Alternative Fuels

Petrol is liquid energy. As a fuel, it’s so damn good that few people even stop to consider it. Every time you stop at a service station and buy 60 litres of the stuff (90 bucks, thanks very much), you’re taking on board an astonishing two billion Joules of energy. Let’s leave the physics lesson aside; it’s a monumental dose of energy. The whole process takes, say, three minutes. If you want to get that much energy out of a standard domestic power point, it’ll take you between nine and 10 days.

For $90 you just bought the same capacity to do hard, physical work as 400 big, strapping slaves toiling full-time for you, for a week. Just a century ago, the access to that much energy, that fast, and that cheaply, would have been unthinkable. No wonder the human race is addicted to it.

A barrel of crude oil is 159 litres (about half of it becomes petrol). You can rip that barrel out of the ground for about $1.50 in Saudi Arabia (two-thirds of the world’s known reserves of crude are in the Middle East) and sell it on the New York Mercantile Exchange for about $100 – a 7000-odd per cent markup. The human race does this about 1000 times a second, 24/7. It literally makes our world go around.

What a pity it’s running out.

We Aussies consumed about 52 billion litres of transport fuel (petrol, diesel and jet fuel) in 2010-11. If you want to put that much fuel in a box, you need a box about as big as a football field at the base, and 5.2 kilometres high. If you could find a box like that, it would dwarf every building in the world.

The consensus view of oil industry experts is that ‘peak’ oil – the time at which oil production peaks globally, and then starts diminishing – has either just happened, or will soon happen. The burgeoning economies of China and India are just coming to the ‘oil’ party, only to find the keg half empty – and each of them has the capacity, independently, to double the number the number of cars on earth by the time they enjoy the same car ownership, per capita, as us.

Car makers are working feverishly on two things: fuel efficiency (driving each litre further) and alternatives to petrol and diesel. They’re having a lot of success with the first initiative, and not enjoying so much traction with the second.

HYBRIDS

Hybrids (think: Toyota Prius) are currently the darlings of the ‘save the planet’ set. They combine a conventional petrol engine with a battery and electric motors, and they do something of a magic trick with energy management. See, every time you stop in your conventional car, the brakes turn the energy you’ve acquired from moving into heat. You lose it, and you never get it back. When you’re in a hybrid and you hit the brakes or coast downhill, the electric motors become generators. They turn some of your energy into electricity, which gets stored in the battery. When you’re stopped and the lights go green again, you can lunch off that stored energy to help get you up and running.

This so-called ‘regenerative braking’ is also used by electric vehicles to extract maximum cruising range from each charge.

Hybrids are also available with a twist: some can be plugged in overnight to a powerpoint to top off the battery. These are what’s known as plug-in hybrids.

If you’re thinking about buying a hybrid you need to bear in mind that they only perform their magic during city driving. If you do long runs on the open road, there’s not usually much braking, so the hybrid system becomes, effectively, just excess baggage. On long runs, a modern diesel engine will be the most fuel efficient choice, offering about 30 per cent better economy than petrol.

Hybrids are also still significantly more expensive than conventional cars, and they depreciate more rapidly as well. We’ve had hybrids in Australia for about 10 years now, and there are several onsale today across a range of prices. In the first six months of 2012, about a quarter of a million cars and SUVs were sold to private customers like you and me. Of those, a little more than 2000 were hybrids – less than one per cent.

ELECTRIC

Driving al electric car for the first time is a very strange experience. Because there’s no fire under the bonnet, because there’s no pistons bouncing up and down at warp speed, no valves clattering open and closed, and no hot gas hurtling through four-metre-long tubes under your feet, they are dead quiet.

This fact has prompted advocacy groups for the blind in the USA and Europe to call for legislation that mandates a minimum noise level that electric vehicles (EVs) to emit – for the safety of blind and visually impaired pedestrians.

Electric motors are very different to internal combustion engines. For starters, there’s no transmission required, and no clutch (an electric motor is quite happy to sit there, stopped, when the lights are red).

When the lights go green, electric motors are amazing. They make their maximum torque just off the mark, so your initial forward progress is very rapid indeed. And because they’re so quiet, it’s easy to look down at the speedo and find yourself speeding. This is because 60km/h is much noisier in a conventional car.

There are some real problems with EVs, however. The bottom line is that batteries – even the most advanced batteries available – can’t store anything like the same amount of energy as a 60-litre tank full of petrol. In fact, if you wanted to do that, you’d need a lithium-ion battery like the one in your smart phone, only two cubic metres in size. It would weigh three-and-a-half tonnes.

