A PC-based meter-to-bill interface for a time-of-use tariff

When Eskom introduced the concept of a time-of-use (TOU) tariff during 1990, it became apparent that the existing billing system would not be able to cope with the complexity of a TOU tariff. The TOU tariff for larger customers, required that half-hourly kWh and kVArh readings, output from the TOU meters, were input to the billing system. These readings needed to be automatically retrieved from the meter, either locally using a handheld unit, or remotely via an online system, and automatically downloaded into the billing system. Since Eskom had not standardised on one type of TOU meter, the billing system needed to interface with a variety of different meter output structures. The author discusses: the meter and billing requirements for the TOU tariff; the constraints of the existing billing system; the advantages and disadvantages of the different billing system solutions; the features of the meter-to-bill interface system; and the impact of the system on the finance, marketing and metering personnel