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Toyota Prius proves a gas guzzler in a race with the BMW 520d
The Toyota hybrid is hailed as an eco-paragon, so how does it fare against a big BMW? To find out our correspondents go on a run to Geneva

The Prius, like the iPod, is more than a piece of clever technology. It symbolises something bigger – a responsible attitude, a healthier way of living. Toyota has sold more than a million examples of the car since launching it in 1997 and it has attracted a worldwide following led by Leonardo DiCaprio, Cameron Diaz and much of the rest of Hollywood.

It’s classified by the American government as the “most fuel-efficient car sold in the US” and this seal of official approval is reflected in a special status that the Prius and other hybrids enjoy over conventionally powered cars.

For example, you can drive a Prius in American “high occupancy vehicle lanes” – designed for vehicles carrying passengers – even if there’s nobody else in the car. In Britain the Prius has had a similar boost. You can enter the central London congestion zone without paying the usual £8-a-day charge. For road tax purposes it’s classed as an “alternative fuel vehicle” so you pay less tax than you would for a conventional car that produces the same emissions. Road tax is just £15 a year and in last Wednesday’s budget, Alistair Darling, the chancellor, renewed his commitment to preferential treatment for hybrids. Plus, if you drive a Prius as a company car it enjoys a 3% discount (until April) compared with the tax on other cars producing identical amounts of carbon dioxide.

But are transport and tax planners – here and in the US – being fair to the people who drive conventional cars? The official fuel consumption figure for the Prius – supplied by Toyota itself – is 65.7mpg in mixed motoring. That’s a claim not supported by many of the letter writers to The Sunday Times who say they get nearer to 50mpg. If our readers are right and the official figure is wrong it has important implications, not least of which is that people driving frugal diesels are getting a raw deal.

To find out we set a challenge: to drive a Prius to Geneva using motorways and town driving. The direct route is 460 miles but we drove almost 100 miles further to give the Prius the advantage of running in urban conditions where its petrol-electric drivetrain comes into its own.

We took along a conventionally powered car – a diesel BMW executive saloon – for comparison and drove both cars an identical number of miles (545).

BMW 520d: driven by Nicholas Rufford

The BMW doesn’t have the external look of a green car and you don’t get the same self-righteous glow when you are driving it. There’s no hybrid badge on the back; in fact, because it’s the entry level car of the 5-series many buyers opt for “badge delete” so they don’t show other motorists they went for the cheapest option at £27,190.

But it does have a few tricks up its sleeve to conserve fuel. Efficient Dynamics, as BMW refers to its fuel-saving technology, is a term coined by Bavarian marketing men for refinements that taken on their own are nothing spectacular but together improve fuel economy. Rather than Toyota’s big idea – a radically different system of powering a car using a petrol-electric drivetrain – BMW has sunk its research effort into lots of less radical things.

The most important of these is the new four-cylinder engine. It’s available in the 3-series but here it’s perfectly at home in the bigger 5-series saloon where it generates a surprising 177bhp. Surprising because it’s only 1995cc and it sips fuel. Combined fuel consumption is – officially – 55.4mpg and emissions are 136g/km, which puts it into tax band C. That’s respectable for its size, especially when you consider that 13 cabinet ministers are driven in cars with tax band F – the second highest bracket – and one, we don’t know who, has a band G car.

Various other features of the new BMW contribute to its frugality. It’s got better aerodynamics to reduce drag; low rolling resistance tyres; and a dashboard gauge that gives you a continuous fuel consumption readout so you know when to change gear.

So how does it drive? Well, much like any other executive saloon, actually. Its six-speed manual transmission needs quite a lot of work but if you are concerned about fuel economy then it’s a small price to pay for the extra 5mpg that it gains over the automatic version.

The 520d is not startlingly quick, but it will reach 62mph in 8.3sec. As for the claimed top speed of 144mph, I didn’t get the chance to test it to its limit but I think it would have struggled to reach that. Nonetheless, it cruised happily at the French autoroute limit (dry conditions) of 78mph towards the champagne region.

