As is clear and impelling for customers, FGD plants can cut sulfur dioxide emissions by 90 percent or more. Firstly, it dramatically reduces SO2 emissions, thus avoiding the liability and large fines that may accrue. Although the process is very energy-inefficient, typically between 90% and 95% of sulfur dioxide is removed from flue gases. This not only improves the ambient air quality but also represents a further development in shaping companies' public image in our epoch as environmentally responsible entities. Most importantly, the gypsum produced in by-product form can be marketed or reused. This develops an additional revenue stream for plant operators while at the same time enhancing their environmental performance. The capital investment costs and maintenance of an FGD plant reaction are higher than those for conventional flue gas desulfurization systems. Yet, by doing so, it ensures that the operation will supply environmental returns sufficiently long into the future to make such an expenditure reasonable.