Click to see subtopics:When viewing production data and when using that data to generate forecasts of future production, it is critical that the method used to calculate the rates be known, understood, and used properly. Four commonly used terms used in this regard are "operated-day rate" (op-day), "calendar-day rate" (cal-day), "time on-production", and "load factor".
The term "injection" can be substituted in all the definitions below where "production" is used.
Operated-day rate
Operated-day rate is defined as the volume of fluid produced or forecast over a period of time divided by the actual on-time during the period in days. For example, if a well produced 300 barrels of oil in a 30 day month, but was only actually producing for 15 days, then:
Operated-Day Rate = 300 Bbls / 15 days = 20 Bbls / day
Calendar-day rate
Calendar-day rate is defined as the volume of fluid produced or forecast over a period of time divided by the number of days in the period, regardless of actual on-time. For example, if a well produced 300 barrels of oil in a 30-day month, but was only actually producing for 15 days, then:
Calendar-Day Rate = 300 Bbls / 30 days = 10 Bbls / day
Time on-production
Time on-production is defined as the period of time a well is actually producing. It is typically expressed in hours or days.
15/30 * 100 = 50%
Uptime factor
Uptime factor is the ratio of the total time during which a well is operational or producing during a period of time. For example, if an uptime factor of 90% is used, the well is on the 90% of the time. This metric considers all possible outages, both scheduled and unscheduled, for a more complete representation of the amount of time a well is up.