By Jorn Madslien
Business reporter, BBC News
Market forces have sparked an obesity epidemic in the car industry, according to automotive industry expert Professor Garel Rhys of Cardiff Business School.
Car makers insist they are working hard to cut emissions
"We looked into it and to our amazement, we found that cars are getting heavier," says Professor Rhys, speaking as the car industry body SMMT released its latest report on the emission of carbon dioxide, which contributes to global warming.
"The weight element has gone straight out of the window."
"Weight has been increasing by about 1.5% per year over the last 10 years," confirms Greg Archer, director of the Low Carbon Vehicle Partnership.
The automotive weight-gain is counter-intuitive, given that cars these days are built using lighter and more rigid steel than in the past.
"Steel isn't steel isn't steel," explains Professor Rhys. "We now have very clever steel."
The industry tends to blame the additional weight on regulation that requires them to load cars with heavy safety equipment.
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Professor Rhys sees a couple of additional reasons. As vehicle weight came down, their designers saw it as "a chance to load up with seven speakers", Professor Rhys adds.
Manufacturers have been adding a slew of electronic wizardry to their cars - ranging from satellite navigation systems and climate control units, to electric sunroofs and doors that close at the touch of a button - all to boost sales and profits.
Indeed, as electronics prices have come down, such added extras have in effect bolstered the carmakers' hard-pressed margins.
Moreover, as is often the case in humans, the automotive weight gain has been coupled with bulkier shapes.
Increasingly, observes Professor Rhys, car makers steer away from the aerodynamic "egg-shape" as they struggle to make their cars appear different from those made by rivals.
"The market has become so competitive," observes Professor Rhys, "it's desperation to get your share of the market."
No miracle cure
The result of all this added weight being piled into cars - which have been designed more for visual impact than for efficient streamlining - is increased fuel consumption and, thus, a rise in emissions of carbon dioxide.
"Advances in engineering have been cancelled out by more equipment," says Mr Smith.
And there have been many such advances, Mr Smith insists.
In just four years, the energy used in the manufacturing of cars has halved, he points out.
That is significant, given that 10% of the energy consumed during a car's life goes into its production, with a further 5% consumed during its dismantling and recycling.
In addition, petrol and diesel engines have become ever more efficient. So although the number of cars on the roads in Britain rose 16% from 1997 to 2005, the overall CO2 emission from cars has come down slightly.
Besides, pretty much all car companies are searching for alternative power sources.
These include hydrogen, which Professor Rhys points out is "energy-intensive and filthy" to produce; petrol-electric hybrid cars, which "are very heavy, by definitions, since they have two powertrains"; and biofuels: "you get rid of CO2, but you starve in the interim."
Professor Rhys sums up: "The technologies and solutions that are being put forward at the moment; there's nothing that stands out head and shoulders ahead of anything else."
"The only thing in the last 100 years that has challenged petrol is diesel," says Professor Rhys. And that, he points out is nothing but another diversion, since it too emits CO2.
The car industry says consumers have a role to play
"There's a difference between an engineering - and thus an environmental - optimum and a commercial one," says Professor Rhys.
"Concorde was a wonderful engineering solution. Commercially, it was a nonsense."
In other words, new technology can only help cut emissions if the people who buy cars accept it.
The industry wants the government to step in, to offer incentives to consumers prepared to shy away from the cars they like and, instead, buy the cars they ought to like.
As it happens, consumers are gradually turning towards green cars, and the industry is already making the most of any green credentials they identify.
This, however, has led to accusations of "green-washing", where some automotive firms make out that their solutions are better than they actually are.
"We need rules to address green claims made in advertisments," says Mr Archer.
"You don't need to focus to the extent we currently see on power or performance. There are better ways to advertise."