26 SEPTEMBER 1998, Page 60


Make your own . . .

Alan Judd

Should we emulate the Queen and the deputy prime minister — if that is still cor- rect precedence — and go for gas? Liquid petroleum gas — LPG — is allegedly an answer to the motoring component of glob- al warming (itself, of course, a matter of guesswork). More importantly, from the point of view of any one individual, it is very much cheaper than petrol or diesel.

Volvo's S70 and V70 are designed to run on both LPG and petrol, while in Holland they've been using it for 40 years, powering everything from light cars to heavy diesel trucks. They have something over 2,400 petrol stations that sell it, whereas we, with one of the highest vehicle concentrations in the world, have something less than a cou- ple of hundred. But with the government pledged to peg tax on LPG at current levels (presumably until it becomes seriously pop- ular), it could still be a worthwhile option, the more so if it qualifies for the proposed £50 road fund discount for 'clean' vehicles.

LPG is a by-product of natural gas pro- duction and oil refining. It enters your car in liquid form, just like petrol, where it is stored at about 90 psi in a tank that will withstand at least 470 psi. It is then drawn off and turned into gas by a vaporiser before entering the engine. As for safety, the range of concentration required for LPG ignition in air is actually narrower than that of petrol.

All gaseous emissions are very signifi- cantly lower than with petrol and there are virtually no diesel-type particulates. It is also claimed to yield lower maintenance costs due to smoother, cleaner running fewer carbon deposits, less wear on plugs, no oil dilution — and engines should last longer.

However, the advantage that matters for most motorists is cost: at around 39 pence per litre LPG is about 43 per cent cheaper than unleaded petrol. For meanies like me, that makes it possible to dream again of another old Range Rover, only this time I wouldn't have to drive around cursing it for its 13 mpg.

It's not all good news, though. The LPG tank supplements rather than replaces your petrol tank (you can switch from one to the other instantly), so space has to be found for it. Not a serious problem in the back of a Range Rover, in which you can also fit smaller tanks beneath the sills, but not so good in your Mini. Medium-sized saloons will take a large enough tank in the boot, but not with golf clubs or serious shopping. You also lose power, variously estimated at 3-10 per cent, while mpg suffers by 5-12 per cent, although the bigger your engine, the less you'll notice. Fitting costs vary from £500-£800 plus VAT for carburettor engines to about £1,300 for fuel injection systems. If, therefore, you do 10,000 miles per year at 20 mpg and assume an average petrol cost of about 68 pence per litre, you spend £1,543 a year on fuel; using LPG at 39 pence per litre would save you £658 a year, thus taking between one and two and a bit years to recover the cost of conver- sion. If you travel very much on the Conti- nent, savings could be greater because the cost of LPG is generally lower (in Holland it is about 20 pence per litre).

Although LPG doesn't do away with the valve seat recession problem of older vehi- cles using leaded petrol, it might make them easier to run after the proposed removal of that fuel in two years' time. Most cars can be converted to unleaded, but for those that aren't there will be upper cylinder additives to put into the petrol tank so that the car can be switched to that for a few miles before reverting to the more economical gas.

Among specialists whom I've seen rec- ommended for conversion work are Cen- tral 4X4 of Birmingham (0121 3276004), specialising in Range Rovers), Marine Eco Power of Hampshire (01590 688644) and Autogas 2000 of North Yorkshire (01845 523213). Autogas, who have 30 years expe- He or she was never mentioned in the tabloids.' rience in the business and whose prices range from £700-£1,200, also publish details of the procedure and a list of LPG suppliers on their Internet web site, HTTP://www.autogas.co.uk. Main suppli- ers such as Calor (0800 992200) and Flo- gas (01530 230352) may provide further information.

The economics of conversion you can work out for yourself — the bigger your vehicle, the higher your mileage and the longer you keep it the more it pays (of course, you could buy a Volvo to start with) — but the availability of LPG is the problem for most people. It will doubtless improve rapidly but it will still take time before there is reasonable coverage. High mileagers with 10ft of clear space and another ten for the vehicle might consider having their own tanks installed. Both Flogas and Calor will do this for you and charge you rent from about £50 a quarter, with LPG prices from about 17 pence a litre plus duty and VAT, which works out a few pence less than the forecourt prices.

Alternatively, rural leaders could run their cars for almost nothing if they're prepared, like one farmer I read of, to derive their gas from chicken manure. Or just think of the gas potential of the sew- erage of London, freely donated by mil- lions of your friendly-fellow citizens. Technically possible, perhaps, but could this government resist taxing it at source?