2. Load Forecast Scenarios
In D.04-01-050, we requested a number of specific long-term load-forecast scenarios, which we repeat here and offer further guidance.
2.1. Load Forecast Scenario Specification
IOUs are required to develop and submit the following scenarios:
CEC-IEPR Case - Base Case. Representatives of the three utilities and the CEC have met and exchanged information regarding the base assumptions upon which to develop the base-case scenario, including forecast growth rates specific to each utility's service area.
Alternative Base Case. This is an optional variant of the CEC-IEPR load forecast substituting the utility's own load and growth assumptions for those provided by the CEC. The utilities should explain how their alternative base case forecasts are different from the CEC forecasts.
High Load Case (95th Percentile). While there are difficult cost implications for customers if forecasted load fails to appear, power shortages are more likely if load growth exceeds expectations. This load forecast should be seen as an extreme high-growth case wherein load growth is substantially higher than the base forecast.
Community Choice Aggregation (CCA). In preparing a load forecast scenario including a community choice program, the CCA should be evaluated assuming an initial load migration of 5% in 2005, increasing one percentage point annually to 15% over ten years.
Core/Noncore Market Structure. In D.04-01-050, we required the utilities to include core/non-core as one planning scenario in their long-term scenarios. These load scenarios should be seen as off-takes from the base-case or alternative base case forecasts. In preparing load scenarios including a core/noncore market structure, the utilities should use the combinations of the following assumptions to produce a total of 16 core/noncore forecast scenarios:
· Eligibility:
¬ All customers with a minimum peak demand of 500 kW and above.
¬ All customers with a demand of 200 kW and above.
¬ Allow individual customers with multiple meters/accounts to aggregate their own load up to the 500 kW threshold.
¬ Allow aggregation of non-residential load by energy service providers to combined loads of 500 kW and above.
· All eligible customers choose to switch suppliers.
¬ All eligible customers leave at once.
¬ All eligible customers leave over a five-year period with equal percentages in each year.
· Start date:
¬ 2006
¬ 2009
The utilities also should estimate the amount of individual customer load between 20 kW and 200 kW that could qualify for aggregation.
Other Load Forecast Cases. The Commission is interested in knowing what the utilities think are the likely possibilities for future load situations in California. Utilities should view this as an opportunity to explain to the Commission not only their preferred base case, but also their expectations about how the future could depart from their preferred base case. In each presented load scenario, present an explanation of the underlying assumptions, why that scenario is important, and the likelihood that the case will come to pass.
2.2. Planning Reserves
In each of the load forecast scenarios developed pursuant to the above instructions, IOUs are required to identify the amount of planning reserves for each year using two assumptions for planning reserve margins:
Phase-In of Resource Adequacy Requirement: D.04-01-050 concluded that the utilities should meet the 15-17% resource adequacy requirement by no later than January 1, 2008, but did not establish interim benchmarks. In their long-term procurement Plans and in the load-forecast scenarios discussed above, utilities should assume a phase in of 10% by June 1, 2005; 12% by June 1, 2006; and 14% by June 1, 2007.
Accelerated Phase-In of PRM: Pursuant to the Governor's letter to CPUC President Peevey,2 the utilities should quantify the amount of annual reserves for each load scenario based on the assumption that full resource adequacy will be achieved by June 1, 2006.
2.3. Documentation
Each of the load forecasting scenarios defined above, and others each respondent chooses to submit, should be documented in the following manner. The specific assumptions defining the scenario should be clearly specified in a narrative description. The results of each scenario should be provided in terms of ten-year annual peak loads, and 8,760 hourly loads for each of the ten years. The level of planning reserves for each of the two reserves scenarios should be identified for each of the five summer months - May through September - for all ten years. A summary table and narrative comparing all of these scenarios should be prepared. The respondents and ED/CEC staff should develop a mutually acceptable format for the detailed hourly load results.
2 Governor Arnold Schwarzenegger's April 28, 2004 letter to President Michael Peevey.
