Rio restarts shut capacity at NZ aluminium plant

LONDON, Oct 8 (Reuters) - Rio Tinto Ltd/Plc said it has restarted idled production at its Tiwai Point aluminium smelter in New Zealand after power supplies improved. Production at the 350,000 tonnes a year plant was cut by 11 percent in May to conserve electricity. "The recovery in the New Zealand power system last week has enabled us to gradually restart idled capacity," a spokesman said on Wednesday. "We're working towards full production in a reasonably short period," he added, without elaborating. The reduction in power began in early May and intensifed around the middle of that month. Low rainfall had pushed the levels of lakes used for hydro-electric generation in New Zealand to a level of water storage below which authorities look at possible conservation measures. About two thirds of the country's electricity is generated by hydro plants. Rio's smelter uses around 15 percent of New Zealand's total generated electricity.