D-day for prepay meter TID rollover

The STS standard prepay meter ‘token identifier’ (TID) rollover occurs at 01h00 UTC+3 on 24 November 2024.

With the rollover at each meter a TID reset occurs and a key change is necessitated, so that previously used recharge tokens will not be accepted by the meters.

Without the key change also, the meters will stop accepting new credit tokens and will then stop dispensing electricity after existing credits are used up.

The Standard Transfer Specification (STS), first introduced in South Africa where it was developed in 1993 and subsequently published as IEC62055, is a global standard for the transfer of electricity and other utility prepayment tokens.

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It secures the message protocol that allows information to be carried between a point-of-sale and a prepayment meter.

The TID is a 24-bit field contained in STS compliant tokens that identifies the date and time of the token generation – in essence representing the number of minutes elapsed since a base date of 1 January 1993.

It is used to determine if a token has already been used in a payment meter. However, with the incrementing of the 24-bit field, at some point in time the TID value would roll over to a zero value.

To avoid this the managed rollover has been implemented, also enabling improved security and other enhancements of the STS Edition 2 specifications.

The base date also changes to 1 January 2014.

Looming TID rollover chaos?

With the STS reported to be in use by over 500 utilities in over 40 countries across the world, the STS Association has been preparing for and advising about the rollover for over four years but still meters are outstanding.

Eskom, which manages 6.9 million of the approximately 11 million STS prepay meters in South Africa, is reported to have around 2 million meters outstanding.

At the start of the week, Eskom was still urging customers to ensure their meters are updated – particularly those who have not purchased electricity for more than six months or might be using unauthorised tokens bought from criminal syndicates.

“We started our public awareness campaigns back in August 2023 and we continue to ask users to come forward so we can offer all the help we have available,” said Monde Bala, Eskom’s Group Executive for Distribution, in a statement.

Figures from the South African Local Government Association (SALGA) indicate that around 268,000 municipal managed meters also are still outstanding.

“Cut-off chaos looms”, blared a South African news headline – and with customers outstanding facing, in addition to discontinued electricity or water, the cost of a new meter, in Eskom’s case up to ZAR12,000 (US$660), utility suppliers are set to be working overtime just as the holiday season looms.

But work done, based on the timeline the next rollover is not due to take place until 2035.