Bonneville Power Administration

Transcription

1 Risky Business Asset Management for Aging Hydro Plants Bonneville Power Administration Northwest Hydroelectric Association February 2016

2 The Federal Columbia River Power System 31 Powerplants (21 Corps, 10 Reclamation) 196 Generating Units 22,060 MW 60% of region s hydroelectric capacity 65 million+ MWh/year 2

3 Asset Age Over 30% of the assets in the FCRPS are at or exceeding their design life. Of those assets, over 60% are related to unit reliability and have direct impacts on generation. 3

4 Assessing Asset Condition The FCRPS uses the hydroamp Condition Assessment framework to assess the condition of over 5500 assets. The hydroamp guide contains specific instructions for the condition assessment of: Turbines Generators (Rotors and Stators) Excitation Systems Governors Transformers Circuit Breakers Surge Arrestors Cranes Batteries Compressed Air Systems Emergency Closure Gates and Valves Penstocks Additionally, a more generic Balance of Plant guide can be used to assess the condition of more than eighty additional components. 4

5 Projecting Condition Degradation The condition of each asset is projected over time using degradation curves derived from FCRPS and available industry data. In the chart above, the average equipment score of each plant for a given piece of equipment is plotted against the projected degradation rate. 5

6 Relating Condition to a Probability of Failure Using a combination of industry failure data as well as expert opinion elicitation, hydroamp condition is mapped to a probability of failure for each equipment type. 6

7 Calculating Risk With an understanding of condition, how it changes without intervention and how it relates to a probability of failure, risk can be forecast over time. Using Copperleaf s C55, the FCRPS forecasts the following risks and costs: Lost Generation Risk: Equipment failure may also result in longer outages and, thus, more lost generation than if replaced on a planned basis. This cost risk increases as equipment condition degrades over time. Direct Cost Risk: If equipment fails during the deferral period, intervention costs may be incrementally higher for collateral damage and planning, procurement, and scheduling inefficiencies (overtime, emergency hiring, contract premiums, etc.). This cost risk also increases as equipment condition degrades over time. Lost Efficiency Opportunity: Some equipment replacements (turbine runners, transformers and generator windings) reduce efficiency losses. Deferring replacement results in a lost opportunity to capture increased generation from higher efficiency equipment. Replacement Cost: Typically, the longer the replacement can be deferred, the lower the present value of its cost. 7

8 Optimizing Replacement Timing The Total Cost is the present value sum of replacement costs, risk costs and LEO. The cost minimum on this curve is the point at which financial risk is forecasted to begin growing faster than the benefit of investment deferral and represents the optimum time to forecast replacement to minimize lifecycle cost. 8

9 $000s Prioritizing Investment Capital Program Forecast For a given program level, the C55 Asset Analytics will fill in investment based on the cost minimization algorithm. Assets with lower deferral costs are deferred in favor of assets with higher deferral costs when a budget constraints are introduced. The chart above displays the results at a $300 million budget level from BPA s 2014 Capital Investment Review materials. 9

10 The Cost of Deferral High Deferral Cost Low Deferral Cost 10

11 Sensitivity Analysis Sensitivity analyses can help zero in on the optimal program level by analyzing both the qualitative and quantitative results. Running C55 Asset Analytics at different Capital Program levels can quickly show the impacts on the Condition, Age and Risk of assets over time. 11

12 Condition Forecast for a Given Capital Program 12

13 Condition Forecast for a Higher Capital Program 13

14 Lost Generation Risk Forecast 14

15 Non-Routine Expense Forecast 15

16 NPV of Different Capital Program Levels 16

17 Gordon Ashby