A performance study of PEMS applied to the Hsinta power station of Taipower

Predictive emission monitoring systems (PEMS) have been shown to be a promising technology for calculating the emissions from gas-fired stationary sources. One of the first demonstration PEMS in Taiwan was installed and operated successfully at the Hsinta power plant of the Taiwan Power Company (Taipower) in 2000. To improve the accuracy of this PEMS model, further studies were conducted at the same combined cycle gas turbine (CCGT) unit #1 of the Hsinta power plant. To optimize the NOX PEMS model, several functions were progressively developed including a log model, a one-level linear model, a three-level linear model, a 15-variable linear model, and a 15-variable with start-up mode model. The latter gave the relative accuracies (RA) and correlation coefficients between PEMS and a continuous emission monitoring system (CEMS) in the range of 3.38–14.77% and 0.955–0.989, respectively, which fulfill the criteria of the USEPA draft on PEMS performance specifications. Similarly, this model demonstrated RAs for low, medium, high level, and a three-level average less than 20% which meet CEMS requirements set out by Taiwan EPA.