Coal pollution mitigation Since air is mostly nitrogen, combustion of coal often leads to production of nitrogen oxides. Sulfur dioxide and nitrogen oxides are primary causes of acid rain. For many years--before greenhouse gasses were widely understood to be a threat-- it was thought that these by-products were the only drawback to using coal. These by-products are still a problem, but they have been greatly diminished in most advanced countries due to clean air regulations. It is possible to remove most of the sulfur dioxide (SO), nitrogen oxides (NO), and particulate matter (PM) emissions from the coal-burning process. For example, various techniques are
Ontario electricity policy of carbon dioxide, 0.05 kg of sulfur dioxide and 0.8 kg of nitrogen oxides (NO) per megawatt-hour of energy generated. Compared with coal, natural gas generates about half as much carbon dioxide, one-third of the nitrogen oxides, and one one-hundredth of the sulfur oxides. Natural gas is most commonly used for heating applications in homes and businesses but natural gas-fired power generation is also a significant component of the power supply mix, accounting for 8% of Ontario's power generation capacity, with 102 natural gas generating stations. This capacity is set to increase from 5,103 MW to 9,300 MW by 2010.