Have you recently driven your car to the pump and been shocked by the high price of gas? Maybe you’ve been thinking about trading in your car for something with better mileage, or maybe you’re worried your car is contributing to global warming, but you’re not ready to go all-electric just yet.
Enter the hybrid car. But how do hybrid electric cars work?
What’s going on under the hood that allows you to get 20 or 30 miles per gallon more than a regular gas car? And does it pollute less just because it has better fuel economy? And where does the plug-in hybrid come into play?Hybrid Car
In this article, we will help you understand how this technology works and also give you some tips on how to drive a hybrid car with maximum efficiency.
Gasoline power versus electric power
Let’s start with some differences between a petrol car and a regular electric car.
A gasoline car has a fuel tank that supplies gasoline to the internal combustion engine. The engine then drives a gearbox which turns the wheels.
An electric car, on the other hand, has a set of batteries that power an electric motor. The engine drives a gearbox and the gearbox drives the wheels.
The hybrid is a compromise. The goal is to significantly increase mileage and reduce emissions from a gasoline-powered car while offering the convenience of refueling at the gas station.
Petrol-electric hybrid structure
Petrol-electric hybrid cars contain the following components:
Petrol engine: The hybrid car has a petrol engine similar to the petrol engine found in most cars. A hybrid car’s engine, on the other hand, is smaller and makes use of cutting-edge technology to boost efficiency and cut emissions.
Fuel tank: The fuel tank in a hybrid vehicle is the energy storage for the gasoline engine. Batteries are not nearly as energy dense as gasoline. For instance, 454 kg of batteries are needed to store the same amount of energy as 3.8 gallons of gasoline.
Electric motor: The electric motors in hybrid cars are very advanced. Advanced electronics ensure that it can function as both motor and generator. If necessary, it can, for example, draw energy from the batteries to accelerate the car. However, since it acts as a generator, it can slow the car down and return energy to the batteries.
Generator: The generator is similar to an electric motor, but only produces electrical power. It is usually used on serial hybrids.
Batteries: The batteries in a hybrid car store the energy for the electric motor. Unlike the gasoline in the fuel tank, which can only power the gasoline engine, a hybrid car’s electric motor can both input energy and take energy from the batteries.
Transmission: The transmission of a hybrid car fulfills the same basic function as the transmission of a conventional car. Some hybrids, such as the Honda Insight, have conventional transmissions. Others, like the Toyota Prius, are radically different.
Parallel hybrids
You can combine the two power sources in a hybrid car in different ways. An alternative, known as a parallel hybrid, has a fuel tank that supplies gasoline to the engine and a set of batteries that power the electric motor.
Both the engine and the electric motor can drive the transmission at the same time, after which the transmission drives the wheels.
Series hybrid
In a series hybrid, the gasoline engine drives an alternator, and the alternator can charge the batteries or power an electric motor that drives the transmission. The petrol engine therefore never drives the vehicle directly.
Performance for a hybrid car
The advantage of a hybrid vehicle is that its gasoline engine can be significantly smaller and more efficient than that of a traditional vehicle. Most cars require a relatively large engine to produce enough power to accelerate the car quickly.
But with a small engine, efficiency can be improved by using smaller, lighter parts, reducing the number of cylinders and running the engine closer to its maximum load.
Why are smaller engines more efficient?
There are several reasons why smaller engines are more efficient than larger ones.
Every time the car accelerates or climbs a hill, the larger engine needs to expend more energy due to its weight.
The pistons and other internal components are heavier and require more energy each time they move up and down the cylinder.
The displacement is greater, which means that more fuel is required per cylinder.
Larger engines usually have more cylinders, and each cylinder uses fuel every time the engine starts, even when the car is not running.
This explains why two identical car models with different engines can achieve different mileage. If both cars are driving on the highway at the same speed, the car with the smaller engine uses less energy.
Both engines must produce the same amount of power to power the car, but the small engine uses less power to propel itself.
Get enough strength
How can this smaller engine deliver the power your car needs to compete with the more powerful cars on the road?
Let’s contrast our hybrid vehicle, which has a modest gas engine and an electric motor, with a vehicle like the Chevy Camaro, which has a large V8 engine. The Camaro’s engine has more than enough power to handle any driving situation.
The engine in the hybrid car is powerful enough to propel the car on the highway, but when it comes to driving the car fast or going up a steep hill, it needs help. This “help” comes from the electric motor and the battery – and this system intervenes and provides the necessary extra power.
A conventional car’s petrol engine is designed for maximum power demand (the few times you press the gas pedal). In fact, most drivers use their engines peak performance less than one percent of the time.
The hybrid car uses a much smaller engine that meets average power requirements rather than peak performance.
Improve fuel economy in 5 different ways
In addition to a smaller, more efficient engine, today’s hybrids use many other tricks to increase fuel consumption. Some of these tricks help reduce fuel consumption for all types of vehicles, while others are unique to hybrid vehicles.
1- Recover energy and store it in the battery
When you press the brake pedal in your car, you take energy from the car. The faster a car goes, the more kinetic energy it has.
A car’s brakes absorb this energy and release it as heat. Some of this energy can be captured by a hybrid vehicle and stored for later use in the battery.
This is done by using a “regenerative braking system”. This means that the electric motor that drives the hybrid drive can not only stop the car with the brakes, but also brake it. In this mode, the electric motor acts as a generator that charges the batteries while the car slows down.
