California ISO - Documents By Group

Operations and maintenance cost adder review and update
As an outcome of the bidding and mitigation of commitment costs initiative (phase 2), the California ISO is initiating the first re-evaluation of the operations and maintenance cost adder used for proxy minimum load costs and default energy bids to make sure they still reflect resources’ variable operations and maintenance costs. The ISO will communicate the study methodology and resulting recommendations for updated operations and maintenance values through a stakeholder implementation forum and stakeholders will have the opportunity to provide comments. The first update to the default operations and maintenance cost adder is targeted for implementation on April 1, 2012. Re-evaluations take place every three years.
- Outcome
  On Mar 29, 2012 the ISO revised its default operations and maintenance cost adders, which represent the per-megawatt hour variable, non-fuel costs of running a generating unit at or above its minimum operating level. The ISO increased the number of adder values from two to ten to differentiate costs by technology for all generation resources participating in the market. The ISO will re-evaluate these values every three years. — Effective date: Trading day Apr 01, 2012; FERC Order: Mar 15, 2012 (ER12-806); Tariff amendment filing: Jan 13, 2012; Board of Governors approval: Dec 15, 2011
- Operations and maintenance cost adder review and update - studies