Car that runs on air: Peugeot 2008 Hybrid Air prototype review

The Peugeot 2008 Hybrid Air prototype is the first fully-functioning showcase for PSA’s compressed air hybrid technology. It’s the French answer to BMW’s electric iCars, and Audi’s plug-in hybrid e-tron range, and makes a small crossover like the 2008 capable of an impressive 97.4mpg and 69g/km, without the need for a heavy and expensive battery pack.

Central to the HYbrid Air's powertrain is a compressed air tank, entirely self contained, which can hold 20 litres of nitrogen and oil at a pressure of 220 bar. By discharging this tank and forcing the oil through a hydraulically actuated motor which spins the front wheels.

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Why go to all that trouble? PSA ultimate target is to make a 2.0l/100km (141mpg) car a realistic and affordable showroom possibility, and reduce average CO2 emissions for its entire range to 116g/km by 2015 – and this Hybrid Air technology is seen as a crucial way to achieving that.

Our test drive took place right in the heart of Paris behind the wheel of a 2008, but whether the system makes it to production in this model or a Citroen C3 (the model in which the technology was first shown) is yet to be decided. Emerging into the French capital's notoriously anarchic hustle and bustle, the automatic test mule crossover glides serenely in the zero emissions mode offered by air-only power. As per any hybrid car you’ve driven, the system works in purely electric mode until either the ‘charge’ (or in this case, air) is depleted, or when more acceleration is demanded.

The Hybrid Air system can operate in zero emissions air mode, petrol-engine-only mode, or petrol and air in combination. Driven carefully, it takes about 500 metres for the tech to exhaust itself around town, and the 81bhp 1.2-litre turbocharged three-cylinder petrol engine kicks in with a gruff low growl to help push things along. It's a momentary boost, as fully recharging takes no more than ten seconds at city speeds, and despite the apparently short range the centre display still claimed 60 per cent of our journey was emissions free.

The recharging is done by a ‘hydronic’ pump that recirculates oil back into the main tank, not just when the petrol engine is on, but when you come off the throttle and hit the brakes, too. In that respect it’s similar to a battery hybrid’s regenerative braking system.

Threading the car down narrow Parisian streets and wide main roads exposes a few flaws though: It’s sluggish off the line compared to an EV hybrid, and there's lack of power assistance to the steering, which feels heavy at lower speeds, although that’s something PSA’s engineers can work on recalibrating.  

It’s also tricky to stay in zero emission mode as even small squeezes of the throttle cause the engine to fire up, a result of the longer gearing designed to keep emissions down. This 2008's prototype status has to be taken into account, and the congested city streets meant we couldn’t use all of the claimed 121bhp and 200Nm of torque, but even so – boosting the performance is an area that needs improvement.

At the moment, comfort is the name of the game and the powertrain at its best when cruising. The ride was suitably refined, too, soaking up the Parisian cobbles and bumps with minimal fuss. It helps that the compressed air set-up is lighter than the equivalent battery-powered hybrid technology, and Peugeot-Citroen's efficiency drive is backed up by a more environmentally-friendly manufacturing and recycling process.

On the road running costs obviously benefit as well, with a claimed 97.4mpg average whilst emitting just 69g/km. In comparison, a regular Peugeot 2008 1.2 automatic manages 65.7mpg and 99g/km.

Best of all though, engineers claim it's cheaper to produce, and therefore hope to pass these savings on to customers. A production model is a few years away yet, but when it does arrive expect a similar price mark up over standard petrol models as for an automatic diesel variant. If it makes it's way to the recently launched C4 Cactus then, prices could start from around £17,000.

At a glance

Price: from £17,000 (est)
Engine: 1.2-litre 3cyl turbo, plus hydraulic motor
Power/torque: 121bhp/200Nm
Transmission: Planetary gearbox, front-wheel drive
0-62mph: N/A
Top speed: N/A
Economy: 97.4mpg
CO2: 69g/km
On sale: 2017

Microsoft Surface Pro 3 Now Available: Here's What You Need to Know

Microsoft's latest tablet/laptop hybrid, the Surface Pro 3, today becomes available in the U.S. and Canada.

The Windows 8.1 machine has a 12-inch, 2,160x1,440 pixel touchscreen screen powered by an Intel graphics chip, and two (front and rear) 5-megapixel cameras.

It comes with three processor flavors, all of them Intel dual-core chips: a 1.5GHz i3, a 2.9GHz i5 or a 3.3GHz i7. It has either 4 or 8GB of RAM, 64/128/256/512GB of storage, and is priced from $799 to $1949.

Bluetooth, Wi-Fi, USB 3.0, and a Mini DisplayPort are all on board. Finally, the device weighs only 800g and measures 11.5x7.93x0.36 inches.

We've taken an in-depth look at the new Surface Pro 3 and found it to be the most complete Surface device ever.

Here's a couple of other highlights about the device which you might find interesting.

This is how it compares to the MacBook Air, and here are our thoughts on whether the device could be a laptop killer.

Microsoft has released a software update right before the launch; the company reps tell us it brings better performance and some minor bug fixes.

You can order the Surface Pro 3 from Microsoft's online store or Best Buy. The shipping date is June 30, and only the i5 versions (with 128GB and 256GB of storage) are currently available. Other variants can be pre-ordered, but they will ship by August 1, 2014.

Is the Toyota Prius a safe car or is the accelerator problem too risky?

The Prius is safe. The accelerator problem was a problem that didn't happen on the Prius. It happened on some models of GMs, Fords, and Toyotas made in the U.S. that used the CTS pedal. The metal used in this pedal would deform after a few years and cause sticking. All three manufacturers had recalls for this, but only Toyota made the media. The Prius never used this pedal. 

There was also the problem with the floor mat being jammed in the pedal. Although Toyota had the dealer modify the pedal to reduce the potential for jamming, the Prius has brake-override so that if you pressed firmly on the brake (even with the accelerator jammed) the brake would override the accelerator. In addition, the main cause of floor mat pedal jamming was the addition of a second mat over the factory mat. But really, floor mats, bottles, and other assorted items have been causing car pedals to jam since there have been cars. Note that not all Toyotas (including the rental Lexus that the CHP officer and his family lost their lives in) have brake override. 

The Prius is one of the safest cars out there, and here's why: 

1. There are four braking systems on the Prius: 

- Regenerative brakes 
- Friction brakes 
- Engine brakes 
- Parking brakes 

2. Vehicle stability control: 

- A system that prevents doughnuts during slippery conditions if you are going anything like a reasonable speed. Studies from Europe and Japan indicate that VSC reduces head-on collisions by over 30%. Other cars have this feature, but not in the Prius' price range. 

4. Brake assist: 

- A system that applies extra force to the brake pedal when it senses an emergency stop. Studies by Mercedes indicate that people press the brakes quickly but not hard enough. Brake assist compensates for this tendency. 

5. Brake override: 

- A system that stops the acceleration when the brake pedal is pressed firmly. 

6. The smooth acceleration of the Prius (there are no gears that shift) helps prevent you rear-ending someone if they slow down right after stopping. (An old fashioned economy car typically has a very low first gear to disguise the fact the engine is small--this creates rapid acceleration up to about 10 mph after which the acceleration bogs down. The Prius smoothly accelerates up to it's maximum speed of about 105 mph which is controlled by the system.) 

7. Optionally in the 2010 Prius: 

- Radar pre-collision 

- Lane keep 

Many of these systems prevent the accident in the first place. The best accident is one you don't have. 

Oh, and don't worry about the battery. The 2004+ Prius batteries are likely to last as long as the car.