What makes a car green?

As green increasingly becomes the colour of choice for car buyers, Mike Gerber looks into what makes a car more sustainable and analyses the latest innovations likely to hit the roads in the UK


Growing demand from consumers for ethical products, and legislative and fiscal carrot-and-stick measures, are driving the green-car market. New cars are now sold with banded efficiency labels, like fridges. They must also comply with increasingly tight European emission standards.

Cars are taxed based on how much CO2 is emitted. Company cars are subject to Benefit in Kind tax calculated as a percentage of CO2 emissions. From late October, Transport for London will exempt vehicles emitting up to 120g/km CO2 from the congestion charge, whereas owners of vehicles emitting more than 225g/km will be charged £25 a day.

By 2010, first-year road tax for cars emitting more than 225g/km will be £950; those emitting no more than 130g/km will be granted a 12-month exemption.

So, what is a green car? There are the alternative-technology types, but it is conventionally fuelled low-emission cars that are proliferating at present. This was evident at the recent Sexy Green Car Show at the Eden Project in Cornwall. The show website tells us that in general, the lighter the car, the less CO2 it produces. A striking example is Axon’s new hatchback, launched at the show. It from runs a small petrol engine but what sets it apart is its ultra-lightweight aerodynamic carbon-fibre body, returning outstanding eco-stats: average CO2 emissions of sub-80g/km, and average fuel consumption of 100 miles per gallon.

Most vehicles exhibited were light, small-engine, conventional models:

  • From Peugeot – the 107 (109g/km, 61.3mpg), 207 (117 g/km, 64.1mpg) and 308 (120g/km, 62.7mpg);
  • From Citroën – the C1 (109 g/km, 68.9mpg diesel, 61.4mpg petrol), C2 (119g/km, 64mpg), and Grand C4 Picasso MPV (150g/km, 49.6mpg);
  • The Euro 5-compliant Fiat 500 range;
  • Seat’s Ibiza Ecomotive Supermini (99g/km, 88.3mpg);
  • Ford’s Focus ECOnetic (115g/km, 65.6mpg);
  • Volkswagen’s Polo BlueMotion (99g/km, 70mpg)

Volkswagen product affairs manager Angus Fitton told SB: “The BlueMotion vehicles have enjoyed significant demand in the UK and across Europe.” Fitton added: “We’re working to be able to offer a total of nine BlueMotion variants before the end of the year – the Polo, Golf, Golf Plus, Golf Estate, Jetta, Touran, Passat, Passat Estate and Sharan.”

Ford’s diesel-driven Focus ECOnetic, Which Green Car?’s Car of the Year, will also soon have a stable mate, the Fiesta ECOnetic. “It is smaller, sub 100g CO2,” says spokeswoman Fiona Pargeter. “We’re planning to unveil the car at the London Motorshow.” Ford also produces flexifuel cars, which run on either E85 bioethanol (an 85% biofuel) or unleaded petrol, or any mix of the two. Their absence at the Sexy Green show prompts SB to ask if controversy over biofuel production methods might have something to do with it.

Ford spokesman Oliver Rowe responds: “Our rationale behind ECOnetic v flexifuel is simple – go where the sales are. We were the first with flexifuels in Britain in 2005 and had high hopes for this new market. As flexifuels motoring took off in Scandinavia, Germany, France, Spain and Italy, we added the technology to C-MAX, Mondeo, S-MAX and Galaxy across Europe. In Britain, insufficient government backing and incentives held the market back and we only do around 150 cars a year.

“The food versus fuel debate has not been fairly reported. And the biofuel industry is moving towards using ingredients which aren’t human foodstuffs anyway – second-generation biofuels. In Britain, we backed biofuel projects in Somerset and East Anglia, using surplus wheat and beet respectively for locally grown crops to power locally driven cars.

“These schemes were also hampered by lack of the kind of incentive which catches public interest.”

Nevertheless, Saab chose the Sexy Green event for the first UK showing of its next generation bioethanol car, the 9-X Bio Hybrid Concept. This follows Saab’s first-generation 9.5 BioPower. When running on E85, the 9-X has projected CO2 emissions to be 105g/km, and fuel consumption 44.1mpg. The 9-X also harnesses sun power via a roof solar panel to give the car a free power boost.

Volvo is another heavily backing bioethanol, at the end of this year adding the C30 Efficiency model to its FlexiFuel range. Advance publicity promises average fuel consumption of 62.8mpg and CO2 emissions below 120g/km. And Volvo claims that, because the crop from which bioethanol is sourced absorbs CO2, the net contribution of fossil CO2 is about 80% lower than for petrol.

