Toyota Prius is a full hybrid electric automobile developed and manufactured by Toyota Motor Corporation since 1997. Initially offered as a 4-door sedan, it has been produced only as a 5-door liftback since 2003.

In 2007, the United States Environmental Protection Agency (EPA) and California Air Resources Board (CARB) rated the Prius as among the cleanest vehicles sold in the United States, based on smog-forming emissions. The 2018 model year Prius Eco ranks as the second-most fuel efficient gasoline-powered car available in the US without plug-in capability.

First generation (XW10; 1997–2003)

In 1995, Toyota debuted a hybrid concept car at the Tokyo Motor Show, with testing following a year later. The first Prius, model NHW10, went on sale on 10 December 1997. The first-generation Prius (NHW10) was available only in Japan, though it has been imported privately to at least the United States, United Kingdom, Australia and New Zealand.

The first-generation Prius, at its launch, became the world’s first mass-produced gasoline-electric hybrid car. At its introduction in 1997, it won the Car of the Year Japan Award, and in 1998, it won the Automotive Researchers’ and Journalists’ Conference Car of the Year award in Japan.

NHW11 (2000–2003)

The Prius NHW11 was the first Prius sold by Toyota outside of Japan, with sales in limited numbers beginning in the year 2000 in Asia, America, Europe and Australia. In the United States, the Prius was marketed between the smaller Corolla and the larger Camry. The published retail price of the car was US$19,995. European sales began in September 2000. The official launch of the Prius in Australia occurred at the October 2001 Sydney Motor Show, although sales were slow until the NHW20 (XW20) model arrived. Toyota sold about 123,000 first-generation Prius.

Second generation (XW20; 2003–2009)

Presented at the April 2003 New York International Auto Show, for the 2004 US model year, the NHW20 Prius was a complete redesign. It became a compact liftback, sized between the Corolla and the Camry, with redistributed mechanical and interior space significantly increasing rear-seat legroom and luggage room. The second-generation Prius is more environmentally friendly than the previous model (according to the EPA), and is 6 inches (150 mm) longer than the previous version. Its more aerodynamic Kammback body balances length and wind resistance, resulting in a drag coefficient of Cd=0.26. The development effort, led by chief engineer Shigeyuki Hori, led to 530 patents for the vehicle.

Third generation (XW30; 2009–2015)

Toyota debuted the new Prius (2010 US model year) at the January 2009 North American International Auto Show, and sales began in Japan on May 18, 2009. Toyota cut the price of the Prius from ¥2.331 million to ¥2.05 million to better compete with the Honda Insight, leading some to wonder whether increased sales of the Prius might come at the expense of sales of other vehicles with higher margins. Competition from lower priced hybrids, such as the Honda Insight, also made it difficult for Toyota to capitalize on the Prius’s success. As of June 2013, Toyota has sold about 1,688,000 third-generation Prius worldwide.

Awards

At its introduction in 2009, it won the Car of the Year Japan Award for the second time. In December 2013, Consumer Reports named the Prius as the “Best Value”, for the second year in a row. A 2019 iSeeCars study ranked the Prius as the second longest-kept vehicle among U.S. drivers.

Fourth generation (XW50; 2015-present)

The fourth-generation Prius was first shown during September 2015 in Las Vegas, and was released for retail customers in Japan on December 9, 2015. The launch in the North American market occurred in January 2016, and February in Europe.

In August 2013, Toyota Managing Officer Satoshi Ogiso, who was chief engineer for the Prius line, announced some of the improvements and key features of the next generation Prius. This was the first generation of the Prius to use the Toyota New Global Architecture (TNGA) modular platform, which provides a lower center of gravity and increased structural rigidity. Ogiso also explained that the next-generation Prius plug-in hybrid, the Prius Prime, was developed in parallel with the standard Prius model.

2018 facelift model

In late November 2018, for the 2019 model year, the U.S. market Prius lineup introduced an all-wheel drive model featuring Toyota’s E-Four system. This has been available for the Japanese market Prius since 2015 and the hybrid versions of the RAV4 and Lexus NX. Also, the Prius received a facelift with redesigned headlights and taillights, which was released in Japan on December 17, 2018.

Prius family lineup

Prius Plug-in Hybrid
Prius Prime
Prius v
Prius c

Prius Plug-in Hybrid

The Prius Plug-in Hybrid (ZVW35) is based on the conventional third generation (ZVW30) with a 4.4-kWh lithium-ion battery that allows an all-electric range of 18 km (11 miles). A global demonstration program involving 600 pre-production test cars began in late 2009 and took place in Japan, Europe, Canada, China, Australia, New Zealand and the United States.

