Remote Area Power Supply Alternatives in Western Australia

The policy for remote areas included the extension of an interconnected system; centralised diesel plants in country towns; improved performance of isolated generator sets; solar thermal generating units; solar photovoltaic generating units, and wind power units.

Extension of Grid

Between 1977 and 1983 rural customers in Western Australia have been added at the rate of 1,400 per year. In the 1981/82 financial year, a staggering 4,700 km of rural extension lines were added to the distant extremes of the metropolitan grid. In 1984 the Kalgoorlie goldfields region was added, displacing 15 megawatts of SECWA diesel plant and a further 43 megawatts of privately owned plant. In 1985 Port Hedland, Cape Lambert and Dampier/Karratha will be interconnected, with the power coming from Cape Lambert power station which is fueled on indigenous north west gas. This will displace a further 30 megawatts approximately of liquid imported fuel based plant.

It is hoped that by now Western Australia will have reduced its dependance on liquid import fuels from more than 50 per cent in 1974 to less than 10 per cent of total statewide generation. The State's richest export industries will thus be buffered against oil shortages in the future. Further the Commission has decided to pipe NW gas into Canarvon Power Station and is actively engaged in research to run the major part of its remaining distillate based plant on liquid natural gas (LNG) derived from the NW gas. Optimistically, then, in the future Western Australia will have minimal dependance on the liquid imported fuels.

Centralised Plant in Country Towns

The major advantage of this is to obtain improved diversity in plant use. An example has been the expansion of the Great Southern (Esperance) grid. A load consisting of large numbers of consumers tends to vary slowly enabling the selection of optimal plant (fuel efficiency wise) for the load. Diversity considerations are the main reasons for extending local country town grids.

Changed Considerations

In 1985 a report was prepared considering the capital cost of supplying the rural extreme grid connections. It was estimated that with capital and interest rates considered each unit of electricity was costing 87c to supply. The commission was charging 12c per unit. The policy of subsidy was based on state legislation. These costs have caused SECWA to began again considering options to rural extension.

Among the options being considered are photovoltaics and windpower. The Commission has become well aware of these options because of the RAPSI (Remote Area Power Supply Investigations) research program it implemented in 1978. Up until 1985 the SECWA had spent approximately $8 M in researching renewables energy technology. This program included two solar thermal power stations, the Ansaldo at Ballajura and the Step 100 project at Meekatharra. The Meekatharra project ran successfully for eighteen months. Research data gathered on the latter project clearly indicated this type of technology would not be viable.

Australian Academy of Technological Sciences and Engineering