Unaccounted for Energy (UFE) Calculations

Unaccounted for Energy (UFE) is calculated by comparing the known system load to the sum of all market participant estimates from the estimation, aggregation, and loss adjustment processes. Because the market participant estimates will never perfectly match the system load, these estimates are fine-tuned by allocating a portion of the total UFE to each estimate. Allocation methods differ, but in general each market participant is allocated a portion of the system UFE for each hour based on the ratio of that particular estimate's load in that hour to the total of all estimated loads in that hour. This process forces the total of all estimates to match the system load. Some markets use different UFE allocation methods, including differential allocation of UFE to interval metered loads apart from profiled loads, and adjusting the profile methodologies to minimize UFE where possible.

UFE calculations are performed as part of the settlement calculation process, and can be performed using the Measuring Component Set Calculation Rule settlement calculation rule defined in a Bulk Settlement Calculation Group executed via the Measuring Component Set Calculation (D1-MCSCA) batch process.

For smaller markets, UFE calculations can be performed using a chained sequence of Array Math and Vector and Service Quantity Math settlement calculation rules. At a basic level, this sequence looks like this:

1. Sum the market participant load from aggregation results (using Array Math)
2. Subtract the market participant load from the system load to derive the total UFE for the calculation period (using Vector and Service Quantity Math)
3. Allocate the total UFE to the various market participants as appropriate (using Array Math)