Hybrid Technology: How Does a Prius Work?

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how does a prius work

Your Toyota Prius has paved the way for the hybrid car industry to flourish. A 2020 Toyota Prius Prime has a 54 MPG combined city and highway EPA fuel economy, which increases to 133 MPGe when combined with electric power.

They produce only 1.3 tons per year of tailpipe CO2 emissions (a typical car emits 4.3 tons), save you $5,250 in five years on fuel, and had a drastic rise in popularity, selling over 42 times more vehicles 12 years after the first model’s release. These are all incredible advances, but how does a Prius work?

In this article, we look at how a Prius work. We will analyze Toyota Priuses to determine how a hybrid engine makes your vehicle fuel-efficient.

Prius Design

The design of a Prius impacts its speed by reducing the drag. The shape of your car controls how air flows around the body. Sleeker, aerodynamic models cut through the air to minimize the fuel requirements to reach high speeds because they reduce the resistance experienced.

The Gen 3 Prius had minor changes from the Prius Gen 2. This release has a longer and wider body with sharper corners that improve its wind resistance and decrease drag from 0.26 to 0.25. Even slight reductions in drag coefficients improve the miles per gallon on the vehicle.

The Gen 3 also changed the transmission and engine. The transmission is 20% smaller and lighter, increasing the fuel economy from 48 to 51 MPG. The power and fuel capacities in the engine increased from 76 hp and 1.5 L to 98 hp and 1.8 L.

Another drawing point for the Prius is its energy motor. The vehicle has a multi-function display that monitors how much energy flows between the battery and engine, the battery levels, and the braking systems.

Hybrid Engine: How Does A Prius Work?

You may have purchased your Toyota Prius to save on gasoline. The average 2017 light-duty passenger vehicle has a fuel efficiency of 39.4 MPG, while the 2017 Toyota Prius ranged from 52 to 56 MPG

Assuming gasoline costs $3.00 and you drive 12,000 miles a year, you could spend $642.86 compared to $913.71 for the standard car.

Hybrid engines typically come in series or parallel. In a series hybrid, the gasoline engine charges the car’s battery which powers the electric motor. The gas does not power the wheels directly. In parallel hybrid engines, the vehicle can receive power from the electric motor, gasoline engine, or both.

Series engine hybrids have larger batteries, motors, and generators, which drive up vehicle costs. However, they function better in stop-and-start traffic compared to parallel ones. Parallel hybrids have a better efficiency on the highway.

The Toyota Prius uses the best components of series and parallel engines, making it a series-parallel hybrid.

The Prius has a power split device, which includes a gearbox connecting the generator, gas engine, and electric motor. The Prius Gen 2 was the first to have this device.

A ring gear attaches to the electric motor and transfers the motor’s power to a reduction gear on the final drive. The power split device has a planetary gear set with sun and planet gears.

The gears’ movements power the car and generator. The sun gear spins quickly, and its maximum speed limits the car’s electric capabilities. If the vehicle needs more power than the planetary gears can provide, it turns on the internal combustion engine to use gasoline.

Large engine sizes boost horsepower, which lets the car drive faster. A Prius does not need recharging because the generator acts as a constant power supply for the battery.

Starting From the Stopped Position

As you pull from a stop, the electric motor provides power supplied from the battery. The sun gear will carry the movement until speeds exceed 15 MPH, at which point the gasoline engine kicks in.

When driving in a city or start-and-stop traffic, you will rely on electricity to move your vehicle. Since your gasoline engine will not ignite, you may save on fuel costs.

Braking and Stopping

The Toyota Prius has a regenerative braking system that enables when you release pressure from the gas pedal or apply the breaks.

As the vehicle slows, it cuts power from the gas engine and electric motor. Instead of powering the wheels, it harnesses the kinetic energy from the wheels to charge the generator. The generator turns this energy into electricity that it stores in the battery. 

About 70% of the lost energy can be regenerated into usable energy for acceleration.

The engine and motor switch off at a complete stop. The car uses the battery power to maintain the radio, lighting, air conditioning, and display screens until you start the car again.

Cruising and Acceleration

At steady speeds over 15 MPH, some of the gasoline powers the generator to produce electricity for the batteries.

If you need to accelerate rapidly, the gas engine and electric motor supply extra power to the wheels. The power split device lets them combine their torques to generate more speed. The gas engine allocates some power to the generator for the electric motor to use as needed.

Power split devices can reduce fuel consumption, depending on the planetary gear configuration.

Problems With Hybrid Vehicles

Hybrid vehicles can run into some issues when it comes to their batteries.

Over time, the batteries can no longer hold a charge and need repairs or replacement. Errors in specific cells can also cause your car to run solely on gas, reducing fuel efficiency and driving up gasoline costs.

Battery warranties last eight years or 100,000 miles in most states, whichever comes first. Due to the longevity of Toyotas, many people keep their Priuses much longer than that. 

Still, your battery will eventually lose its ability to store energy and require a replacement.

Read more: How Long Do Hybrid Batteries Last [And How To Know If They Need Replacing]

Hybrid vehicles have unique designs that are challenging to fix. The batteries are closely intertwined with the gasoline engine and electric motors, which complicates the repairs.

Sometimes one or a few modules in a battery will have faulty cells. While replacing the affected modules seems like a sufficient repair, it can lead to problems down the line because the battery is not balanced correctly. 

As a result, you will need to replace your hybrid battery once it starts malfunctioning.

Purchasing a battery from a Toyota dealership can get costly, so you may want to buy your battery from another source. Some people opt for reconditioned batteries, but you can buy new ones for less from reputable sources, like Exclusively Hybrid.

Enjoy the Hybrid Technology

Now that you know how your Toyota Prius works, you can appreciate the innovative hybrid engine every time you are on the road. As long as you make sure your battery is working correctly and replace it in time, you can enjoy years of energy-efficient use with your Prius.