THE PRESS THURSDAY, JUNE 15, 1978. Without hot water

Press, 15 June 1978, Page 16

THE PRESS THURSDAY, JUNE 15, 1978. Without hot water

The reaction of people in Christchurch who found themselves without hot water supplies on Tuesday is understandable. Our report on the control of electricity used for water heating makes clear that there is no early solution to the problem of controlling water heating. The supply authorities face special charges for exceptional peak loads, and these additional charges are made to discourage high demands for electricity. The charges are one of the two elements in the present price structure the Electricity Division of the Ministry of Energy imposes on the supply authorities. In turn the supply authorities cut off consumers’ water heating power to keep down demand. Supply authorities would be able to meet the peak demands and pay the higher charges by passing on the cost to domestic and commercial consumers. But in the end the Electricity Division would have to decree the absolute limits of supply that are imposed by the generating system. Another hydro station the size of Benmore might meet the highest demands that consumers are likely to exert in winter: but, to enjoy the benefit of having emergency generating capacity, the consumer would almost certainly face higher charges for the base load An alternative to imposing the high peak tariff would be for the Electricity Division to advise the supply authorities when the demand is nearing the system’s capacity to generate sufficient electricity. Ripple control might then be imposed, as it is now. This would mean that the present pricing system would have to be abandoned and the costs of power generation would be apportioned to supply authorities without a special loading for exceptional demand. The onus for imposing power cuts on domestic water heating would then be on the generating authority. This might persuade power planners to recommend the building of more generating stations to meet any foreseeable demand. Because the develop-

ment of generating stations is only one among many reasons for capital expenditure it would be foolish to use too great a proportion of the country's resources for this purpose. Yet it would be equally foolish if consumers are denied electricity because the present pricing is convenient for the authorities rather than because the generating system is inadequate. Some account, however, must be taken of the present generating system under 'which additional demand in the North Island is met at great cost by using imported fuel. Solar heating has not provided a satisfactory answer to the problems of peak power load. In fact, solar heating equipment tends to emphasise the problem. On the very days when the demand for electricity is highest, the sun is not shining and an extra demand is placed on the electricity system. Special loans are now available for solar heaters but no such loans have yet been approved, not least because no solar heater yet has official Government approval. Furthermore, the cost of solar heaters is still so high that, while the country might eventually benefit from their widespread use, the individual will find it hard to recover the outlay on equipment. So far, the most promising solution offered by engineers is the building of huge tanks to store water heated by the sun — sufficiently large to store heat through cold weather. In the meantime, and so long as hydro-electric generation can be enlarged at reasonable cost, the consumers are better off financially if they are prepared to suffer the occasional inconvenience of having ripple control applied by the supply authorities. Very little enthusiasm is likely to be aroused among the majority of consumers for a sufficient increase in power charges to meet all possible demand for power. Nevertheless, temporary inconvenience will be greatly lessened if supply authorities can give reasonable notice of cuts in power.