Board To Use Surplus Power From Company

Press, Volume CVI, Issue 31075, 2 June 1966, Page 14

Board To Use Surplus Power From Company

Agreement has been reached between the Central Canterbury Electric Power Board and Kempthorne, Prosser and Company for the firm to supply the board with surplus power from a steam generating unit to be installed as part of the company’s contact sulphuric acid plant now being built at Hornby.

The agreement, which has the approval of the New Zealand Electricity Department, provides for the board to supply the company with power in the normal way, and for the company to “export” its own power at times when it is needed by the board.

Details of the scheme, which fit into the company’s £750,000 development at Hornby, were announced yesterday by the company’s works superintendent, Mr P. M. Roberts, of Auckland, the Christchurch business manager of the company, Mr G. A. Claridge, and the board’s engineer - manager (Mr S. E. Slatter). Mr Roberts explained that heat generated by the process would be conserved and collected to drive a steam turbine and generator, which would produce 3300 kw, more than enough for the company. The company would be able to supply the board with up to 1500 kw.

It was expected that power would be available to the board throughout the day, and that a “substantial” amount of power would be surplus between 5 p.m. and 6 p.m., one of the board's peak demand periods. “It is clear that large amounts of power should not be wasted, and if a surplus is available from various private sources, it could make a valuable contribution to the national supply,” said Mr Roberts. He mentioned

six other fertiliser works that were feeding power into the grid, and said that their combined generating capacity was 16,000 kw. Mr Slatter said the arrangement was an attractive one economically for the board, which had undertaken to set its “draw” from the company on the basis of the board's load factor. The supply would not be used just to relieve peak demands. The surplus power would be delivered at 11,000 volts, very suitable to the board, and the two systems would be interlinked, with automatic control, Mr Slatter said. Expansion now taking place at the company’s Hornby works would involve expenditure of between £750,000 and £BOO,OOO this year, said Mr Roberts.

In addition to the sulphuric acid plant, there would be extensions to the grinding plant and a new thing for New Zealand would be the plant for “scrubbing” the waste gas from superphosphate manufacture. The acid plant, though it would be similar to others installed in New Zealand fertiliser works since the war, would have novel features. There would be only three-

quarters the waste gas produced by other plants, and a £25,000 installation would reduce the amount of acid mist that could be emitted. This had been provided by arrangement with the Paparua County Council and the Health Department because the height of the new stack would be limited to 138 ft to meet approach line restrictions for the Christchurch airport and Wigram. Allowance would be made for a 40 per cent increase in the production of acid, which had hitherto been a bottleneck in making fertiliser. Mr Claridge said that the present Hornby capacity was 180,000 tons of fertiliser a year. The new plant, initially, would have an output of 280,000 tons. Surplus acid had a ready outlet to freezing works, and other industries. Mr Roberts added that the steam plant would operate at the highest pressure in the South Island, 4501 b to the square inch, and that the furnace would bum liquified sulphur as fuel. The new plant is due to come into production by midNovember. but this date is now qualified by unforseen effects of the British seamen’s strike.