Technology: diesel combustion engine
On sale: now
Driven by: Alex Newby
What Car? deputy editor, and readers Jason Lewis, Will Slater and Chris Stallworthy
Our current Green Car of the Year doesn't use new-fangled batteries or hydrogen fuel-cells to achieve its impressive claimed 74.3mpg and 99g/km of CO2. No, the Volkswagen Golf 1.6 TDI 105 Bluemotion uses good old diesel power and proves that the internal combustion engine can rival some of the latest tech for green credentials.
It's all thanks to a few clever tricks and tweaks including an engine stop-start system, regenerative braking, more aerodynamic bodywork and low rolling-resistance tyres. In addition, longer gear ratios help the engine work as efficiently as possible, plus there's a gearshift indicator to help you choose the most efficient gear at any point.
What Car? entered a three-door Bluemotion in the RAC's Future Car Challenge, with a team of three What Car? readers and myself. So how did our readers rate their experience of driving the greenest Golf?
'The gears are really long, so you can't use second gear at low speeds as you normally would,' said Jason Lewis, 'That takes some getting used to. But it's incredible, really: even at 1000rpm the car wants you be in fifth gear – it's so focussed on being efficient.'
The only problem with the very slight delay in the engine restarting in Start Stop mode is if you're trying to pull out quickly at a junction.'
Will Slater liked the fact the Golf is still effectively an ordinary car with all of the usual attributes of an ordinary Golf.
'The ride on these low-rolling resistance tyres does seem a bit firm, but I like the fact you don't feel the Golf is a tree-hugging special. It's a normal car; it's comfortable and it's well made.'
Things got rather hot and steamy in the car, not just because taking part in the event was so exciting, but because they didn't use the air-con or open the windows in a bid to keep energy use and drag to a minimum.
The team also tried to eek the very most out of the Bluemotion by changing gear exactly when the car asked them to while keeping the revs as low as possible: 'Change too early and the engine labours and is clearly less efficient,' said Will.
'If you had to drive like this everyday to get the claimed fuel economy, it would be ridiculous,' Will continued. 'However, in terms of economy I think this technology is probably still the most real-world solution. Unless you keep your hybrid for ever, you'll never recover the cost of the energy to build it.'
The team were pleased with the 57mpg they achieved over the route. 'That may not sounds so impressive compared to the official figure of over 74mpg,' said Chris, 'but it's important that people bear in mind that 15-16 miles of the route was in dreadful traffic.'
The readers were really impressed with the whole Future Car Challenge, and were thrilled to have taken part. 'The event brings together manufacturers so they can challenge each other,' said Chris, 'and that can only be a good thing.'
Highlight of the day Our mpg – given that we spent half the journey stuck in heavy traffic through south London, the car's Start Stop system meant we didn't drop under the 57.8mpg we'd clocked up on the first 40 miles of the route.