Most economical petrol cars

Increasingly under pressure to improve fuel efficiency and CO2 emissions across their model ranges, car manufacturers have accomplished some truly spectacular environmental feats in the last decade. The beauty is that doing your bit for the polar bears, and your wallet, needn't mean sacrificing comfort and style.

When the topic of squeezing more miles from every gallon is on the table diesel models always steal the limelight, but petrol models have also improved in leaps and bounds. And let's be honest, no oil burner can ever compete with a petrol unit as far as silky smooth and hushed operation is concerned.

To prove just how far manufacturers have come with petrol technology, we've picked the most economical and eco-friendly petrol model in 10 different market segments.

Green Car Guide

Top 10 most economical cars
Most economical cars in each class
Most economical used cars under £3,000
Most economical used cars under £5,000

City car: Fiat 500 0.9 TwinAir Dualogic - 70.6mpg - 92g/km

Fiat's trendy 500 has more in its locker than lovable retro looks. The TwinAir two-cylinder petrol engine is quite a piece of kit and points the way to the kind of economical petrol units we might be seeing more of in small cars very soon. With the Dualogic automatic gearbox it returns over 70mpg.

The 500 remains a fine small car with nimble driving characteristics and reasonable space for four passengers. Of course, the little Fiat is dripping in old-school design cues that hark back to the original 'cinquecento' of the 1950s.

Review: Fiat 500 TwinAir
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Supermini: Honda Jazz Hybrid - 62.8mpg - 104g/km

The Honda Jazz is the first supermini to employ a hybrid powertrain and just to be sure nobody was in any doubt that there's an electric motor in attendance, the hybrid version is called the Jazz Hybrid.

Petrol cars in the supermini class don't get any more economical than this but Honda insists it could have made the Jazz even greener. Instead, it went for a smaller battery pack, which preserved the boot capacity and the impressively versatile rear seats from the standard Jazz.

The sparkling fuel economy and emissions figures are backed up by reasonable performance. The 62mph barrier is breached in 12.3s and there's a 109mph top speed. Prices open at around £16,000.

Review: Honda Jazz Hybrid
Video: Honda Jazz Hybrid
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Family hatch: Toyota Auris Hybrid - 74.3mpg - 89g/km

On the outside this Auris may look identical to its lesser siblings, but under its bonnet beats the same Synergy Hybrid Drive as in the larger Toyota Prius - making it the first compact family hybrid to market.

Power comes courtesy of a 1.8-litre engine which, with some electrical assistance, develops a decent 98bhp.

The Auris' drive is relaxing and accomplished, though ultimately not as rewarding as that of the Ford Focus nor as refined as VW's Golf. On the plus side, its engine is smooth and hushed (more so than the standard Auris petrol mills), and thanks to CO2 emissions of 89g/km there's no forking out for road tax.

Review: Toyota Auris Hybrid
Review: Ford Focus ECOnetic
Review: Volkswagen Golf
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Large family: Toyota Prius - 72.4mpg - 89g/km

No list of the UK's greenest cars would be complete without including the Prius, which 13 years after its original launch, remains at the top of its segment. In its latest incarnation, launched in 2009, Toyota has squeezed its CO2 emissions and fuel economy harder still, with very impressive results.

In recent years the Prius has received more than its fair share of scepticism. But the hybrid still boasts the lowest CO2 emissions of any petrol car on the market. And for even lower emissions there's the plug-in version to look forward to.

Review: Toyota Prius
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Junior executive: BMW 318i - 44.8mpg - 146g/km

The BMW 3 Series is firmly established as the benchmark in the junior executive segment as far as handling and performance are concerned. In 318i format it also sets the standard for its competitors on fuel economy.

Powered by a 141bhp version of BMW's 2.0-litre engine this model is reasonably brisk too, dashing to 62mph in 9.1 seconds.

No competitor can rival the 3 Series for driver involvement. Its steering is precise with loads of feedback, its body beautifully controlled in corners and its suspension perfectly balanced between sporty and comfortable. Its ride is also refined and quiet, and the petrol engine silky smooth. A great all-round contender in short.

