2 12.9% 3 2.6% >3 0.3 % The future availability quoted by PWC does not seem to be based in any significant science. To demonstrate the high levels of variability actually experienced the actual 201213 availability for Channel Island is compared to the predicted 201314 availability in the following table: Table 5.2: Channel Island Machines Actual vs. Predicted Availability Machine 20122013 20132014 Actual Availability Predicted availability Unit 1 GE 6 Combustion Turbine (gas or 98.1% 92% diesel) 31.6 MW capacity Unit 2 GE 6 Combustion Turbine (gas or 0.0% 92% diesel) 31.6 MW capacity Unit 3 GE 6 Combustion Turbine (gas or 95.6% 92% diesel) 31.6 MW capacity Unit 4 GE Frame 6 Combustion Turbine (gas or 99.4% 92% diesel) 31.6 MW capacity Unit 5 GE Frame 6 Combustion Turbine (gas or 85.4% 92% diesel) 31.6 MW capacity Unit 6 Mitsubishi Steam Turbine (waste heat) 98.8% 92% 32 MW capacity Unit 7 GE LM6000 Combustion Turbine (gas or 85.1% 92% diesel) 36 MW capacity Unit 8 Trent 60 Combustion Turbine (gas or 87.1% 92% diesel) 42 MW capacity Unit 9 Trent 60 Combustion Turbine (gas or 66.5% 92% diesel) 42 MW capacity The historic availability values for PWC machines are highly volatile, with no discernible pattern. Typically machine availability should follow one of three basic patterns: increasing availability for relatively new plant; constant availability for mid-life plant; or reducing availability for end of life plant. One possible explanation for the PWC machines failing to follow one of these patterns is that the mean time between failures of their machines is following the expected pattern and that the mean time to repair
2 12.9% 3 2.6% >3 0.3 % The future availability quoted by PWC does not seem to be based in any significant science. To demonstrate the high levels of variability actually experienced the actual 201213 availability for Channel Island is compared to the predicted 201314 availability in the following table: Table 5.2: Channel Island Machines Actual vs. Predicted Availability Machine 20122013 Actual Availability 20132014 Predicted availability Unit 1 GE 6 Combustion Turbine (gas or diesel) 31.6 MW capacity 98.1% 92% Unit 2 GE 6 Combustion Turbine (gas or diesel) 31.6 MW capacity 0.0% 92% Unit 3 GE 6 Combustion Turbine (gas or diesel) 31.6 MW capacity 95.6% 92% Unit 4 GE Frame 6 Combustion Turbine (gas or diesel) 31.6 MW capacity 99.4% 92% Unit 5 GE Frame 6 Combustion Turbine (gas or diesel) 31.6 MW capacity 85.4% 92% Unit 6 Mitsubishi Steam Turbine (waste heat) 32 MW capacity 98.8% 92% Unit 7 GE LM6000 Combustion Turbine (gas or diesel) 36 MW capacity 85.1% 92% Unit 8 Trent 60 Combustion Turbine (gas or diesel) 42 MW capacity 87.1% 92% Unit 9 Trent 60 Combustion Turbine (gas or diesel) 42 MW capacity 66.5% 92% The historic availability values for PWC machines are highly volatile, with no discernible pattern. Typically machine availability should follow one of three basic patterns: increasing availability for relatively new plant; constant availability for mid-life plant; or reducing availability for end of life plant. One possible explanation for the PWC machines failing to follow one of these patterns is that the mean time between failures of their machines is following the expected pattern and that the mean time to repair
UC-PSR-1213.docx