A hybrid vehicle is any kind of automobile that makes use of two or more systems for propulsion. Today's hybrids use an internal combustion engine and an electric battery and motor.
The dependency of one propulsion system over the other will vary from hybrid to hybrid. Depending on the design, some hybrids will operate more from the combustion engine than the electrical. Others will operate mostly from the electrical battery and motor and only use the internal combustion engine when more power is needed.
The Basic Types of Hybrids:
Mild Hybrids vs. Full Hybrids
A mild hybrid is the hybrid type that must rely on the conventional internal combustion engine for propulsion. The electric motor only acts to assist the internal combustion engine.
Under low load conditions, a full hybrid can propel the vehicle using only its electric motor and battery without even using the internal combustion engine. However, it is only able to do this under certain conditions (usually low load conditions). Under extremely light driving and light acceleration, a full hybrid can run using only the electric motor. If more power is needed for acceleration the internal combustion engine will provide the additional power.
Full hybrids usually get better fuel mileage than mild hybrids, especially in city driving situations since the electric motor is utilized much more than the internal combustion engine in stop and go city traffic.
How Do Plug-In Hybrids Work?
Mild and full hybrids never need to be plugged in.
However, plug-in hybrids are exactly just that - cars that can be plugged in to be recharged. There are a variety of plug-in hybrids still in the planning stages. The Chevrolet Volt Plug-in hybrid takes electric battery powered vehicles to that next level. They are designed to rely on the electric motor for propulsion. The internal combustion engine is only employed as a back-up. This is necessary for the time being until the speed limitations of an all-electric vehicle can be solved.
A plug-in hybrid is meant to be recharged each day by connecting it to a 110-volt household current running out of the wall. They are intended to handle at about 20 to 60 miles of driving or an average commuter distance using only their electric charge stored in the battery. To get around the site in its usual stop and go traffic, the plug in vehicle can rely on the electric motor alone. The internal combustion engine becomes a back-up and increases the mile range if the battery runs low. The combustion engine kicks on and charges the electric battery.
Here's a typical day. You've just purchased your new plug in hybrid. You drive it to commute from home to work and back again. You pull into your driveway and back into your garage. Locate an outlet, plug your vehicle into in your garage and forget about it. You go in your home have dinner, play with your kids, maybe watch your favorite TV show or entertain some friends visiting for the week. After a good night's sleep, your get ready for work the next morning. You go into your garage and find your plug-in hybrid's battery fully charged. All you have to do is unplug your car and drive off to work.
If your daily commute takes you 20 miles each way then you'll never need to employ the internal combustion engine. You can make the trip using electrical power alone! It's possible to drive for weeks without having to use your back up internal combustion engine!
Some people feel that the last thing they want to do is plug their hybrids into a wall when they get home. They feel it's an extra step that they'd rather do without. But, many would agree that plugging your hybrid car into a wall is a very small price to pay for reducing trips to the gas station. Some commuters have to make 2 trips to the gas station a week. Also, what if you're on the road and need to pull into a hotel? Is there a plug in station in the parking lot. This may not be typical commuter behavior but the point is clear. Home may be the only place to plug your car in but in an emergency you may not have that luxury. But your combustion engine should get you out of that bind.
Ultimately, it seems that a plug in hybrid is the best solution for daily commuting. . You will eventually have to buy gas just not as much which has a positive effect on the environment. Less gas usage equal less fuel emissions.
Regenerative braking is a system found in hybrid vehicles that allow you're vehicle to collect and recycle energy that would normally be lost when the vehicle slows down or when you are just coasting. In this system your electric motor is actually running in reverse acting like a generator to recharge the electric battery. Whenever the driver releases the throttle or applies pressure to the brakes, the computer runs the hybrid's electric motor in reverse, literally backwards in order to recharge the electric battery. During longer periods of driving where less braking happens, the combustion engine can run the electric motor to recharge the battery.
Hybrid vehicles are always in a constant state of change when either drawing energy from a charged battery or recharging the battery using a combustion engine. Driving patterns dictate which happens more than the other. Hybrid batteries do not contain lead acid, like the conventional starting battery. They are mostly nickel metal hydride or NiMH. NiMH is a complex but more reliable battery system. NiMH batteries hold the battery charge much longer.
Mild and full hybrids vehicles have the capability to shut down its internal combustion engine. Mild hybrids, however, will only shut off the engine when idle. This saves gas usage and reduces emissions but only if the brakes are being employed such as stopping at a traffic light. Once you release the brakes, the electric engine immediately cuts on and is ready to go immediately.
Hybrid Computer Systems
Merging two completely different drive systems can be quite complex. To get them to run together in a hybrid vehicle requires some complex computer systems. In order for these control systems to operate optimally, they need to be heated or cooled depending on the environmental conditions. These systems must be in a specified temperature range in order for them to function correctly.
The hybrid computer system collects information from various sensors throughout the vehicle such as vehicle speed, engine load and RPM, temperature or gear selection. These systems are programmed to know when the hybrid's battery needs recharging. These computer systems can also determine when the electric motor can run the vehicle on its own and when it needs to employ the aid of the back up combustion engine.
Because of its well designed computer system, the hybrid drives just as well as any conventional automobile.