... Ratings compared the performance of 19 operating wind projects with its expectations when the ratings were assigned. There are chronic production shortfalls below base case expectations at a majority of the projects. Actual production only occasionally exceeds base case levels and generally falls between base and rating case levels. On average, actual production has been 7.8% below Fitch's base case projections and 6.1% above Fitch's rating case. Conservative Rating Case Justified: Fitch relies on energy production forecasts prepared by wind resource consultants to create its base and rating cases. Fitch's base case incorporates the wind consultants' P50 estimate ¡ the consultants' best estimate of the long-term annual level of output with a 50% chance that the result will be higher or lower. The combined stress rating case incorporates the one-year P90 (1yP90) estimate, which is the output level that has a 90% chance of being exceeded...