As I did so, I noted with slight satisfaction that Jason was having difficulty keeping up, so I cut my speed. Had I been really serious about saving fuel I could have also switched off the air-conditioning and the stereo but I was more concerned about making this a real-world test.

Stuck in rush-hour traffic in Reims, fuel consumption dropped to an average of about 40mpg – still not bad when you consider the size of the car. BMW has fitted a diesel particulate filter, enabling the car to meet ever more stringent European Union limits on emissions. Another feature designed to cut running costs is the brake regenerative system – similar to that in the Prius – which recovers energy from braking to recharge the battery and help power the electrical systems. To what extent this is a genuinely eco-friendly feature and how much a conscience salver is impossible to tell when you’re driving.

But you can’t argue with the end result. Approaching Switzerland I felt confident of beating Jason. The computer was telling me that, for the journey as a whole, I had averaged more than 50mpg. The test had taken us along just over 200 miles of autoroute, about 200 miles of B roads, including winding ascents and descents in Switzerland, and 100 miles of urban driving.

Before we set off, Jason and I filled our tanks to the brim. At the end of the journey, at a filling station in Geneva, we filled them again to find out how much fuel we’d used. The BMW had done the journey on 49 litres (just over two-thirds of a 70-litre tank). Jason had . . . well, I’ll let him tell his own story.

Toyota Prius: driven by Jason Dawe

The Prius is not a car you can easily get excited about, at least on a purely visual basis. But this test was not about kerb appeal, it was about pump avoidance. The Prius was designed with a straightforward goal in mind – to create a five-seat family hatchback that was as good on fuel as a 2+2 supermini. Straightforward aims are often notoriously difficult to achieve.

Toyota’s big idea was to use hybrid power. In other words, two forms of propulsion. The bulk of that power comes from a 1.5 litre petrol engine producing just 77bhp. That kind of power may be able to keep the Prius cruising along but is hardly enough to ensure decent acceleration. So added to that comes a battery-powered electric motor generating the equivalent of a further 67bhp and a thumping great 295 lb ft of torque.

There’s no need to plug the Prius into an electric socket to keep the batteries topped up as this is done every time the car brakes, and there is trickle charging by the petrol engine while driving normally. The result of lumping together these two sources of power is a car that can reach 62mph from standstill in less than 11sec and reach 106mph flat out, hardly dragstrip quick and slower than the BMW, but still respectable.

Toyota was obsessive about saving weight in the Prius; at just 2,921lb it is 573lb lighter than the BMW 520d, surely a factor that will pay dividends at the pumps.

Clever power and a light kerb weight stand the Prius in good stead but it’s the car’s incredibly low drag coefficient that may just tip the scales in my favour when it comes to long motorway stretches at higher speeds. As slippery as a campaign manager discussing political donations, the Prius should take less energy than the BMW to maintain a constant cruising speed.

No sooner had we left the offices of The Sunday Times in London than my eyes locked limpet-like on the trip computer readout that tells you how many mpg you are achieving. This was to become my obsession over the next 545 miles as I battled to nudge the Prius into performing somewhere close to Toyota’s claim of 65mpg-plus motoring.

By the time we reached the Channel tunnel the display revealed that I had averaged 55mpg. Hopefully things would improve on the long, uninterrupted roads in France. They didn’t – despite the fact that I didn’t use the air-conditioning and avoided turning on the stereo in an effort to conserve power.

To break the boredom of constantly looking at the trip computer I pressed the throttle into the carpet for a few seconds, but seeing the fuel consumption suddenly dip to less than 10mpg I backed off. When we stopped in Reims neither Nick nor I was willing to declare our average fuel economy figures. I interpreted his reticence as a sign of my upcoming victory.

The next day it became clear my Prius did not like motorways, at least not at 75mph into a headwind. My trip meter informed me I was now averaging about 45mpg; the Prius was not going to make it to Geneva on just one tank.