Review: BMW 3 Series
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Executive: Mercedes E200 CGI BlueEfficiency - 41.5mpg - 159g/km

To make this the most frugal petrol E-Class, the 200 CGI gets its power courtesy of a newly developed four-cylinder direct-injection engine 1.8-litre mill which develops a very healthy 181bhp. Yet, thanks to a standard start-stop function and several changes to optimise economy, it will trot an impressive 41.5 miles on every gallon.

It is also one of the cheapest E-Class models around, slipping neatly in under the £30k mark. Don't expect to feel short-changed though. The 200 CGI manages to retain everything we like about the E-Class, but now Mercedes-Benz manages to wrap all of that in a more eco-friendly and pleasantly affordable package.

Review: Mercedes E350 CGI BlueEfficiency
Review: Mercedes E-Class
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Luxury: Audi A8 3.0 TFSI - 31mpg (TBC) - 209g/km

Ingolstadt's new flagship seriously raised the benchmark for the luxury segment when it was launched in Miami towards the end of 2009. Filled to the gunwales with technological gadgetry from nightvision with pedestrian recognition ability, to a sat-nav that relies on Google Earth, this A8 gives a whole new meaning to 'Vorsprung durch Technik'.

Fortunately its oily bits are equally impressive. The 3.0 TFSI powertrain, which does service under the bonnet, is linked to a new eight-speed tiptronic gearbox and channels power to all four wheels. With fuel economy of 30mpg the new flagship isn't exactly thrifty, but it still easily trumps most rivals.

Review: Audi A8
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Coupé/Cabriolet: Honda CR-Z - 57mpg - 117g/km

Picking one model from a segment as broadly defined as coupés and cabriolets inevitably opens itself up to contention. Technically speaking the Smart Fortwo Cabrio (64mpg and 105g/km) is more frugal than the Honda, but it is just too much of a city car to be seriously considered by most buyers in this segment.

The latest Honda hybrid on the other hand makes for a cracking option - with head-snappingly striking styling, futuristic interior and sporty handling. Powered by a 122bhp 1.5-litre petrol-electric engine the CR-Z is keen but, requiring 9.9 seconds to 62mph, won't exactly be setting the road alight. Still, as an overall sporty hybrid, it suitably impresses.

Review: Honda CR-Z
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MPV - Toyota Verso-S 1.33 VVT-i Multidrive S - 54.3mpg - 120g/km

When the oddball Yaris Verso disappeared from the Toyota range it left a gap that has now been neatly plugged by the Verso-S. It's a mini-MPV that crams a lot of practical people carrier features into a compact package.

Crucially, it also benefits from Toyota's 1.33-litre Dual VVT-i petrol engine. It's a 98bhp unit that gives the car a reasonably brisk turn of pace coupled with very strong economy.

The manual model returns 51.4mpg but fit the Multidrive S CVT gearbox and that improves to 54.3mpg and 120g/km emissions. Prices for the auto models open at under £16,000.

Read a Toyota review
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4x4: Lexus RX450h - 44.8mpg - 148g/km

If you've always maintained that big 4x4s can't be thrifty then this Lexus turns that notion firmly on its head (even if it is the rare exception). Able to sprint to 62mph in just 7.8 seconds, it has plenty of shove too - yet it's less thirsty than a tiny Fiat Sedici (its closest green 4x4 rival) at the pumps.

Lexus models are renowned for their high levels of refinement, and this RX is no exception. It comes stacked with standard equipment to boot. Ok, it isn't the most engaging ride around and the body is prone to rolling in bends, but for a truly green full-size 4x4 it passes with flying colours.

Review: Lexus RX450h
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More from MSN Cars

Green Car Guide
Top 10 most economical cars
Most economical cars in each class
Most economical used cars under £3,000
Most economical used cars under £5,000
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How to save fuel - green driving tips

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