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Why I Drive a Prius or 61 miles per gallon feels good

Toyota Prius 120 mpg at 56 miles per hour

The Prius is a fun, comfortable car with the highest gas mileage

Toyota Prius 61 mpg at 56 miles per hour

We bought the Prius three years ago because it was a fun gizmo car that promised high gas mileage.

40,000 miles later the car has not disappointed.

I tested the gas mileage this week on a trip to Halifax and the top mileage was 61 miles per gallon, or 3.8 liters per 100 kilometers.

All the fuel efficiency in this story is US gallons. The fuel efficiency is restated in Canadian values at the end.

The popular Prius

The Prius was first sold in 1997 and has reached the 2.5 millionth car sold in February of 2012. You see them everywhere, especially if you own one.

It’s like being in the 1950s and discovering the Volkswagen Beetle. Prius owners are almost a club.

In 2009, there was only one Prius with 3 trim levels. Today there is a Prius C for “city”, a Prius V for “volume” as in station wagon, and the Prius Plug-In.

Our base 2009 Prius (2nd Generation) fits 5 adults comfortably and doesn’t bottom when loaded. The rear hatch has plenty of room, including space for my wheelchair. We pack it full for trips and have a great time on the road.

Winter driving versus summer driving

During the winter, fuel economy had dipped to 38 mpg with winter tires and mostly highway driving. That’s still a respectable but less than the official fuel efficiency of 45 mpg.

I wanted to see if things got better with new summer tires, wheel alignment and oil change. After trying to purchase Michelin Energy Saver AS, I settled on the more comfortable Goodyear Assurance ComforTread, which TireTack rated as 7% less fuel-efficient. Michelin inexplicably had no Energy Saver AS tires available until August.

The ComforTread are significantly quieter and smoother than the winter tires and the fuel efficiency jumped immediately. Driving around Halifax for three days, the mileage went up to 44 mpg.

Fuel efficiency depends on speed and acceleration rate

3rd Generation Prius economy versus speed (chart by TigerFrank on Prius Chat)

The Prius is a hybrid system that uses batteries and electric motors at low-speed and then a 1.5 liter gasoline engine.

Toyota have more than 10,000 patented innovations to squeeze the efficiency, and tweak the emissions and safety of this car.

At low speeds, the electric motors are doing the heavy lifting. As the chart shows, the Prius will get as high as 100 mpg (2010 models onward) at low speeds. As the car is driven faster, mileage drops.

Illustration - wikipedia

I found in the 2009 the top cruising mileage at 55 miles per hour is 61 mpg. When I held a steady speed of 63 miles per hour, the fuel efficiency dropped to 47 mpg. Both of those numbers are on cruise control, through a variety of climbing and descending hilly terrain and use the on board computer.

Driving without cruise control through speed zones of 40 to 55 miles per hour wasn’t that much worse, 57 miles per hour.

If you want to race from stop signs and traffic lights, pass every car on the highway and cruise at 75 miles per hour the Prius is probably not your car.

However, if you like to feel smart and green about the environment, the Prius delivers 40 to 60 miles per gallon with low emissions,  in a safe and comfortable vehicle.

Vehicle emissions

It also feels good to help with pollution of our planet. The Prius is a smart car and has low emissions.

“The second generation Prius tied with the MINI Cooper D as the fourth least CO2-emitting vehicles at 104 g/km, behind the Ford Fiesta Econetic at 98 g/km and the tied Volkswagen Polo 1.4 TDI/SEAT Ibiza 1.4 TDI at 99 g/km – it is the least CO2-emitting gasoline powered car, since the Ford and the Polo/Ibiza (both of which are city cars) run on diesel. Wikipedia

The newer 3rd Generation Prius models meet the stringent California standards emitting 70% less than the average car sold in the US. “The new Prius is certified as a Super Ultra Low Emission Vehicle (SULEV) and an Advanced Technology Partial Zero Emissions Vehicle (AT-PZEV) in California, as well as those states adopting California emission standards.”

Safety

The Prius is rated safe or reasonable. I like the fact that it comes with side air bags as standard. The car tracks well on wet or snowy roads. Of course, defensive driving is the best way to stay safe on the road.

The backup camera helps but it does keep you busy checking mirrors, screen and scanning behind when backing up.

If there is anything the car needs is longer vision headlights. Like most cars, at 60 miles per hour at night, we are driving beyond our ability to see and respond to emergencies. Last winter we traveled through New Brunswick at night where moose pose a deadly threat to drivers. This week we saw deer on the edge of the highway at dusk.

Other Models

The Prius C has city efficiency ratings of 53 mpg which is better than the Prius 3rd Generation at 51 mpg. The Prius V is rated 44 mpg city driving. If you want the ultimate, the Prius Plug-In gets 95 mpg city driving.

The Plug-In is not that much better on the highway at 50 mpg. Next is the Prius 3rd Gen at 48 mpg, followed by the Prius C at 46 mpg and Prius V at 40 mpg.

Canadian efficiency

Canadian gallons are 5/4ths of the US gallon. Our miles aren’t any longer but it’s all officially Klicks (km) in Canada. US service personnel get that foreign assignment feeling driving in Canada.

Prius fuel efficiency in Canadian numbers are:

Around town – 46 mpg

Highway – steady 90 km/h – 75 mpg

Highway – steady 100 km/h – 57 mpg

Highway – speed zones 70 to 100 km/h – 70 mpg

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