Hybrid vehicles are a common sight on British roads today but you may not immediately recognise them. You see, the beauty of Hybrid vehicles lies beneath the bonnet - but how do these cost-saving, emissions-beating, mileage-slashing machines work?
The Power of Two
Basically, a ‘hybrid vehicle’ is a vehicle with more than one power source. Most hybrid vehicles use a normal engine paired with an electric motor, but these can work together in three different ways for three different hybrid setups:
A ‘full’ hybrid system uses a battery-powered electric motor and a petrol-driven combustion engine, which can power the vehicle on their own and together. This is the most popular type of Hybrid vehicle in the world and one that Toyota was a pioneer in creating, with the introduction of the original Prius model in 1997. Today, all of our hybrid vehicles are ‘Full’ Hybrid, which includes the Yaris, Auris and Prius range.
The second type of hybrid; known as ‘parallel’, uses a regular combustion engine as the main source of power to drive the vehicle. The electric motor, which is fitted between the engine and gearbox, provides assistance to the combustion engine. Parallel Hybrids are more restricted than a ‘Full’ Hybrid and is limited in power and EV (electric vehicle) range, because the electric motor is fitted into a very small space.
The third variation is the ‘Series’ Hybrid. In this variation, all power is sourced from the electric motor and the normal engine isn’t connected to the transmission, instead working as a generator to power the electric motor. Series Hybrids are rare because once their battery power has been used up they face a hurdle in maintaining their efficiency.
Hybrid Synergy Drive
Our Hybrid Synergy Drive system delivers true synergy between between the two power sources allowing you to switch between one and the other seamlessly.
So What is it?
Hybrid Synergy Drive is Toyota's Hybrid system, used on all hybrid vehicles available at Inchcape Toyota. The Hybrid Synergy Drive system comprises of six main components: a petrol engine, an electric motor, an electric generator, the power control unit, and a power split device. Using a special type of gearbox - the power split device distributes power smoothly from the engine, motor and generator. The intelligent system allows the vehicle to adapt to driving conditions by telling the car how best to combine the two power sources for optimal performance. To get an idea of just how efficient the system is, see it in action below:
01. Starting the Car
All power is taken from the electric motor and the petrol engine remains shut off. This is because the electric motor has low-speed torque at start-off; a petrol engine is not able to produce the same torque in the low rpm range. This allows the electric motor to take control and deliver a smoother, more responsive start.
02. Driving at Low Speed
Unless the battery charge level is low - the electric motor will continue to take over all drive power at low speeds as it’s more energy efficient. If the battery is running low on charge then the petrol engine is used as power to turn the generator to supply power to the electric motors.
The petrol engine becomes the main power source due to its energy efficiency at this speed. Depending on the driving conditions, part of the power is used for the generator while the petrol engine powers the wheels directly. If the battery charge is low then the petrol engine will increase its percentage of power in order to create more electricity to recharge the battery - the car charges as your driving it! If the petrol engine produces more power than is required then the power will be stored in the battery.
04. Full Acceleration
If, for example, your vehicle is climbing a steep slope or overtaking another vehicle then it will be at full acceleration and needs more power. At this stage, the power from the battery will be supplied to the electric motors in order to supplement the power.
When you begin to decelerate, whether it’s braking or lifting the accelerator, Toyota’s hybrid vehicles will use the wheels as regenerators. The kinetic energy of the car allows the wheels to turn the electric motors so energy lost in other vehicles as friction heat is converted into electrical energy that is stored in the battery for later use. When braking, hybrid vehicles are able to capture energy from heat or noise that would usually be lost and 'recycle' it into energy to be used later - this is known as 'Regenerative Braking' and saves you a great deal of energy.
No energy is wasted by idling, that is, leaving the engine running whilst stopped. When a Toyota Hybrid vehicle comes to rest the electric motor, petrol engine and generator automatically shut down. If your running low on battery at this point then the petrol engine will keep running to recharge it.