* Thermoelectric had been blocked on environmental grounds * Miners seen cheering decision; green groups blast OK * World No.1 copper producer Chile facing energy woes SANTIAGO, Dec 3 (Reuters) - A Chilean ministerial group lifted a suspension on energy firm Endesa's 740-megawatt Punta Alcalde coal-fired thermoelectric project, local media said on Monday, in a boon for miners in the mineral-rich north of the world's No.1 copper-producing nation. An environmental commission had