For many people, the idea of strapping yourself in to what is essentially a coffin on wheels for up to 40 minutes at a time, would be hugely unappealing. However, that's exactly what hundreds of students from university teams all over the world did at the Shell Eco-marathon, in a bid to be crowned the world's most energy-efficient drivers.

Shell has been running the Eco-marathon in some form or another since the late 1930s, when employees made bets with one another as to who could travel the furthest on the same amount of fuel. In 1985, the competition began in its official capacity, challenging students to design, build and then race their own ultra-high-efficiency vehicles against one another. There are three different Eco-marathon events - one in the Americas, one in Asia and one in Europe.

Students choose between two categories of vehicle - the practical Urban Concept class, and the futuristic and highly aerodynamic Prototype class. We were given a chance to have a go in both ahead of the London leg of the Eco-marathon.

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Taking to the track in Shell’s Urban Concept

The first machine we got behind the wheel of was Shell's own Urban Concept vehicle (below). Built to the same specifications the students' vehicles would be, the stripped-out single-seater resembled a car that might have been taken straight from a children's book.

With only one lap of the 1,669-metre-long track to try and prove just how efficiently we could drive the Urban Concept, we set off incredibly gingerly. A quick briefing prior to starting instructed us to get the car up to speed, and then coast for as long as possible.

In theory, this sounded easy enough to do. But as soon as we got moving, the technique began to feel incredibly counter-intuitive. The urge to keep our foot constantly on the accelerator pedal was nearly overwhelming - especially when you're close to coming to a complete standstill.

Nevertheless, we persevered, only occasionally pressing the throttle to rev out the incredibly noisy petrol engine that sat right behind my head. Refinement is not something the Urban Concept was built for, it would seem.

Shell Urban Concept vehicle

After bumping and rattling round a good section of the track, we began to get into a rhythm and were becoming much more accustomed with the Urban Concept's incredibly basic steering set-up and one-wheel-drive powertrain.

Eventually, we managed to complete the lap of the track with no real clue as to how well we did. After clambering out, we was informed by some rather surprised-looking engineers that we had managed to do the most economical run of the day - not bad for a first attempt.

We prepared to strap ourselves into what was the highlight of the afternoon - the aforementioned coffin on wheels. This was the Shell Eco-marathon Prototype Vehicle, or SEM 03 for short (main picture).

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Introducing Shell’s futuristic prototype vehicle

The three-wheeler looks unlike any vehicle you might have seen before. Its long, sleek body has been designed to slice its way through the air with the greatest efficiency in order to make it as fuel efficient as possible. It's just over three metres long, and stands 700mm tall. All up, it weighs just 70kg - about the same as yours truly.

It's powered by a 163cc, single-cylinder Honda GX160 petrol engine that develops a miniscule 4.8bhp. However, this clever combination of a low-drag shape and tiny engine means the SEM 03 can achieve an economy figure of greater than 500mpg - in the right hands, that is.

While there was no chance we’d be able to get anywhere near that figure, we were still riding the wave of confidence that had swelled up off the back of our run in the Urban Concept.

That confidence was dampened somewhat after we had lowered ourselves into the SEM 03 cockpit. We very quickly become aware of just how little space there was on offer. Our feet were squashed down into the prototype's conical nose, shoulders were hard up against the sidewalls and once the roof had been fastened in place, we couldn't move our head at all.

No wonder a number of others had outright refused to take the SEM 03 for a spin.

Shell Urban Concept vehicle

Test driving the SEM-03

We’d been instructed that the driving technique for the SEM 03 was slightly different to that for the Urban Concept. Whereas the latter required lengthier periods of acceleration to get it up to speed, with the SEM 03 we were supposed to squeeze the throttle for two seconds before allowing it to coast - letting its aerodynamic body work its magic.

And work its magic it did. The difference between just how far the Urban Concept and the Prototype could travel under their own momentum was immediately noticeable. Being so low to the ground, the sense of speed you got from the SEM 03 was also much greater - and far more exciting.

The lap in the SEM 03 took much less time than in the Urban Concept, and when we eventually crossed the line we were confident we’d done a pretty economical run. However, our aspirations were soon dashed.

The engineers explained that while a slow and cautious approach worked in the Urban Concept, a much more aggressive driving style was required to get the most out of the Prototype. We immediately wanted to have another go - but unfortunately the 'one lap only' rule stood strong.

Having gone in thinking there wasn't much fun to be had from a competition that emphasises driving as economically as possible, were pleasantly surprised to find that the reality was the complete opposite.

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