Toyota Prius turns twenty

Toyota Prius turns twenty

10th Aug 2017 8:00 am

The Prius is now in its fourth generation, and this year marks 20 years of the world's first mass-produced hybrid passenger vehicle.


The Japanese carmaker launched the Coaster Hybrid EV in August 1997 and the Prius in December of the same year. Since then, global cumulative sales of Toyota hybrid vehicles have surpassed the 10-million vehicle mark at the end of January 2017. Ten million hybrids have saved 77 million tons of CO2 compared to the amount used by a petrol-powered vehicle of the same class. The volume of fossil fuel saved by Toyota hybrids translates into over 1.5 million roundtrips around the earth and the moon!
Toyota launched its first hybrid vehicle 20 years ago, and the circumstances surrounding environmentally friendly vehicles have since changed dramatically. The growing popularity of the Prius led to the creation of a new customer standard of choosing cars based on their environmental performance. As the number of companies developing and launching hybrid vehicles increased, a new segment of ‘hybrid vehicles’ was established. In addition, now that customers around the world are opting to purchase hybrid vehicles and fuel-efficient vehicles, the entire automobile industry has been able to contribute to the solution of global environmental problems. 

"When we launched Prius, no one even knew what a hybrid was. Today, thanks to those early adopters who gave the Prius a chance, hybrids have grown in popularity, and have ridden a wave of success out of the unknown and into the mainstream," said Takeshi Uchiyamada, chairman of the Board of Directors at Toyota and known as the father of the Prius. 

The Toyota Hybrid System (THS), which was incorporated in the first-generation Prius, evolved into THS II in 2003 and was rolled out in a wide range of Toyota vehicles later. The fourth-generation Prius, which became the first vehicle to be built on Toyota New Global Architecture (TNGA 2), was developed with not just environmental performance in mind, but also with an outstanding driving performance for customers who wanted a car that was fun to drive.
Prius concept car at the 31st Tokyo motor show: It was in 1993, when in-house discussions over a ‘vehicle for the 21st century’ intensified, that the development that led to the Prius got under way. In that year, the G21 Project was launched as a means to promote technological development, and, with project general manager Takeshi Uchiyamada at the centre, efforts began toward finding ways to achieve a groundbreaking improvement in fuel efficiency that would light the way.
With the improvement of engine efficiency as its primary objective, the G21 Project at first set a target of raising fuel efficiency performance to 1.5 times the level of conventional engines. However, in a top-down move, Akihiro Wada, the executive vice president for R&D, ordered the high target of a two-fold improvement. In mid-1994, the basic G21 concept was approved, but it was not until it was decided later that a concept vehicle would be shown at the Tokyo Motor Show in 1995 that the hybrid approach entered the picture. A decision was made to give the concept vehicle a hybrid format because a hybrid offered the prospect of doubling fuel efficiency.
But from 1994, when the development of the motor show concept vehicle was started, TMC went ahead with a major change to go in for a hybrid format for the production version as well. Thus, rather than focusing on engine improvement, the project had shifted focus to the adoption of a hybrid system. The upshot was the completion in the autumn of 1995 of a prototype model that was exhibited at the Tokyo motor show and which used a capacitor as the electricity storage device.
1997-2003 First-generation Prius:


1st gen Toyota Prius


The first-generation Prius was launched in October 1997 as the world's first mass-produced hybrid passenger vehicle. With a body compact enough to be registered with a 5-series number plate, the first-generation Prius was a stockier sedan than the current generation. At launch, the first-generation car had a fuel efficiency rating of 28kpl and came with the tagline: ‘Just in time for the 21st century’.
2003-2009 - Second-generation Prius:

The Prius was completely redesigned for the first time in 2003. The new model was equipped with the Toyota Hybrid System II – an evolution of the previous THS – which improved its fuel efficiency rating to 35.5kpl, thereby cementing the image of the Prius as a fuel-efficient vehicle.

The styling was also changed. The highest point of the vehicle was now above the driver's head, and sloped gently downwards in both directions in what was labelled a "triangle silhouette." This new design not only improved aerodynamics but also established an advanced-looking, unique Prius styling.
2009-2015 - Third-generation Prius:


3rd gen Toyota Prius


The third-generation Prius featured a slightly larger body than previous models, and the THS engine was increased in size from 1.5 litres to 1.8. While maintaining the same basic "triangle silhouette" as the second-generation Prius, the hood, headlights, and side view of the new model possessed greater modulation. The third-generation Prius achieved what was then the world's leading 10-15 test cycle fuel efficiency rating of 38kpl.
2015- Fourth-generation Prius:

There were no major design changes from the second to the third-generation Prius. However, the fourth-generation Prius, while inheriting the "triangle silhouette" design, now featured a more aggressive appearance with a lower centre of gravity. The new model combined an outstanding fuel efficiency rating of 40.8kpl in the Japanese JC08 test cycle with a superb performance in a dynamic redesign.
Important development themes for the fourth-generation Prius were to make the hybrid system small and lightweight and reduce transmission loss. A high-revolution motor with higher output density achieved by a new winding method, a transaxle with multi-shaft positioning of the motors, the power control unit positioned directly above the transaxle, along with all other technologies, have been assembled to improve fuel economy and achieve excellent use of space.
The Toyota Hybrid System (THS) has been used in a wide range of Toyota vehicles. Toyota's hybrid technologies, which include fundamental technologies necessary for the development of all its eco-cars, can be combined with a variety of fuels, and the company has positioned these technologies as core environmental technologies for the 21st century. 
Adapting hybrid tech to next-generation eco-cars
In February this year, Toyota announced the launch of the updated Camry hybrid and the Prius for India. The Camry hybrid, the first and the only hybrid model to be manufactured in India, was first launched in India in August 2013 and since then has proven to be more successful than its standard petrol sibling with 95 percent of Camry sales being accounted for by the hybrid version. Until end-June, the Camry hybrid sold a total of 3,404 units.  The Prius, based on TNGA (Toyota New Generation Architecture) platform, which is more of a hybrid technology demonstrator and a CBU import, has sold a total of seven units. 

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