Prius Prime

The second generation Prius plug-in, called Toyota Prius Prime in the U.S. and Prius PHV in Japan, was developed in parallel with the standard fourth generation Prius model (XW50) released in December 2015. The model was released to retail customers in the U.S. in November 2016, followed by Japan in February 2017. In the American market, unlike the first generation model, the Prius Prime will be available in all 50 states. Cumulative global sales of both Prius plug-in generations totaled 79,300 units at the end of January 2017. The U.S. is the top selling market, with 46,133 units sold since inception through January 2017, of which, 3,788 units are second generation Prius Prime cars.

Prius v

At the January 2011 North American International Auto Show, Toyota revealed the 2012 model year Prius v, an extended hatchback wagon, which is derived from the third-generation Prius and features over 50 percent more interior cargo space than the original Prius design. US production ended in 2017.

Prius c

Toyota unveiled the Prius c concept at the January 2011 North American International Auto Show. The Prius c has a lower list price and is smaller than the previous Prius hatchback. The production version was unveiled at the 2011 Tokyo Motor Show as the Toyota Aqua, and was launched in Japan in December 2011. The Prius c was released in the US and Canada in March 2012, and in April 2012 in Australia and New Zealand. The Prius c is not available in Europe, where instead, Toyota is selling the Toyota Yaris Hybrid since June 2012. The Prius c and the Yaris Hybrid share the same powertrain.

Design and technology

The Prius is a power-split or series-parallel (full) hybrid, sometimes referred to as a combined hybrid, a vehicle that can be propelled by gasoline or electric power or both. Wind resistance is reduced by a drag coefficient of Cd=0.25 (0.29 for 2000 model) with a Kammback design to reduce air resistance. Lower rolling-resistance tires are used to reduce road friction. An electric water pump eliminates serpentine belts. In the US and Canada, a vacuum flask is used to store hot coolant when the vehicle is powered off for reuse so as to reduce warm-up time. The Prius engine makes use of the Atkinson cycle.

EV mode

When the vehicle is turned on with the “Power” button, it is ready to drive immediately with the electric motor. In the North American second generation Prius, electric pumps warm the engine by pumping previously saved hot engine coolant from a coolant thermos before the internal combustion engine is started. The delay between powering the car on and starting the internal combustion engine is a few seconds. The third generation Prius does not have a coolant thermos. Instead, the engine is heated by recapturing exhaust heat. A button labelled “EV” maintains Electric Vehicle mode after being powered on and under most low-load conditions at less than 25 mph (40 km/h). This permits driving with low noise and no fuel consumption for journeys under 0.5 miles (0.80 km), Longer journeys are possible as long as the speed is kept below 25 mph (40 km/h), acceleration is kept low and the battery has enough charge. The engine starts automatically when the battery starts to run low. Prior to the 2010 model, the North American model did not have the “EV” button, although one can be added to enable the “EV” mode supported internally by the Prius Hybrid Vehicle management computer. For the North American market, the third generation can remain in EV mode until 70 km/h (43 mph) depending on throttle and road gradient.

Environmental impact

Fuel economy and emissions in United States
Fuel economy and emissions in Japan

Fuel economy and emissions in United States

Since its introduction, the Toyota Prius has been among the best fuel economy vehicles available in the United States, and for the model year 2012, the Prius family has three models among the 10 most fuel-efficient cars sold in the country as rated by US Environmental Protection Agency (EPA). After the Honda Insight first generation was discontinued in September 2006, the Prius liftback became the most fuel-efficient car sold in the American market, until it was topped by the Chevrolet Volt in December 2010, as the plug-in hybrid was rated by EPA with an overall combined city/highway gasoline-electricity fuel economy of 60 mpg‑US (3.9 L/100 km; 72 mpg‑imp) equivalent (MPG-e). According to the EPA, for the model year 2012, and when only gasoline-powered vehicles are considered (excluding all-electric cars), the Prius c ranks as the most fuel-efficient compact car, the Prius liftback as the most fuel-efficient midsize car, and the Prius v as the most fuel-efficient midsize station wagon.

Fuel economy and emissions in Japan

The fuel economy performance and carbon emissions for all Prius family models sold in Japan since 1997. The ratings are presented for both, the older official 10-15 mode cycle test and the new JC08 test designed for Japan’s new standards that went into effect in 2015, but was already being used by several car manufacturers for new cars. The Prius 2nd generation became the first car to meet Japan’s new 2015 Fuel Economy Standards measured under the JC08 test.

References

Toyota Prius Website
Toyota Prius PHV Website
Toyota Prius Alpha Website