TURN BACK THE CLOCK

23 March 2001




With the government offering

substantial cash incentives,

you might consider running

petrol farm vehicles on lpg.

But you have to speculate

to accumulate, as

Andrew Pearce discovers

TURN BACK THE CLOCK

ON HIGH FUEL PRICES

FANCY turning back the motoring clock to 1984? Filling up with liquefied petroleum gas (lpg) at 38p/litre lets you do just that. And bought in bulk, the price drops to 29p/litre – the same as petrol two decades ago.

Either carburettor or injection petrol engines can run on lpg, alias autogas. Environmentally this is friendly stuff. When burnt properly it gives substantially lower levels of the chemicals that make you splutter, particularly compared with diesels. And the good financial news spreads to the prospect of vehicle conversion grants and lower servicing charges, the latter stemming from less contamination of engine oil and plugs.

So why arent we all gas-powered? Historically, thanks to the poor efficiency of early conversions and a dire lack of filling stations. Fill-up points are now thicker on the ground and todays conversions can be much more fuel-effective. But a vehicle still has to jump through the right hoops to land a government conversion grant. So what is the reality for farms interested in cutting operating costs?

&#42 The nuts and bolts

Dual-fuel vehicles run on either lpg or petrol at the click of a switch. There is no reason why lpg should not be the only fuel carried, but the conversion market centres around adding lpg alongside petrol.

Conversion kits come mainly from Italy and Holland. All have the same basic bits – an lpg tank; a vaporiser plus mixer or injectors to deliver gas to the engine; various solenoids to direct the flow of fuels; a coupling for tank filling and (on injection engines) an electronic module to communicate with the engines existing management system and vary gas flow. In the cabin a small dash unit switches between fuels and shows lpg tank contents. Engines start from cold on petrol, then within a minute or so switch automatically to lpg if required.

The petrol fuel system is left intact, so operating range jumps significantly. But the new lpg tank must go somewhere. The cheapest option is to put in the boot or load bay, though to preserve space one or more tanks can displace the spare wheel or fit under the vehicle.

What is the effect on fuel consumption and performance? We have some figures (see Spot the Difference box). One litre of lpg packs less energy than one of petrol, so in principle you wont go as far or as fast. Performance drop depends on the kit used, the original fuel system and the condition of the engine. At one end of the scale, factory-developed multipoint gas injection loses around 3% power and 5-15% in economy. At the other, basic single-point mixer designs reduce power by up to 10% and economy by 20%-25%, though if paired with the latest, highly-efficient petrol motors they drop economy by 30%-40%. Such engines call for special solutions (see Why Not Grants For All? box)

Vauxhall provided the test car. And right now it is the only maker to sell you a dual-fuel commercial out of the showroom, though its Astra and Combo light vans are converted on contract rather than in production. Daewoo and Nissan saloons are handled the same way. Ford and Volvo will offer models later this year. No car manufacturer yet sells a 4×4 off the shelf and Land Rover has no plans to do so. Thus agricultural parties must look to the aftermarket.

&#42 Who does the job?

A whole culture of firms offering autogas conversions has appeared.

Standards of work and kit components vary, often with a direct impact on the efficiency, driveability and possible safety of the end product. As usual, you pays your money and takes your choice, but bear the following in mind:

&#8226 Use of a registered installer is a requirement for a rebate on conversion cost. PowerShift (the governments alternative fuel agency) and the LP Gas Association both run approved installer schemes. To join, a conversion company must have its staff trained and examined and its premises and methods inspected. Only approved installers can issue a Code of Practice (COP) certificate with the finished conversion.

&#8226 Without that COP certificate some insurers will not cover the vehicle. Others will ask for an engineers report and may load the premium. Note: The NFU Mutual covers approved installer conversions happily.

&#8226 Without sight of a COP certificate, garages may refuse to service an lpg vehicle and filling stations may not allow fuelling. It is also not possible to register the change of fuel with the DVLC, which in itself can have insurance implications.

Can you do the job? Not a good idea. Setting aside the points above and ignoring the safety implications of getting something wrong, even a simple carburettor engine kit must be set up properly if it is to deliver good performance and economy, a job needing experience and a gas analyser. Tweaking fuel injection kits is more complex still, and most registered installers wont consider setting up a home-fitted kit.

&#42 What is it going to cost?

The price premium on manufacturers new cars is £1600-£2000, depending on VAT, model and maker.

In the aftermarket expect to pay £1100-£1600 for a straightforward conversion to a van, pickup or 4×4, with cost rising where bodywork needs to be modified or cradles added to accommodate underfloor tanks. Dual-fuel versions from a makers showroom carry the normal models warranty. Aftermarket conversions usually invalidate any remaining makers cover, so supplement warranty on the kit itself with protection for the rest of the vehicle. Registered converters generally offer insurance-based schemes designed specifically for the job.

Autogas is 50% cheaper than unleaded. The government has pledged to maintain this gap until 2004, but as lpg use grows it remains to be seen how long it lasts.

&#42 Can I get a rebate?

Only if your vehicle is under one year old, has covered less than 25,000 miles and is on the PowerShift register (www.est-powershift.org.uk). Here, vehicles are grouped in bands according to the reduction in emissions after conversion, with the biggest cashback going to those benefiting most. Four bands are laid out:

&#8226 Band 1: Vehicles not meeting minimum standard or with emissions not yet proven.

&#8226 Band 2: 0-49% emission reduction.

&#8226 Band 3: 50-64.5% emission reduction.

&#8226 Band 4: Over 65% emission reduction.

The following grants then apply, albeit only to the extra cost of buying a new vehicle or the cost of converting an existing one.

&#8226 Band 2: 40% of extra cost.

&#8226 Band 3: 60% of extra cost.

&#8226 Band 4: 75% of extra cost.

Grants are not retrospective so you cant convert and then ask for cash back; everything must be agreed in advance. Application forms come from the PowerShift web-site or hotline (0845-602 1425). Registered installers will check applicability to your vehicle, and some will find a suitable motor for you. Refunds arrive several weeks after conversion.

&#42 Achieving a bulk supply

Across the UK some 660 service stations now have lpg pumps. But for farms, an lpg tank in the yard is the way to go. While it is possible to buy a pre-fabricated installation for £4000-£5000, rental is the most common option.

Gas suppliers rent bulk set-ups subject to a minimum annual lpg throughput. Calors 10,000 litres/year requirement suits smaller businesses, equating to one vehicle averaging 25mpg over 55,000 miles, so farms would probably need to run more than one lpg vehicle or share a tank. After a site survey (£300-£400) and once a concrete plinth and 240V power supply are provided to specification, a lorry delivers a pre-built skid unit complete with protective barriers, ready to plug in and go. Rental is £68 a quarter.

Do not forget the planning angle. If this is not covered in the initial survey, applying for an Agricultural Determination (about £35) will prompt your local office to check whether permission is required. This depends (among other things) on the installations size and its position relative to a road or listed building.

A bulk lpg tank can be filled with vehicle fuel for 29p/litre, inclusive of duty and VAT.

Below: Vectras switch selects between fuels, with engine automatically starting from cold on petrol then going over to lpg within a minute or so. Aftermarket systems have a set of LEDs built into the switch to show gas tank contents, though accuracy varies.

Once the site is prepared according to specifications and mains power supplied, a complete bulk skid unit can be bolted in place. Rental for a basic set-up includes a transfer unit but not a metering pump as here.


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