...S&P Global Ratings affirmed its 'A' issuer credit rating on East Kentucky Power Cooperative Inc. (EKPC). The outlook is stable. The EKPC is a generation and transmission (G&T) cooperative. Its 16-member distribution cooperatives serve more than 537,000 retail customers in 87 of Kentucky's 120 counties. In 2017, the cooperative produced 7,564 gigawatt hours (GWh) or 58% of the 13,085 GWh it sold. Although energy sales have remained within a narrow band, self-production continues to fall, declining from 80% in 2014, 86% in 2012, and 91% in 2011. The variations reflect planned and unplanned outages, and opportunities for market purchases from resources with lower variable costs than the utility's own plant. The EKPC reported $862 million of fiscal 2017 operating revenues and almost $3 billion of debt at fiscal year-end (Dec. 31). In 2017, it was among the 10 largest G&T cooperatives in the U.S. as measured by member energy sales. The rating reflects what we consider the following credit strengths:...