Across North America, electronic smart meters are replacing traditional meters. These meters record consumption at frequent intervals, commonly 5 minutes, 15 minutes, or one hour, and then deliver that information to a central database where it is used to assemble customer invoices.
The advantages to utilities and regulators are clear. Interval meters allow regulators to pass time-based pricing signals on to customers, reflecting the variability in the wholesale market. For example, real-time pricing (based on the variable wholesale price) or time-of-use pricing will motivate consumers to shift consumption to preferred times when they will pay less.
For energy managers, smart meters create a new high volume source of data in addition to the monthly flow of invoices. This extra information adds complexity but can be used to improve decision making. In fact, some kind of analysis of interval readings is import for all users exposed to time-based tariffs.
ManagingEnergy handles both traditional non-interval and interval meters. For interval meters it stores both interval readings and invoice details, ongoing.
To speed up reporting, ManagingEnergy is continually aggregating new interval data into 15-minute, hourly, daily, and monthly values. When a report, dashboard, or export is called, it makes use of the most appropriate rolled-up version of the data to avoid churning through the thousands of readings originally collected by the meter.
Invoices include consumption values. When an invoice is entered, the invoiced consumption replaces the monthly aggregated value if there is one. In the event that interval data arrives after the invoice has been entered, the invoiced consumption will remain as the monthly value.
Invoiced consumption values replace monthly interval data roll-ups. When a user is working with monthly-resolution readings from an interval meter, those values are based on the invoiced amounts, where they exist, rather than monthly aggregation of the interval readings.
Where invoices are missing or have not yet been entered, the interval aggregation is used.
When invoiced periods don't match calendar months...
Utilities, when invoicing based on interval data, will normally align invoiced reading periods with calendar months. However this will not always be true. To illustrate, invoices do not match calendar months in the diagram below. Suppose Invoice B, which covers part of January and part of February, is entered after the interval data for all of February. In this case, the February portion of the Invoice B reading will replace the full month interval value on dashboards, reports and exports, even though it represents only part of the month.
Reconciling Invoiced Consumption with Interval Readings
The invoiced consumption should always match the interval readings, especially since the utility is using those readings to assemble the invoice. Nonetheless this alignment is worth confirming. It is important to understand that only the monthly roll-up is changed when an invoice is entered. The meter source data remains intact. When reconciling interval readings with invoiced consumption, ManagingEnergy goes back to the meter source data.