For this reason, EVs tend to be tiny, tiny cars, not much bigger than a golf cart. Even then, they tend to have a range of about 100-130km depending on how you drive them. And they’re very expensive – about $50,000.

They also take a long time to recharge. There are two reasons for that. Firstly, not very much energy comes out of a domestic power point, so you’re looking at six to eight hours to ‘re-fuel’ – even if you connect to a (literally) amped-up 15-amp outlet. Even if you have access to electricity on a truly industrial scale, you have to be very careful about tipping it into a battery too fast: they have the pesky habit of overheating, and then blowing up.

EVs are uncommon on Australian roads – the most widely publicized worldwide are the Mitsubishi i-MiEV (it’s pronounced ‘eye-meev’) and the Nissan Leaf. In the first six months of 2012, just 52 EVs were sold in Australia. The demand for EVs globally has been tremendously slow – so slow, in fact, that Mitsubishi has been forced temporarily to stop production of the Citroen C-Zero and Peugeot iOn, which are re-badged versions of the i-MiEV available overseas

Basically, $50,000 for an EV is around three times the price of the cheapest conventional small cars onsale today. These offer broadly similar performance, and don’t have to stop to recharge – twice, for six to eight hours each time – if you want to spend the weekend away in, say, Canberra, Mudgee or Forster.

EXTENDED-RANGE EV

One car that offers (almost) the best of both worlds is the Holden Volt [note: goes onsale next month, I think]. The Volt is basically a Holden Cruze with a completely different drivetrain: a battery and electric motor that allow it to operate as an EV for short trips, and a petrol-powered generator that kicks in and keeps the battery topped up on longer trips.

Holden says the $60,000 Volt will go “up to” 64 kilometres on electric power alone, but it has basically an unlimited range once the generator kicks in – provided you keep topping it up with petrol. The company also claims the Volt will consume “on average” less than half the petrol of a plug-in hybrid. Like the plug-in hybrid, the Volt can also be plugged in to recharge while the car is parked, for example, at home overnight or at the office during the day.

Holden says you’ll save about 1900 litres of petrol annually in a Volt, compared with a conventional vehicle with fuel economy of 7.8 litres per 100 kilometres – provided you drive 64 kilometres per day. (The average car in Australia drives 40 kilometres per day.)

The Volt is currently the top-selling rechargeable car in the US, ahead of Toyota’s plug-in Prius hybrid and Nissan’s Leaf EV. But in America the Volt retails for about $39,000 – before a federal government tax credit of $7500. Here in Australia the Volt’s biggest problem will be price: at $60k it’s twice as much as the Cruze, with which is shares the same bodyshell – and there’s no tax kickback on the table.

HYDROGEN POWER (IT’S A GAS)

As interesting as hybrids, EVs and even extended-range EVs are, they will never be a solution to the end of oil. Hydrogen is the answer. Cars in 30-50 years’ time will routinely use a ‘hydrogen fuel cell’ instead of an internal combustion engine.

Hydrogen fuel cells are like batteries. They combine hydrogen and oxygen to form water, a process that generates electricity. As long as you keep pumping in the hydrogen and oxygen, fuel cells keep pumping out the amps – more than enough of them to keep even large vehicles moving.

The technology has been around for 50 years. NASA used hydrogen fuel cells to generate electricity in the Apollo spacecraft. It was an explosion in one of the oxygen tanks that rocketed Apollo 13 to notoriety.

Many car makers have prototype fuel cell vehicles in operation today. I’ve driven one in South Korea, in a medium-sized SUV. It was just like driving a big EV, which is essentially what it was, albeit sucking hydrogen from a tank at 10,000psi in the boot, and oxygen from the air. The only tailpipe emission was water … which they told me was clean enough to drink. (Yeah, I did drink some.)

Where will we get the hydrogen from? Sunlight. Every day, 20,000 times more solar energy hits the earth than we burn in the form of hydrocarbons. If we can harness a fraction of that, it’s child’s play to split water into hydrogen and oxygen, and enjoy emissions-free, sunlight-powered mobility for as long as the sun lasts.

As long as we get the timing right, the end of oil doesn’t have to end in a bleak manner.

Cars powered by sunlight. No pollution. Unlimited mobility. It sounds too good to be true, doesn’t it?

Stand by. It’s coming. Some of the best minds in the business are on it.