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Will We Ever?

Will we ever… stop driving petrol-powered cars?

About the author

Steven Ashley is a freelance science/technology writer and editor. Currently a contributing editor at both Scientific American and SAE Automotive Engineering International magazines, he also contributes frequently to The New York Times, txchnologist.com and ecoimagination.com. Ashley has edited and/or published in periodicals including Popular Science, MIT's Technology Review, Physics Today, Aerospace Engineering and Manufacturing and Mechanical Engineering. Ashley also edited much of the James Beard Award-winning cookbook, Modernist Cuisine: The Art and Science of Cooking.

Will we ever stop driving petrol-powered cars?

(Copyright: Thinkstock)

Despite a growing number of greener alternatives, Steven Ashley explains why the gas-guzzling internal combustion engine will still be on the roads for the foreseeable future.

I get asked this question a lot, often on long airline flights where you can easily alienate a seat companion with an answer that he or she does not wish to hear. Given that passions often run high among both lovers and haters of gas-guzzling cars, it’s a hard question to answer (safely). And the truth of the matter is, I don’t really know.

But over the course of decades, I’ve had the chance to put this question to all manner of experts in the field – the world’s best automotive engineers and business executives, technology specialists and experts, top scientists, researchers, lab managers, technical authorities, designers and economic pundits, green activists, military and political leaders. Now admittedly, some of these individuals can be classified as biased or interested parties (after all, there’s a whole industry out there with armies of employees dedicated to the promotion and welfare of the car engine), but my ‘expert panel’ represents a reasonably fair and measured sampling of the proverbial best minds on the topic. All speaking freely, usually off the record, so take this as you may.

And the overwhelming result of my private, unscientific, ongoing ‘poll’ is clear: despite significant advances in green or electric vehicle technology, the internal combustion engine is here to stay for the foreseeable future, at least to the end of this century.

So why’s that?

Lingering suspicion

Several things influence this consensus of opinion. One is that green technology –pretty much all of it of any significance – has been mandated by governments. If the green movement and subsequent green legislation hadn’t driven the global car industry to cut exhaust emissions and go electric, we’d all still be cruising the boulevard with big-block V-8s up front. But could governments go the extra mile and truly convert the car business to an environmentally sustainable operating basis in the long term? The expert panel remains pessimistic.

Another factor seems to be the lingering suspicion, if not conviction, that the process of transforming basic technologies among large populations is more often than not a very slow process, one that requires considerable innovation and capital investment, two resources that always seem in short supply. Germany and Japan, for example, are now finding out how difficult (and dirty) it is to pull nuclear power off the grid.

A third, more technical, point is that oil and its derivative fuels still hold huge advantages over all of the alternatives for transport use (especially if you don’t mind dumping the combustion trash into the atmosphere).

So backed by more than a century of steady and even intensive research, development and engineering efforts, the internal combustion engine today sets a high performance standard for low-cost, effective vehicle propulsion, one that has even partially cleaned up its act in recent years. Conversely, the growing use of fossil fuel-based electricity generation – China, for instance, the world’s biggest car market, builds a new coal-fired power plant each week – tends to undercut the argument for more electric vehicles in terms of the technology’s total environmental footprint.

Finally, although the ‘experts’ readily acknowledge and applaud the remarkably effective progress that green and electric vehicles have made in recent years, they tend to believe that electric propulsion is really not there yet as a substitute technology, and probably won’t reach the market in a fully capable form that can go for 300 miles or more on single charge at an affordable price for some time to come.

How long that takes is anybody’s guess. It depends to a great extent on your crystal-ball view of the global economic future. Probably decades, even without a Eurozone crisis or oil shortages. Note that the latter issue may or may not prove fatal to the petrol-driven car – thus potentially answering the question for good. And even when high-performance, affordable electric cars start hitting the roads, you’d have to wait for who knows how long until the entire auto fleet could be converted – until that day when the last exhaust-spouting car engine dies out...

Range anxiety

There are also a couple of related realities that people typically don’t always think about, but that are worth mentioning.

Firstly, the most popular of the green/electric vehicles, gas-electric hybrids, burn fossil fuels in engines. And hybrids are regularly touted as the transition technology to the electric car. It is perhaps ironic that of all the alternative propulsion technologies on the market it is hybrid technology that has probably saved more transportation fuel than anything else tried so far. You’d expect such an efficient transportation technology to have a relatively long operational lifetime.

Second, no matter how electrified passenger cars get, trucks, their omnipresent counterparts on roads and highways are not going electric any time soon, that is, barring the emergence of some unforeseen, revolutionary high-capacity battery or other advance. Nobody knows, for example, how to efficiently propel heavy tractor-trailers, long-haulers and larger transports without burning fuels in big internal combustion engines, hybrid power plants notwithstanding. And medium-size trucks probably need engines as well. So the fuel station is probably a keeper.

For smaller trucks like pick-ups and SUVs, the issue is a bit cloudier. Most ‘experts’ don’t think that electric batteries, even improved ones, will be able to drive small trucks in the short- or mid-term, so that’s why the car companies and governments are still sticking with the poor cousin of electric propulsion family, the hydrogen fuel cell. Though long ignored by most, fuel-cell vehicles have shown that they can haul larger loads. But like electric vehicles and the public/private recharging infrastructure that makes it all run, fuel cell-powered vehicles and its hydrogen infrastructure would be costly to build, and have yet to materialise.

Still, I always try to be optimistic about the world’s survival prospects and try to keep an eye out for potential breakthroughs. Thankfully one arrived in this week’s Science magazine.

Researchers at the University of St. Andrews in Fife, UK have demonstrated an early form of an improved, high-power electrochemical cell – the lithium-air battery. Such a device could theoretically provide some four to ten times the energy density per weight that conventional lithium-ion batteries do, which would banish EV ‘range anxiety’ and make electric vehicles fully practical. Today’s lithium-ion batteries can provide power for about 100 miles before needing to be recharged and nobody wants to be stranded with a dead battery.

“We need to go beyond the 300-mile driving range for EVs, so we need a transformational shift. Lithium-air batteries have the potential to provide it,” says Peter Bruce, lead researcher of the study, who describes himself as a battery specialist “for longer than I care to think of”.

Note the word “potential”. Their findings are essentially a proof of concept. That said, it is this type of breakthrough that could prove to be a stepping stone toward a golden and perhaps achievable, goal.

And that gives me hope.

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