I took the precaution of buying a 10-litre can and filling it with petrol. Sure enough, the dashboard soon informed me the fuel tank was empty, the petrol engine stopped and for two surreal miles I coasted along on battery power. Only when I approached a long steep uphill stretch did I finally drift to a halt. As I filled the tank I consoled myself with my last chocolate bar.

Coasting down the mountain into Geneva my Prius averaged 99.9mpg for a full 10 minutes. It was the highlight of my journey and improved my overall average fuel economy by a full 2mpg. But it was not enough. For all my defensive driving, slippery bodywork and hybrid technology, my average fuel consumption was 48.1mpg. I’d lost to a Beemer and I was disappointed; I had never driven so slowly or carefully for so long in my life. I’m considering buying a V8 Range Rover and opening my own oil well in protest.

Vital Statistics

Model BMW 520d SE
Engine 1995cc, four cylinders
Power 177bhp @ 4000rpm
Torque 258 lb ft @ 1750rpm
Transmission Six-speed manual
Official fuel/CO2 55.4mpg / 136g/km
Performance 0-62mph: 8.3sec
Top speed 144mph
Road tax band C (£115)
Price £27,190
Fuel used on test 10.84 gallons (50.3mpg)
Fuel cost £54.19 (diesel)
Model Toyota Prius T Spirit
Engine 1497cc, four cylinders
Electric motor 50kW/67bhp
Power 77bhp @ 5000rpm
Torque 295 lb ft (motor) 85 lb ft (engine)
Transmission CVT automatic
Official fuel/CO2 65.7mpg / 104g/km
Performance 0-62mph: 10.9sec
Top speed 106mph
Road tax band B (£15, alternative fuel)
Price £20,677
Fuel used on test 11.34 gallons (48.1mpg)
Fuel cost £54.64 (petrol)

If you don't use the brakes on the Prius its just a normal car.

Be interesting to see comparions of round town driving, but I bet they won't do that.

If you don't use the brakes on the Prius its just a normal car.

Be interesting to see comparions of round town driving, but I bet they won't do that.

If you don't use the brakes on the Prius its just a normal car.

Be interesting to see comparions of round town driving, but I bet they won't do that.

I agree that in heavy enough traffic, the Prius would clearly be better than the Beamer - as would a moped. So what's your point? If you pick a specific enough set of conditions, you'd probably find an old V12 Jag was better than a Prius!

If you don't use the brakes on the Prius its just a normal car.

Be interesting to see comparions of round town driving, but I bet they won't do that.

My Puglet 106 deezil is 12 years old and just passed it's MOT again. I don't hang around but still manage to get around 55 mpg.
My point here is that for a Pious to be as eco friendly as claimed (its total enviromental debt including manufacture and disposal) every one will have to last 16 years. I really cannot see ANYONE buying one of these and keeping it for 16 years.
I guess there's the second hand market, but as a vehicles condition deteriorates and these probably being largely too complex for the home mechanic I just can't for the life of me see there being more than a small handful surviving that long.
A future "Practical Classic"? I think not.

There must be loads of servicable cars scrapped not because they are beyond repair, but because the new CAT costs the same as a newer car.

It would be more usefull (if I gave a damn anymore) to know the whole life enviromental cost of the car. I would like a new car, doing 60 to the gallon would be nice too, but my nearly 10 year old car just needs a service. It won't get 60mpg ever, but surely it's better to keep maintaining and running the old one that buying a new one?

According to which, the prius produces more pollution per mile than a hummer.

You mean the study that assumed a Prius would be thrown away after 100,000 miles, whereas a Hummer would be thrown away after 300,000 miles (and other studies that make equally ridiculous assertions to "prove" their proint)?

http://tinyurl.com/2ceykh

(edit, oops, sorry mole, didn't see your post before I responded)

By Chris Demorro

The Toyota Prius has become the flagship car for those in our society so environmentally conscious that they are willing to spend a premium to show the world how much they care. Unfortunately for them, their ultimate ‘green car’ is the source of some of the worst pollution in North America; it takes more combined energy per Prius to produce than a Hummer.
Before we delve into the seedy underworld of hybrids, you must first understand how a hybrid works. For this, we will use the most popular hybrid on the market, the Toyota Prius.

