The City of Windhoek in Namibia makes use of a wide variety of metering options for its customer base to fulfill certain requirements and take advantage of the various metering technologies. The function of the metering installation is to meter the consumption and, as applicable, the demand of the consumer as accurately as possible. To make it a purposeful exercise, the customer must also be billed and the monies due recovered to complete the cycle.

The metering systems as used by the City of Windhoek are broadly divided into two categories – prepayment and conventional metering. Prepayment metering’s inherent advantages of payment before use and the supporting tariff structure in use at the City of Windhoek promotes this technology for all income groups.

A recent inspection carried out on 432 prepayment meters which had been identified as candidates for possible tampering, based on predetermined thresholds, resulted in 69 cases being identified. There were a further 81 cases of the meters being broken, but still able to supply power. This represents less than 1% of prepayment meters being tampered of the total prepayment meter count of 20,000 at the time of carrying out the inspections.

The City of Windhoek uses the all-in-one type of prepayment meter in most instances. No tampering problems have yet been experienced with the 400 split type prepayment meters installed at selected locations in Windhoek. It is therefore evident that the rate of meter tampering is limited at this time.

PREPAYMENT IS POPULAR

The popularity of prepayment meters has been constantly on the increase over the last five years, at 7% to 10% of the total prepayment meter count. One of the main reasons for this is the tariff structure, which favours users with lower consumption values. Once the Regional Electricity Distributor (RED) comes into existence later in the year, the drive will be to revise the tariff structures to ensure that more customers make use of – and even convert to – prepayment meters, to lower the dependency on meter readers and the human errors they may make.

For the purposes of buying power, and especially for the lower income groups that buy power frequently, the City of Windhoek provides 24-hour automatic vending machines (AVMs) at three locations in Windhoek. It is possible to purchase power from the cashiers at five offices of the City of Windhoek as well. However, complaints were regularly received from residents that indicated their dissatisfaction at the inconvenience involved in visiting these limited vending locations.

A third party vendor was appointed by the City of Windhoek at the end of 2003 to extend the number of retail outlets in Windhoek to include shops and 24-hour convenience stores. The sales ratio between the new private company and the City of Windhoek currently stands at 67% to 33% in favour of the private vending company. It thus clearly illustrates that a convenient solution is regarded very positively by the customer base. The volumes of transactions have also increased due to the more convenient sale point distribution.

OTHER VENDING OPTIONS

We are also considering other vending options, such as making use of Internet and SMS vending. However, we do not expect the introduction of these options to increase sales, as the consumers who dominate the prepayment market at this time are unlikely to possess the infrastructure required to make use of these services.

Additional problems that surfaced were mainly attributed to the server configuration in use, and the ever-increasing volumes of prepayment transactions only handled on an on-line basis at the City of Windhoek. To solve this, the City purchased a full dedicated server set-up with multiple hard drives and simple plug and play change-over for failing parts. The unit purchased has alleviated almost all the problems associated with hardware at a cost of N$125,000 (US$21,000) compared to total sales of approximately N$50 million (US$8.3 million) per year. This greatly assisted with building the confidence in the system of both the customer base and the third party vendor.

Other meter types in use by the City of Windhoek are single and three phase conventional meters, preferred for loads up to 1 x 80A or 3 x 80A respectively. There are approximately 24,000 of these meters currently in use, and growth is slow at 2.5% a year. Billing is done based on circuit breaker size, and the tariff is more advantageous for higher consumption values. Inherently these types of meter create a revenue collection problem, in that accounts are only paid after power is consumed and there is no guarantee that monies due will be recovered. Illustrating this is the fact that the City of Windhoek currently has an outstanding electricity services debtors book of close to N$78 million (US$12.9 million) of which 39% has been outstanding for 90 days or longer.

Maximum demand kWh meters are typically used for the larger consumers – currently amounting to 597. The meters at the City of Windhoek in this category include both electromechanical and the newer generation electronic meters. Problems with the maximum demand kWh meters have increased substantially with the advent of the electronic meters – problems including wrong programming and regular breakdowns of some of the meters. The breakdown types differ from manufacturer to manufacturer, and in some instances result in data loss.

As these meters measure the energy used by large consumers, a faulty meter that persists for up to two or three months before being discovered results in back charges of millions that can be very hard to recover. It therefore becomes mandatory to have a remote metering system in place with these meter types, to ensure that readings remain consistent, that problems are identified early and that meter reader errors are avoided. With smaller installation amounts of this type, personal monthly inspections could also identify possible problems. It is important that the personnel doing the readings or inspections are technically able to detect problems, as well as being able to intelligently evaluate each installation by comparing with previous readings and the like.

METERING AUDITS

The City of Windhoek is currently busy with an audit of all maximum demand kWh metering installations. The cost of the work done by the auditing consultant amounts to approximately N$350,000 (US$59,000), but losses identified for which claims have already been made against clients amount to over N$2 million (US$340,000), and the recoverable amount may increase as the project draws to an end. The identification and back charge estimates seem to be the simple part of the work, as tough resistance is experienced on the part of customers when they are faced with a bill for many times their usual monthly consumption. We anticipate that the municipal regulations will again be tested in court during the duration of this auditing project. Similar contested cases have, however, been decided in favour of the local authorities.

A major point identified during the auditing project was to ensure that drawings and other records and documentation for metering installations are up to date and still relevant. Manual tracing of wires results in human errors that can make the inspections irrelevant and the inspectors unsure of their findings at a later date.

In the future RED scenario, the immediate plan will be to make use of the services currently offered by the City of Windhoek Finance Department to read the conventional meters still installed in the field by means of the appointed meter reader corps, to avoid double costs and identify the future direction of meter types to be used before a possible own meter reader corps is set up. The same department will continue to be employed to issue billing statements monthly, as they currently do under a service level agreement.