BACKGROUND

The Standard Transfer Specification (STS) is the global standard for the transfer of electricity and other utility prepayment tokens. It secures message protocol that allows information to be carried between a point-of- sale (POS) and a prepayment meter and is currently finding wide application in electricity metering and payment systems. Municipalities use the STS technology in their electricity and water utilities business to measure and charge water and electricity. The STS was first introduced in South Africa in 1993 and subsequently published by the International Electro-technical Commission as the IEC62055 series of specifications. The application of the technology is licensed through the STS Association, thus ensuring that the appropriate key-management encryption practices are applied to protect the security of the prepayment transactions of utilities.

The STS is used by over 500 utilities across the world in over 40 countries. According to STS Association, South Africa has over 10 million STS electricity prepaid meters, of which 7 million are managed by Eskom and over 3 million are managed by municipalities including metropolitans. The STS provides the facility of generating (e.g. credit transfer) tokens which can only be used by the intended meter, and furthermore in the case of credit tokens, can only be used once in that meter. Each credit token has a unique token identifier (TID) encoded into the 20 digits to prevent token replay at the meter. The TID is a 24-bit field, contained in STS compliant tokens, that identifies the date and time the token was generated.

The use of the STS standard prevents:

• Fraudulent transfer of credit resulting from hit and miss attempts at entering the correct number;
• Fraudulent generation of tokens from a stolen vending station;
• Fraudulent generation of tokens from legitimate vending stations outside of the utility's area;
• Fraudulent re-use of tokens which have already been used; and
• Tampering of legitimate tokens e.g. to change the value
  
  
  

PROBLEM STATEMENT

All prepayment meters based on STS technology will stop dispensing electricity on 24 November 2024, thus presenting a significant risk to the service levels, sales and revenue collection of all municipalities to end user customers in the electricity utilities business. The TID is referenced to a base date of 1993 and will run out of range in 2024 (known as the TID Rollover event), thus causing the prepayment meter to stop accepting new tokens.

Therefore, the prepayment meters will stop accepting new credit tokens, and will then stop dispensing electricity after the existing credits are used up. Any tokens generated after this date and utilizing the 24 digit TID, calculated on base date 1993, will be rejected by the meters as being old tokens as the TID value encoded in the token will have reset back to 0. Thus, there is a need for a proper plan and structures in place to manage this risk, thereby ensuring that municipalities perform the TID rollover for each and every prepayment meter by November 2024. This requires substantial time, effort and resource loading on the part of the municipalities, so it is imperative that the remedial action process commences as a matter of urgency.

DISCUSSION

SALGA conducted a survey on the Standard Transfer Specification (STS) prepayment meters TID rollover status quo in South African municipalities in July 2021 to gauge the progress made by municipalities on the TID rollover project towards 2024. It was found that there are 3 092 824 prepaid meters1 across the country, and only a few municipalities, mainly those based in the Western Cape, Gauteng and Kwazulu Natal, had started the process of TID rollover.

SALGA has hosted a workshop on 24 March 2022 to establish the status quo and progress made by municipalities and Eskom in rolling out the prepayment meter reset project; and to launch the SALGA dashboard for STS prepayment meter reset project. . The workshop further identified what support SALGA and its partners (AMEU, STS Association, SANEDI, Eskom, CoGTA and NT) can offer to municipalities. It became clear that there are common challenges across municipalities, and it is important for municipalities to learn from one another.