ENVIRONMENTAL CARS OF THE FUTURE
THE world is running low on oil, many people are concerned about vehicle emissions – though livestock, factories and power generators are big culprits – and there’s an undoubted momentum for high-tech cars that are more friendly to the environment.
Cars are now more fuel-efficient when using petrol and diesel, but those fuels are not going to be available at a reasonable price for long.
LPG has become cleaner but it, too, is non-renewable energy and interest has waned since the wind-back of subsidies for LPG conversions.
It leaves ‘‘flex-fuel’’ ethanol, hydrogen fuel and electric vehicles as the potential booming types.
Hybrid cars have an electric motor supplemented by a conventional internal combustion engine. So far, the Toyota Prius, Honda Civic hybrid, Lexus GS450h, LS600h and RX450h SUV, the new Porsche Cayenne hybrid SUV and the Australian-built Toyota Camry hybrid are production vehicles offered for sale in Australia and driven as normal cars.
They gather power for their batteries by harnessing energy from braking but still have limited range on electricity before the engine cuts in to help.
These hybrid models use petrol engines. But hybrid cars also can use diesel, LPG, ethanol or even natural gas engines to assist the electric motor.
‘‘Every car manufacturer has a hybrid car or will have by 2012,’’ says Motor Trade Association state executive director John Chapman.
Mr Chapman has just unveiled the MTA Prius, a hybrid Toyota with standard battery pack replaced by batteries with greater capacity. They allow the car to travel up to 40km before the petrol engine cuts in. But most importantly, the batteries can be recharged from a domestic electric wall socket.
The higher-capacity batteries, installed for $15,000, take up more space (replacing the spare wheel) and add about 110kg but performance is untroubled due to the high torque of the electric motor from rest.
Mitsubishi has the first of its cute little i-MiEV cars being evaluated in Australia. It is on sale in Japan, as is the Nissan Leaf. Both are electric-only and plug in to recharge. More such plug-in electric vehicles (EVs) are on the way from other makers.
GM is developing its Volt (we can expect a Holden Volt in a few years). It has a plug-in electric motor, and an engine that does not directly propel the car but starts up to generate electricity for the batteries – a sort of onboard power station.
Perhaps 35 years ago I drove a Flinders University electric vehicle, the little Fiat being weighed down by batteries that looked similar to normal car batteries. But now advances in lithium-ion batteries, similar to those in mobile phones, have allowed EVs to be more practical, have charge topped up and give real performance. Last year I drove the first Tesla roadster in Australia, owned by Adelaide’s Simon Hackett. It swooshed from 0 to 100km/h in a supercar-like four seconds with no more sound than an expensive vacuum cleaner. Range? Mr Hackett drove it 501km in last year’s Darwin-Adelaide Green Global Challenge on one overnight recharge.
An issue, especially for environmentalists, is how the electricity is generated in the first place. Electric cars have no CO2 emission when driving, but the electricity they use has to be generated, usually at a power station. But individuals can have solar arrays on their roof to gather electricity and feed it back into the power grid so that when they recharge their plugin EV, it is effectively at zero emission.
EVs are best used for daily, short city and suburban trips, then recharged again overnight. Some say that you’ll be able to do, for example, an Adelaide-Sydney drive by stopping at battery-change stations to robotically have your almost-spent batteries taken out and fully-charged ones put in within minutes while you have a rest stop. But will we have enough demand for such stations?
Meanwhile, hydrogen can be used in two ways. It can fuel an internal combustion engine. Or, more likely to be seen on our roads within a few years, it can feed an on-board ‘‘fuel cell’’ which creates electricity for the electric motor. Hydrogen is plentiful. But the problem is extracting it – again, we’d need a lot of solar power or wind power to do so – and there is an issue of carrying highpressure bottles in the car. Then we’d need hydrogen fuel stations at which to refill.
Ethanol fuel is used by many motorists already, at a 10 per cent blend with petrol. But cars, if tuned and built with components that cope with its properties, can run on up to 100 per cent ethanol. V8 Supercars use 85 per cent blend for their racing.
Ethanol is renewable energy: it comes from plant stock such as sugar cane. But the world needs to be careful that such crops are not grown at the expense of food – another issue the world has to face.
Either way, the motoring future is here as soon as tomorrow.