Driving the Citroen C4 BioFlex

Introduction

Fuel you can grow. Sounds too good to be true doesn't it? Well it's happening, and manufacturers are increasingly able to offer cars to run on new bio-fuels. Citroen's C4 BioFlex is such a car, and it'll be coming to the UK soon.

What is it?

Put simply it's a Citroen C4 that can run on bio-ethanol or conventional unleaded petrol or even a combination of both. The fuel the C4 BioFlex runs on is an ethanol/petrol mix - up to 85% ethanol, often referred to as E85. Other grades are available, and the C4 BioFlex is also able to run on these, as it is on conventional unleaded petrol. When using E85 the fuel consumption actually increases, but, and here's the green bit, as E85 is a plant-derived alcohol fuel, the CO₂ emissions are less. Not much on paper admittedly, down from 169g/km to 160g/km. However, measured on a so-called 'field to wheel' basis emissions are reduced by 40% through the CO₂ absorption process when the fuel is actually being grown.

How does it drive?

Exactly the same as a conventional C4 1.6-litre petrol. Really, there's absolutely no difference behind the wheel. The numbers suggest that on E85 the C4 BioFlex is actually a tiny bit faster to 62mph than its conventional petrol alternative, but few will be able to notice the 0.4 second difference the greener fuel makes. The 1.6-litre engine is a willing and refined unit and the C4 itself drives nicely enough. It's not quite as sharp to drive as Ford's Focus, which is also offered in a similar bio-ethanol compatible guise badged FlexiFuel, but it's a green car that offers few compromises for its environmental credentials. After all, it's just a regular car, which happens to run on a more environmentally friendly fuel.

Planet hugger or planet mugger?

Flex fuel vehicles are a stepping stone to alternative fuels. Their ability to run on regular fuel as well as E85 bio-ethanol is beneficial to early adopters as fuel stations with E85 are presently very limited. Indeed, there are only around 19 outlets in the UK stocking pure E85, mostly located in Morrison's supermarkets. The green credentials don't actually look that impressive on paper; after all when running on E85 the C4 is actually thirstier than it is on conventional petrol. However, the fuel is cheaper, or at least it should be, and emissions are lower.

But the real measure is that field to wheel one, where the actual growing of the fuel is added to the emissions calculation. Unlike emissions from conventional fossil fuels, which only ever produce CO₂, bio-fuels absorb the gas when the raw products used to create them are growing. Bio-fuels might soon be produced from waste products too, making it an even more environmentally friendly option. There are some who argue that the agriculture to grow the crops to produce bio-ethanol is very CO₂ intensive itself, but whatever way it's looked at flex fuel vehicles like the C4 BioFlex are a step in the right direction.

Verdict

Many think that buying a greener car means that they have to make sacrifices. That's not the case with cars like the C4 BioFlex. If it wasn't for the badge on the bootlid it could be mistaken for a regular C4. There are no additional fuel tanks, batteries or plugs required, as it's just a regular car that can take advantage of E85 fuel when it's available. And that's currently the biggest drawback; fuel availability. There simply aren't enough E85 pumps in the UK to really make a difference. So unless you live near one, or drive regularly on the continent where E85 is more widely available, it might not be worth having. However, and Citroen's yet to confirm UK prices, if it's no more expensive than a standard car then it's worth considering. Especially as E85 pumps are only likely to become more common in time.