Ekurhuleni Tariff C 2026/27: Demand Charges Up 33%, and Why Tariff E Now Pays

On 1 July 2026, the City of Ekurhuleni's new electricity tariffs took effect. For most customers the increase was in line with the national guideline. For businesses still billed on Tariff C, it was not. The low-season demand charge on low-voltage Tariff C went from R242 to R321 per kVA, an increase of 33%.

Tariff C is a legacy bulk tariff. The City has closed it to new customers and connects new bulk supplies on Tariff E, a time-of-use tariff with a far lower demand charge. If your site is still on Tariff C, the case for moving has never been stronger, and it does not depend on installing anything.

What changed on Ekurhuleni Tariff C for 2026/27

Last year, low-voltage Tariff C charged one demand rate all year: R242 per kVA. From 1 July 2026 the demand charge is split by season, and both seasons went up. The bigger increase landed on the longer season.

• Demand charge, low season (September to May): R242 to R321 per kVA, up 33%. This rate now applies nine months of the year.
• Demand charge, high season (June to August): R242 to R268 per kVA, up 11%.
• Basic charge, network access charge and energy charges: each up about 9%. The energy rate is now R5.03/kWh in winter and R2.47/kWh in summer.

All figures are for Tariff C at 230/400 V and exclude VAT. They come from the City's own tariff schedules: the 2026/27 Schedule 2 electricity tariffs and the 2025/26 Schedule 2 (amended).

Why Tariff C is a legacy tariff

Ekurhuleni's tariff schedule is explicit: Tariff C is available to existing Tariff C customers only, and no new customers are allowed onto it (apart from those choosing its off-peak demand option). New bulk supplies with a capacity above 25 kVA and a network access charge below 1 MVA are offered Tariff E instead.

The structure shows its age in three ways:

• It bills demand in every hour. Tariff C charges on the highest demand registered in the month, including nights and weekends. Tariff E ignores demand set in off-peak hours.
• It prices energy flat. Tariff C charges the same rate per kWh at 02:00 as at 18:00 within a season. There is no reward for moving load to cheaper hours.
• Its demand charge is the highest in the schedule for its size. At R268 to R321 per kVA, Tariff C costs 56% to 87% more per kVA of demand than Tariff E.

The City's other large-business tariffs, D, E and J, all price energy by time of use. Tariff C is the exception, and the 2026/27 increase widened the gap.

Tariff C vs Tariff E: the side-by-side comparison

Here is how the two tariffs compare for a low-voltage (230/400 V) supply from 1 July 2026, excluding VAT:

• Demand charge: Tariff C R268 (high season) and R321 (low season) per kVA; Tariff E R172 per kVA in both seasons.
• Demand counted: Tariff C all hours; Tariff E peak and standard hours only.
• Network access charge: Tariff C R108 per kVA; Tariff E R115 per kVA. This is the one line where Tariff E is slightly higher.
• Energy: Tariff C flat by season, R5.03/kWh in winter and R2.47/kWh in summer; Tariff E time-of-use, from about R1.95/kWh off-peak to R11.85/kWh in the winter peak.

Tariff E is not cheaper on every line. Its winter peak energy rate is more than double Tariff C's flat winter rate, so a site that runs heavily through the evening peak gives some of the demand saving back. That is why the comparison has to be run on the site's actual load profile, not on headline rates.

What the difference looks like on a year of bills

To show the scale, take an illustrative low-voltage site with a 400 kVA maximum demand, running a day shift on weekdays and a 25% base load overnight and at weekends, about 1.7 GWh a year.

• On Tariff C: about R7.3 million a year, of which roughly R2.0 million is demand and network access charges.
• On Tariff E: about R6.5 million a year, with demand and network access charges of roughly R1.4 million.

The difference is about R780,000 a year, or 11% of the bill, before a single panel or battery is installed. Most of the saving comes from the demand charge; the energy cost is close to level because a day-shift site uses little peak-hour power.

This is not only a model. We have run the same comparison for multiple Tariff C sites across Ekurhuleni, and in every case moving to Tariff E came out cheaper.

Why time-of-use beats a flat rate

Moving to Tariff E cuts the demand charge. It also opens a second saving that Tariff C cannot offer: time-of-use arbitrage.

On a time-of-use tariff, the same kWh costs different amounts at different times of day. On Ekurhuleni Tariff E, energy costs about R2/kWh off-peak and up to R11.85/kWh in the winter peak. A battery can charge when power is cheap and discharge through the peak windows, so the site buys the same energy at a lower average price. Shifting flexible loads such as pumps, compressors, chillers and charging away from peak hours does the same thing without storage.

On Tariff C, none of this works. With one flat energy rate per season, there is no price gap to trade, and a battery can only earn its keep by trimming the monthly demand peak.

This is why the tariff decision comes before the generation decision. A battery energy storage system sized for Tariff E earns from arbitrage and demand reduction together. The same battery on Tariff C earns from one of them.

Who can move from Tariff C to Tariff E

• Supply size: Tariff E is available for bulk supplies with a capacity above 25 kVA and a network access charge below 1 MVA. Larger sites qualify for Tariff D instead.
• Timing: a tariff change takes effect from the first day of the next billing cycle, and a move away from Tariff C is not subject to the usual 12-month waiting period.
• Metering: Tariff E needs a time-of-use meter. Where the existing meter has to be changed, that cost is for the customer's account.
• One-way door: Tariff C is closed to new customers, so model the move on your real load profile before you apply.

How Phoenix Energy approaches it

Every site we work on starts with the bill, not the roof. We check the tariff first, because it is the only saving that needs no capital. Then we look at energy optimisation: efficiency, demand management and load shifting against the new tariff. Only then do we size solar and storage, because the right system on Tariff E is not the right system on Tariff C.

For a Tariff C site, that means we take 12 months of bills and, where available, interval data, run them through both tariffs, and tell you whether the change is possible, what it saves and how it changes the case for a battery or solar.

Sources

• City of Ekurhuleni, Schedule 2: Supply of Electricity Tariffs for the 2026/2027 Financial Year.
• City of Ekurhuleni, Schedule 2: Supply of Electricity Tariffs for the 2025/2026 Financial Year (amended).