If you want a warm fuzzy feeling that's not caused by climate change, buy one of these. By Thomas Falkiner When it comes to drawing up lists of frugal automobiles, many websites and publications will feature cars that they haven't driven. They'll simply choose their selection by looking at the ridiculously low claimed fuel-consumption figures: numbers that have been achieved by manufacturers in conditions so far removed from our everyday reality that they are totally irrelevant. So I'm putting my money where my mouth is here, by sharing with you the six most fuel-thrifty machines I have ever tested.THE SUMMIT SUPERCAR: BMW i8: R1.79-millionThe BMW i8 has to be one of the coolest supercars on the planet. Built by aliens and teleported from the future, it turns heads and piques human curiosity like no other. While those outrageous scissor-doors and carbon-fibre-reinforced body panels steal the show, it's the i8's unique powertrain that makes the deepest and most lasting impression.Essentially a plug-in hybrid, this BMW has an electric motor twisting the front wheels and a ridiculously over-endowed three-cylinder turbo engine driving the rears. When their muscle combines you get a machine that can keep up with most comparable Aston Martin, Lamborghini and Porsche models. Drive it sensibly though and the i8 will return real-world fuel economy figures these manufacturers can only dream of.Used as a daily drive I averaged a Corolla-rivalling 7.8l/100km - in a car that can sprint to 100km/h in only 4.4 seconds. Insane. You can also glide along silently in all-electric eDrive mode for up to 35km - enough for the daily home-office-home commute that most of us make. This means you could, theoretically, pilot a supercar from Monday to Friday without burning a single drop of petrol. If you do, you're looking at a laughable (claimed) CO2 figure of just 49g/km.full_story_image_hleft1LEFT-FIELD HATCHBACK: Honda CR-Z: R384 100The Honda CR-Z generally gets a bad rap. Probably because those exciting looks write cheques the mild hybrid drivetrain cannot cash. The spiritual successor to the darling-of-the-1980s CRX is a lukewarm performer at best. Look beyond this, however, and you will discover a well-built, fun-in-the-corners hatch that is easy to live with and a pleasure to own. I should know - I drove one for a year. While it's relatively heavy on carbon dioxide (124g/km), it can deliver impressive frugality. I once did 754km on a tank at 5.4l/100km - just 0.2l more than what Honda claims for it.full_story_image_hleft2A SWEDE EXECUTIVE:Volvo V60 D4: R492 500This often-overlooked estate is, believe it or not, the most fuel-efficient vehicle I have ever piloted. Period. Which is strange because the V60 is a hefty machine with a large boot and seating for five. The secret lies inside its brilliant Drive-E engine that sips diesel like a poor whisky aficionado sips a tot of 50-year-old Glenfiddich single malt. After blipping the Eco+ button on the dashboard I drove from Joburg to Durban and back on just over half a tank of the devil's oil. That's an average of 4.6l/100km. CO2? You're looking at 109g/km. Get the booted S60 D4 if wagons aren't your thing.full_story_image_hleft3SOCCER MOM'S TAXI:Nissan Qashqai 1.5 dCi Acenta: R338 800The sharp-looking Nissan Qashqai is a vehicle that checks all boxes and then some. It's practical, well-priced, comfortable and - for an SUV - surprisingly good to drive. In fact it remains the default answer to that question I get asked all the time: what new car should I buy? Although there are many engines to pick from, the one you want is the 1.5-litre diesel with the manual gearbox. For after the Volvo V60 D4 it remains the second-most efficient car I've steered through the streets. The figures don't lie: 623km, 34-litres of juice - 5.4l/100km. CO2 is a reasonable 109g/km.full_story_image_hleft4ELECTRIC WARRIOR: BMW i3 REX: R602 500If you're a South African in the market for an electric vehicle - or EV for short - you basically have two choices: Nissan Leaf or BMW i3. The Leaf is more affordable while the i3 is quicker and, let's face it, a whole lot more exciting to look at. Both are good to drive, although the BMW just feels that much more engaging. It's also the more interesting place in which to spend time. A minimalist design approach makes use of sustainable materials like kenaf fibre, recycled bottles and eucalyptus wood which develops a unique patina over time.But where the i3 really triumphs over the Leaf is in alleviating range-anxiety. The range-extender version gets a small two-cylinder petrol engine that automatically turns on to recharge the battery when it gets low on juice. This gives you, in real-world driving conditions, an effective range of around 240km. With the range-extender doing its thing, CO2 emissions weigh in at an incredible 13g/km.full_story_image_hleft5ENTRY-LEVEL UPSTART: Volkswagen Up!: R137 600The Up! arrived in February to play hardball with the rest of the Betty Budget motoring pack. Oozing a Bauhaus design aesthetic, this quality piece of kit feels more premium than its price-tag suggests. The three-cylinder engine might not be a purveyor of speedy thrills, but - having to haul just 929kg - it does offer impressive fuel-economy and 108g/km of CO2. In the stop-start urban milieu I was cracking just over 6l/100km. Drive with more consideration and you should easily dip down into the fives - better than many of the dearer turbocharged offerings in the class above it...