A planned $3.4 billion coal-fired power plant in Dubai instead will be converted to use natural gas, the sheikhdom announced, amid the United Arab Emirates’ wider pledge to have net-zero carbon emissions by 2050. The announcement Thursday came in a statement quoting Sheikh Ahmed bin Saeed Al Maktoum, the chairman of the Dubai Supreme Council of Energy and CEO of the group owning the long-haul carrier Emirates. The statement offered no details on how much the conversion would cost, nor how that would affect the plant’s planned time to come online in the energy-hungry sheikhdom. The plant also w…