The Prius is powered by not one, but two engines: a standard 76 horsepower, 1.5-liter gas engine found in most cars today and a battery- powered engine that deals out 67 horsepower and a whooping 295ft/lbs of torque, below 2000 revolutions per minute. Essentially, the Toyota Synergy Drive system, as it is so called, propels the car from a dead stop to up to 30mph. This is where the largest percent of gas is consumed. As any physics major can tell you, it takes more energy to get an object moving than to keep it moving. The battery is recharged through the braking system, as well as when the gasoline engine takes over anywhere north of 30mph. It seems like a great energy efficient and environmentally sound car, right?

You would be right if you went by the old government EPA estimates, which netted the Prius an incredible 60 miles per gallon in the city and 51 miles per gallon on the highway. Unfortunately for Toyota, the government realized how unrealistic their EPA tests were, which consisted of highway speeds limited to 55mph and acceleration of only 3.3 mph per second. The new tests which affect all 2008 models give a much more realistic rating with highway speeds of 80mph and acceleration of 8mph per second. This has dropped the Prius’s EPA down by 25 percent to an average of 45mpg. This now puts the Toyota within spitting distance of cars like the Chevy Aveo, which costs less then half what the Prius costs.

However, if that was the only issue with the Prius, I wouldn’t be writing this article. It gets much worse.

Building a Toyota Prius causes more environmental damage than a Hummer that is on the road for three times longer than a Prius. As already noted, the Prius is partly driven by a battery which contains nickel. The nickel is mined and smelted at a plant in Sudbury, Ontario. This plant has caused so much environmental damage to the surrounding environment that NASA has used the ‘dead zone’ around the plant to test moon rovers. The area around the plant is devoid of any life for miles.

The plant is the source of all the nickel found in a Prius’ battery and Toyota purchases 1,000 tons annually. Dubbed the Superstack, the plague-factory has spread sulfur dioxide across northern Ontario, becoming every environmentalist’s nightmare.

“The acid rain around Sudbury was so bad it destroyed all the plants and the soil slid down off the hillside,” said Canadian Greenpeace energy-coordinator David Martin during an interview with Mail, a British-based newspaper.

All of this would be bad enough in and of itself; however, the journey to make a hybrid doesn’t end there. The nickel produced by this disastrous plant is shipped via massive container ship to the largest nickel refinery in Europe. From there, the nickel hops over to China to produce ‘nickel foam.’ From there, it goes to Japan. Finally, the completed batteries are shipped to the United States, finalizing the around-the-world trip required to produce a single Prius battery. Are these not sounding less and less like environmentally sound cars and more like a farce?

Wait, I haven’t even got to the best part yet.

When you pool together all the combined energy it takes to drive and build a Toyota Prius, the flagship car of energy fanatics, it takes almost 50 percent more energy than a Hummer - the Prius’s arch nemesis.

Through a study by CNW Marketing called “Dust to Dust,” the total combined energy is taken from all the electrical, fuel, transportation, materials (metal, plastic, etc) and hundreds of other factors over the expected lifetime of a vehicle. The Prius costs an average of $3.25 per mile driven over a lifetime of 100,000 miles - the expected lifespan of the Hybrid.

The Hummer, on the other hand, costs a more fiscal $1.95 per mile to put on the road over an expected lifetime of 300,000 miles. That means the Hummer will last three times longer than a Prius and use less combined energy doing it.

So, if you are really an environmentalist - ditch the Prius. Instead, buy one of the most economical cars available - a Toyota Scion xB. The Scion only costs a paltry $0.48 per mile to put on the road. If you are still obsessed over gas mileage - buy a Chevy Aveo and fix that lead foot.

One last fun fact for you: it takes five years to offset the premium price of a Prius. Meaning, you have to wait 60 months to save any money over a non-hybrid car because of lower gas expenses.

2) I can plug it in