very fuel-efficient if it drove the car by itself.
But every engine has an ideal point, a low speed where it will create the most power for the least fuel, with the least noise and vibration. It will always be somewhere around 2500 rpm. Once hybrid electric cars with range extenders really take off, there'll be dedicated engines built just for battery charging, and they will most likely be half the size of what they use now. Early reviews of the Volt suggest that when the battery runs flat, the range extender engine can be pretty noisy when it kicks in. Pretty soon, lithium-ion battery pack technology will advance far enough to require less and less charging. Until then, the internal combustion engine, still travels with us wherever we go.