2- Sometimes the engine stops
A hybrid car does not have to constantly rely on the gasoline engine because it has an alternative energy source: the electric motor and the batteries. The hybrid car can therefore sometimes switch off the petrol engine, for example when the vehicle is stopped at a red light.
3- Using advanced aerodynamics to reduce drag
When you’re driving on the highway, most of your engine’s work is pushing the car through the air. This force is called aerodynamic drag.
This resistance can be reduced in various ways. A safe way is to reduce the front part of the car. Consider how a large SUV has to move a much larger area through the air than a small sports car.
Reducing or eliminating interference around objects protruding from the car can also help improve aerodynamics. For example, covering the wheel arches dampens airflow and reduces drag.
4- Use of tires with low rolling resistance
Most car tires are optimized to drive smoothly, minimize noise and provide good grip in a variety of weather conditions. However, they are rarely optimized for efficiency.
In fact, the tires cause a surprising amount of resistance when driving. Hybrid cars use special tires that are both stiffer and have higher pressures than traditional tires. The result is that they provide less air resistance than regular tires.
5- Use lightweight materials
Reducing a car’s overall weight is an easy way to increase mileage. A lighter vehicle uses less energy every time you accelerate or climb a hill.
To reduce weight, composite materials such as carbon fiber or light metals such as aluminum and magnesium can be used.
The power sharing unit
The power split unit is the heart of the Toyota Prius, the most famous hybrid vehicle. This is an intelligent transmission that connects the gasoline engine, the generator and the electric motor.
This allows the car to function as a parallel hybrid: the electric motor can drive the car by itself, the petrol engine can drive the car by itself, or both can drive the car together.
Thanks to the power distribution, the car can also be driven as a series hybrid; The gasoline engine can operate independently of the vehicle’s speed, charging the batteries or driving the wheels as needed.
It also operates as a continuously variable transmission (CVT), eliminating the need for a manual or automatic transmission. Finally, the car does not need a starter motor because the power split device allows the alternator to start the engine.
The power split unit is a planetary gear set. The electric motor is connected to the gear set. It is also directly connected to the differential that drives the wheels. The speed at which the electric motor and gear rotate determines the speed of the car.
The generator is connected to the sun gear of the gear set and the motor is connected to the planetary gear carrier. The speed of the ring gear depends on all three components, so they must all work together at all times to control the output speed.
During acceleration
the electric motor and batteries initially provide all the power. The power distribution device’s ring gear is connected to the electric motor so that it begins to rotate with the motor.
The planet carrier connected to the motor is stationary because the motor is not running. As the ring gear rotates, the planets must also rotate, causing the sun gear and generator to rotate. When the car accelerates, the generator runs at the desired speed and keeps the engine off.
When you reach about 40 km/h, the petrol engine starts. The generator suddenly changes speed, causing the planet carrier to rotate and the engine to start.
Once the engine is running, it sets a constant RPM while the alternator adjusts its speed to the output speed of the electric motor.
When you accelerate really hard, the engine draws additional power from the batteries. Once you reach highway speeds, the car runs on a combination of gas and electricity, with all power coming from the alternator.
How much horsepower do you need?
The amazing thing is that most of what we expect from a car only uses a small percentage of its horsepower. When you’re driving on the highway at 60 mph (96.6 km/h), your car’s engine must provide power to do three things:
Overcome the resistance created by pushing the car through the air
Overcome all friction in vehicle components such as tires, transmission, axles and brakes
Electrical accessories such as air conditioning, power steering and headlights
For most cars this requires less than 20 hp. So you can “put it on the ground”, which is the only time you need to use that much force. The rest of the time, you use significantly less electricity than you have available.
Hybrid mileage tips
The driver’s desire for quick acceleration makes our cars far less efficient than they could be. You may have noticed that a car with a less powerful engine gets better fuel economy than an identical car with a more powerful engine. (Just look at the window decals on new cars at a dealership for a comparison of city and highway MPG.)
How to get the best mileage
You can get the best mileage out of a hybrid car by practicing the same driving habits that result in better mileage in your gas-powered car.
Slow down. The car’s air resistance increases dramatically the faster you drive. For example, the thrust at 70 mph (113 km/h) is roughly double that at 50 mph (81 km/h). So keeping your speed low can increase your mileage significantly.
Maintain a constant speed. Every time you accelerate the car, you use energy, some of which is wasted when you slow the car down again. By keeping a constant speed, you get the most out of your fuel.
Avoid sudden stops. When you stop your car, the electric motor in the hybrid acts as a generator, drawing some of the energy from the car as it slows down. If you give the electric motor more time to brake the vehicle, it can recover more energy. If you stop quickly, the car’s brakes do most of the work slowing the car down, and that energy is wasted. The same reasoning applies to gasoline-powered cars: stopping abruptly wastes a lot of energy.
How to get the best mileage
You can get the best mileage out of a hybrid car by practicing the same driving habits that result in better mileage in your gas-powered car.
Slow down. The car’s air resistance increases dramatically the faster you drive. For example, the thrust at 70 mph (113 km/h) is roughly double that at 50 mph (81 km/h). So keeping your speed low can increase your mileage significantly.
Maintain a constant speed. Every time you accelerate the car, you use energy, some of which is wasted when you slow the car down again. By keeping a constant speed, you get the most out of your fuel.
Avoid sudden stops. If you give the electric motor more time to brake the vehicle, it can recover more energy. The same reasoning applies to gasoline-powered cars: stopping abruptly wastes a lot of energy. read more