Zambia has revised upwards planned spending on new power stations and upgrades to meet increasing electricity demand at its vast copper mines, a senior industry official said. State power utility Zesco required $1.2 billion - up from an initial target of $720 million budget last year - and was in talks with Iran's Farab International and China's Sinohydro on construction of the 750 megawatt Kafue Gorge Lower project and the 120 MW Itezhi-Tezhi power project, the official said, reports Reuters.