SEOUL Korea Western Power Co Ltd (WP) bought 70,000 tonnes of Indonesian sub-bituminous coal with net calorific value between 4,700 and 5,000 for loading between September and October via a spot tender, a source from the utility said on Friday. The utility had initially sought to buy 140,000 tonnes of coal via two tenders but decided not to pursue one due to lack of bidders. The utility declined to disclose the price and supplier information.   * Note: The shipment will arrive at the Taean port.