Volvo is experimenting with plug-in hybrid technology, as is GM. The Volvo ReCharge Concept, unveiled at the Frankfurt Motor Show, delivers a 60-mile range from its battery before the car’s flexifuel engine takes over. CO2 emissions promise to be half that of the greenest diesel.

Current hybrids are of the petrol-electric type – the Toyota Prius, the Honda Civic Hybrid and three Lexuses. The Civic Hybid, with its small 1.3-litre petrol engine assisted by an electric battery, yields 720 miles from a single tank, and emissions are 109g/km. John Kingston, environment manager, says: “In Spring 2009, Honda will be launching our next Hybrid model. The key advancement for this product is that it will be priced at a level that is significantly cheaper than hybrid models currently on the market.” He adds: “While the Civic Hybrid is the cleanest vehicle that we produce, there are a number of green clean vehicles in the Honda range”. He names the CR-V 2.2 Diesel 4×4 (173g/km) and the Accord 2.2 Diesel (155g/km).

Honda is moreover poised to become the world’s first manufacturer to offer a production hydrogen fuel cell car. Lease sales begin in the US this summer and Japan in the autumn. The exhaust pipe expels only steam. But, as for any other fuel, total emissions impact cannot be gauged until you factor in how the fuel is produced and distributed.

Toyota’s Prius was in 1997 the world’s first production hybrid car, and the Mark 2 model returns 65.6mpg and 104g/km emissions performance. Why, we ask spokesman David Crouch, have other manufacturers been slow to adopt hybrid technology?

“The Mark 1 perhaps when it was introduced was seen as a little bit quirky, and you’ve got the nervousness that some consumers have with new technology. What happened with Prius was that the second-generation model was a five-door hatchback, which historically sell better in our market. And then the technology has become much more widely acceptable.” The Prius is selling well and sales are increasing year on year, he says. “We see hybrid at the moment as the next best step to the ultimate eco-car which has no emissions and takes nothing away from the environment in the manufacturing process.”

To that end, Toyota is developing a fuel cell hybrid. The company is poised to launch a new conventional eco-product, Crouch reveals: “The iQ, a very small car, will seat four people. It’s quite a revolutionary car, a lot of new technology going into it.” The CO2 figure is yet to be announced but Crouch thinks it will be “very low, lower than Prius”.

He adds: “iQ won’t go on sale till early next year. Urban Cruiser is a little further

away, probably mid-next year. But we’re looking at a smallish 4×4, maybe Yaris-sized, sub 140g/km.”

The Toyota Yaris, with eco-stats of 119g/km and 62.8mpg, is the Environmental Transport Association’s (ETA) Green Car of the Year. The ETA, which has compiled top 10 greenest cars lists since 1992, was founded as a non-profit car breakdown service that is not part of the road lobby. The other vehicles in ETA’s 2008 top ten are: the Honda Civic Hybrid, Toyota Prius, Renault Modus, Citröen C1, Toyota Aygo, Peugeot 107, Renault Clio, and the Suzuki Swift. Other than the Prius and Civic hybrids, the entire top ten comprises conventional very light small-engine cars.

Very much in that mode is the diminutive Smart Car two-seater, which at 112g/km made it onto a separate ETA top ten for the lowest CO2 emitters. The Smart will be available in an all-electric version within the next couple of years, as will a similar car from parent company Mercedes Benz.

But electric cars – the Nice, G-Wiz and Piaggio Porter MPV now on the market – are excluded from consideration for ETA’s top lists despite zero on-road emissions. Andrew Davis, ETA director, explains: “We don’t include cars that can’t go to Birmingham from London – about 100 miles – without refuelling. But one day, electric cars will be able to do that and we’ll include them.”

Davis says: “If you think about it, I’m looking at cars now of 111g/km and 119g/km.

The way you drive and the journeys you make so outweigh the difference between a frugal car that, personally, I don’t buy the cars at the top of the guides that I produce because I drive very rarely so I can push the envelope out a bit.”

With average new car CO2 emissions, having fallen by 13% since 1997, The Society of Motor Manufacturers reports a bustling market, with a stronger focus on super-efficient small cars, and the market for alternative-fuelled vehicles experiencing a 76% growth from 2006 to 2007 with hybrids dominating.

John Procter, SMMT spokesman, says: “We can say that at £20B, the automotive sector is Europe’s largest investor in R&D, driving industry forward and helping to deliver more sustainable motoring for the 21st century.

“Much of that is being spent on a number of different technical solutions to cut new-car CO2 emissions, as there appears to be no one single technology emerging above the others. Bio fuels, synthetic fuels, electricity and hydrogen all offer the potential to reduce reliance on carbon-based fuel, but delivering sustainable low-carbon products at an economically affordable price is key to success.”

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