Letter from Europe: Austria's farmers welcome biogas with open arms

Thursday, June 4, 2009

Some 335 of them contribute biogas to the national grid. Now a plan is afoot to develop a tractor in part fuelled by gas produced on the farm itself

by NORMAN DUNN

There can't be many countries in the world with a government so dedicated to its farmers' well-being and business success as Austria.

Here's a relatively small Alpine republic that encourages organic management because its farms are small (average 45 acres) and because organic foods offer a much better income compared with conventional output. Generous production aid and an annual advisory budget of C$13 million dedicated to organic output mean that 16 per cent of the nation's 190,000 farms have now gone organic.

Austria's government in Vienna also does its best to cut farming costs. The country is already one of Europe's biggest users of natural gas per head with 5,000 kilometres of underground pipelines networking supplies to towns, villages and farms. And this is not only for heating. Pricing policy means that compressed natural gas (CNG) as automotive fuel has become a hit with motorists converting their autos, for this relatively new fuel is 50 per cent cheaper than regular gasoline and 25 per cent cheaper than diesel.

Typical of Austria's agricultural slant was a move by the government environmental agency to involve engineers in developing a CNG-fuelled tractor.

Steyr, a member of the Fiat/Case IH group, was among the first tractor manufacturers in Europe to produce the goods – a 200-h.p. tractor with 400 litres of CNG stored on the cab roof and running 50:50 on a diesel-CNG mix with completely unaltered engine.

So far, the CNG is metered into the air intake just before the turbo-fan for maximum mixing effect and a specially developed electronic regulator with sensors adjusts CNG supply to power demand. Now the conversion is certainly not cheap at around C$38,000 a tractor. But once again Vienna reveals its big farming heart with a farmer grant of 30 per cent for this operation.

Steyr engineers say that the remaining investment is paid back on saved fuel bills on any normal cropping unit within four to five years.

Vienna had already seen its natural gas supply network as yet another way of helping farmers. Biogas was welcomed with open arms on Austrian farms (335 at the last count). Most gas produced from fermented manure and green crops fuels engines that in turn power generators and earn the equivalent of C$0.27 per kilowatt hour fed into the national grid.

Even more efficient and just as lucrative was the next plan – to process biogas on the farm to meet the natural gas standard (minimum 97 per cent methane) and feed it straight into the national natural gas pipeline network.

The ploy has been so successful that this spring eight per cent of gas supplied through this network is actually biogas from farms.

The next step was obvious for anyone who'd watched the developments in Austria. The engineers who developed the CNG tractor – and since then a fleet of ski-hill graders, trucks, SUVs and even a natural gas Harley-Davidson motorbike – were asked to see if the same machines could run successfully on farm-produced biogas.

No sooner was the idea mooted than Steyr was out in the fields testing its CNG tractor prototype with this natural fuel.

And one of the first discoveries made was that biogas fuel is exceptionally good for the environment, as well as farmers' pocketbooks. With its 6.6-litre, V-6 turbo-diesel fed on a 50:50 mixture of biogas and diesel, the Steyr tractor cuts hydrocarbon and carbon monoxide in exhaust emissions by 87 and 97 per cent compared with pure diesel.

Carbon dioxide emissions are down by 20 per cent and nitrous oxide output by 17 per cent. Running costs reduction? About 40 per cent, according to Steyr.

Only one big problem remains. Biogas, like CNG, is compressed to over 200 bar and therefore the storage tanks on the tractor cab roof have to be made of steel with storage capacity just enough for a good day's work out in the fields.

"We are now working on new composite tanks that will be lighter and hold more gas, and we're also testing sequential injection of gas into the engine instead of just metering it into the air intake," explains Rudi Hinterberger from Steyr. "This should cut fuel consumption and also help a tank of biogas last longer."   

This newest natural fuel has to be processed first with, I understand, moisture content closely controlled and all sulphur extracted. But a number of on-farm biogas plants have already been kitted out with the required processing equipment in readiness for the time, no doubt very soon, when there'll be plenty of tractors in Austria running on home-produced gas! BF

Norman Dunn writes about European agriculture from Germany.