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10 strange alternatives to petrol
You do not have to be that old to remember when motorists used to speak of rumours that petrol prices would one day hit £1 a gallon, or when it was possible to stick in a fiver and see the fuel gauge actually move.
Today paying a fortune for petrol is something we take for granted and it is hard even to conceive of a time when no one really knew what to do with the stuff because the alternatives seemed so much better.
The first man ever to sink a productive oil well, for example, 'Colonel' Edwin L Drake, nevertheless died penniless. Similarly, until the early 1900s, the Land Speed Record was routinely broken by battery- and steam-powered machines rather than any of these new-fangled internal-combustion-engined thingies.
But slowly but surely petrol became the default choice, although we now realise that its reign will be relatively shortlived. A century ago it was just one choice among many and, with talk of climate change and fossil fuel depletion meaning tens of millions of pounds are being spent seeking out new alternatives, it is beginning to look as if the same will soon be true again.
Apparently the Swedish authorities nab some 200,000 gallons of alcohol being smuggled into the country each year. Instead of simply pouring it down the drain, or sneakily selling it on, the powers-that-be have come up with a novel solution for dealing with the confiscated stash.
Blended into a doubtless unpalatable cocktail, the booze is used to produce a form of biogas which is suitable for powering a variety of vehicles. So far these include public service buses and at least one train, although it has yet to be offered to the public to buy.
A smelly but a practical alternative to diesel, used chip fat - actually vegetable oil - is no longer free. Pub and takeaway owners (and the tax man) have all cottoned on to a useful source of extra income, although it still works out at something under half the price of conventional DERV.
If it is for your own use only you can legally avoid paying the tax. Also most cars and vans need little in the way of modification once the oil has been filtered, although some users prefer to mix it with normal fuel rather than using it neat.
Rudolf Diesel was already interested in using vegetable oil more than a century ago, and also experimented with coal dust as a possible fuel for his patented compression-ignition engine. His backers were particularly keen to find a use for the mountains of dust found in Germany's industrial Ruhr Valley.
Getting the mix right proved problematic, and after some unplanned explosions Diesel settled on peanut oil rather than the mineral oil to which his named has since been applied. Interest in coal dust has never entirely disappeared, however, and having been used in power stations it could yet make a return.
Necessity being the mother of invention, acute fuel shortages in the second world war encouraged all sorts of experimentation. In London, Edinburgh and other British cities a number of private cars and cabs (and particularly buses) were converted to run on toxic town or coal gas.
In terms of efficiency it was no match for petrol, although a tonne of coal is said to yield an impressive 3,000 cubic feet of gas and a further 1,500 lbs of smokeless semi-coke. Unfortunately, huge quantities had to be carried, using trailers towed behind buses or vast balloon bags on top of cars.
Doubtless caught up in the race to devise a perpetual motion machine, in 1911 Isaac Smyth somehow managed to successfully patent the design for a car powered by gravity. Sadly there is no convincing evidence that he ever managed to sell one.
A series of weights were hand-winched up to roof level and on being released converted their gravitational potential into forward motion via a series of pulleys and cables. Unfortunately the driven wheels had to be jacked up in order to raise the weights, and the real source of power was the driver's own muscles.
Toyota's fabulous 'Idea Olympics' is an annual event enabling factory staff to let rip with their most outrageous designs in the certain knowledge that none will ever make it into production. Previous efforts have included a pedal-powered, 22-legged centipede and a giant motorised hand which moves along by bending its fingers.
Another was the Hamster Car, which, as the name suggests, was propelled by amplifying the electric power generated by several on-board rodents running round in their traditional wheels. For short bursts of acceleration the driver merely needs to shout, "look out! Freddie Starr is behind you."
First raced in 1919, the Miller 'TNT Special' is a famous American racer, and not to be confused with an extraordinary 1931 attempt on the Land Speed Record. The Miller design used an explosive cocktail which included TNT, dynamite, nitroglycerin and petrol. Unfortunately the precise details are not known as the car itself is not thought to have survived.
In 2005 a report in National Geographic confirmed that scientists had made a significant breakthrough in their work with spray-on solar cells. Like paint, the composite can be sprayed onto other materials - even clothes, it was suggested - thereby providing a portable source of effectively free electricity.
A year later staff at the Materials Research Center at Swansea University confirmed that they too could collect the sun's rays using another paint-like material. This could one day be sprayed onto buildings or of course car bodies, turning a vehicle into one vast self-propelled solar cell.
Apparently it is perfectly possible to turn dirty nappies into fuel, a disgusting-sounding process which can usefully be disguised using the technical term pyrolysis. This involves breaking down the waste products into gas and fuel oil, the transformation thankfully taking place in a sealed container in an oxygen-free environment.
As long ago as 2007 a power company in Quebec started exploring the possibilities of this technology, spurred on by a seemingly endless supply of disposable nappies pouring into local landfill sites at a rate of 600 million a year. The end result is similar to diesel, and apparently no worse smelling.
With waste wood being generated at a phenomenal rate - a typical US sawmill processes nearly 1,400 miles of planks a year - efforts continue to produce a road vehicle powered by the stuff. The most popular route is by gasification, drawing off the vapours produced when the wood is burned under controlled conditions.
The end product, called 'producer gas', is less efficient than petroleum, by anything from 30-50%. But it is also dramatically cheaper - about 4p a gallon - even once the cost of the generating equipment is taken into account and assuming you do not have a local sawmill from which to scavenge the waste.
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