Govt blamed for slow start on biogas

Press, 18 October 1980, Page 23

Govt blamed for slow start on biogas

Energy reporter - Biogas production, which could be a big fuelsaver for farmers, is being held back by the Government’s failure to provide the same incentives as apply to natural gas, according to an agricultural scientist. It is believed that farmers will put pressure on the Government to extend incentives to biogas before Christmas. Dr D. Stewart, of the Invermay Agricultural Research Centre, said that incentives could “snowball” the number of biogas plants being installed on farms. Without the incentives, plants would be installed at the present “steady” rate — but only 20 plants are in use throughout New Zealand. Biogas is methane, . the same gas which is piped through natural gas pipeline in the North Island. But. whereas the North Is-, land natural gas is pro-

duced from gas reserves in Kapuni and Maui, and purified to remove other gases, biogas is produced from crops, such as maize and kale. North Islanders who want to install compressed natural gas appliances receive a 25 per cent cash grant from the Government to cpver the cost of compressors and storage cylinders. As compressors and cylinders cost about $BOOO, and another $2OOO can be added for electrical wiring and installation, the cash grant can amount to about $2500. North Islanders also receive tax write-off concessions for investment in C.N.G. plant. Natural gas is not available in the South Island, but, according to Dr Stewart, farmers believe the same incentives should apply , to biotas, as it is the same gas and can be used in the same way as natural gas. The 20 plants already

installed in New Zealand are used for a variety of purposes, ■. including fuelling cars, { heating glasshouses, and generating electricity. The economics of biogas production also make it attractive to farmers, says Dr Stewart. It can be produced at a more competitive cost than ethanql or oil from rape. According to figures Dr Stewart showed delegates at an alternative energy seminar in Christchurch, biogas could be produced at 19c a litre from either maize or kale. This compares favourably with 51.3 c a litre cost of producing ethanol from beet, and 49c a litre for making oil from rape. Premium petrol, which carries tax and profit margins above cost price, retails for 54c a litre. These figures were based on costs for crops and machinery, less the estimated value of resi-

dues which could be sold or used as animal feed. JFor instance, the crop cost of maize for biogas production was given as 13.6 c a litre, and the total cost of production as 35.7 c a litre. Residues, which could be used as high-pro-tein feed, were estimated at 16.7 a litre, giving 19c. a litre as the cost to the farmer of producing biogas. Comparable figures for ethanol, produced from beet, were: crop cost, 30.6 c a litre; total cost, 64.6 c a litre. Residues were valued at 13.3 c a litre, giving 51.3 c a litre as the cost to the farmer of producing ethanol: Dr Stewart said that biogas was a possible replacement for natural gas when the Maui and Kapuni fields ran out. If there was any doubt about New Zealand’s ability to produce enough gas for such a demand, he suggested that people look at China, which already produces as much biogas each year as the total Maui gas reserve.

Groups approached the Government IS months ago for an extension of the C.N.G. incentives to biogas, and some measures were expected in the last Budget. But the Government has not acted yet. One suggested reason is that the incentives should be seen to be working, by encouraging people to plant biogas crops, who would not have planted them otherwise.

The argument goes that many farmers already grow the crops necessary and gain valuable overseas exchange from them. That gain would have to be weighed against the potentiaT savings in New Zealand’s fuel bill by replaping fuels with