Calls for urgency on biomass schemes

Press, 27 February 1981, Page 9

Calls for urgency on biomass schemes

PA Blenheim Urgency in moving to- ■ wards replacements for Maui gas — now, not - when it runs out — was the theme of two papers presented at a gas-in-dustry conference in Blenheim. Dr D. Stewart, of the Invermay Research Centre, told the conference that efforts to provide . continuing gas supplies should not be left until existing stocks ran out. Unless new alternatives ' were developed, he said, the entire industry was likely to follow the path " of the South Island — ‘‘ending up selling electric ranges on the gas-show-•r room floor. “If the lobby of the oil •• companies to keep their pumps supplied with ‘ liquid fuels is heard louder than the claims of the " gas industry that the pipelines be filled with gas, r the end of Maui will be the end of the gas in- . dustry in New Zealand.”

By the year 2000 there would be an extensive gas-distribution network, with factories, homes, offices, and vehicles depending on gas. Plants would be making methanol and synthetic petrol from gas 'fTHfe two most likely future gas sources were coal and‘ Biomass, • Dr- Stewart said. (Biomass is the collective name for all biological mass on earth and includes animal, trees, and their wastes, such as garbage and manure). Dr Stewart said biomass was not a new source of gas: the Maui gas field was the result of bacterial action on biomass from times when dinosaurs roamed the earth. Coal and oil were also fuels produced from biomass. Today the biomass production rate could provide more than 10 times the world’s energy requirements. Dr Stewart said there were reported to be seven

million biogas plants — ranging from small home plants to district power stations — in China today, A recent estimate suggested that the toal output was equivalent to three million barrels of oil a day — almost exactly equal to the Maui field’s total ehergy content If. gas produced from crops was to replace that obtained from Maui in the year 2000, about 80,000 ha of farmland would have to be planted. That was 3.4 per cent of New Zealand’s total land area, and a similar amount of land to that now planted in exotic forest. Dr Stewart told the conference that coal was probably the most obvious source of gas because it had been the basis of the manufactured gas industry. He said it was ironic that while coal-gasification plants were being closed in New Zealand, there was very active research and development of coal-gas-ification processes over - seas. . “New technology being developed promises to improve economics and efficiency of conversion of coal to gas, and should be well developed by the time there is again interest in New Zealand in coal as a sourceof gas,” Dr Stewart said. Waikato despoils were conveniently sited for feeding as into the existing distribution system, but this resource would be rapidly depleted if required as a substantial replacement for Maui gas. There would also be competition for the coal’s use for electricity generation. South Island lignite deposits could be a longsource of gas, but were well away from the existing natural-gas pipeline system and there was likely to be competition to use ’it for liquid-fuels production. The editor of “Energywatch,” Mrs Molly Melhuis, told the conference that if the industry set its sights on coal as a source of gas beyond Maui, it would have to grow bigger.

But if biomass was to be an important gas source, the industry would have to be more careful about how much reticulation it embarked on and whom it sold gas to long-term.