Impact of SO2 emissions cap on Phase I compliance decisions

The SO2 emissions cap provisions of impending clean air legislation will dramatically affect Phase I and Phase II compliance decisions by electric utilities. Technology-based SO2 reduction alternatives could become the keystone of most compliance strategies as utilities attempt to achieve lower and lower SO2 emission rates. Compliance with the Phase II emissions cap will require technological solutions for many utilities which must meet system-wide SO2 emission rates well below those achievable with low-sulfur eastern coals and, in many instances, western coals. The emissions cap provision, however, will also induce more scrubbing during the Phase I compliance period. The power generation dispatch capability of a hypothetical utility system was simulated to study the impacts of an SO2 emission cap on compliance strategies in Phase I. The effects of the cap were quantified for generation costs, total SO2 emissions, and effective emission rates. The results show that achieving compliance by installing state-of-the-art high SO2 removal scrubbers becomes increasingly attractive as utilities become constrained under the SO2 cap, even in Phase I