How do the 2026 and 2027 electricity increases change solar payback in South Africa?

Answer first: Tariff increases are the strongest tailwind solar has in South Africa. Your installed price is locked on the day you sign; the rand value of every kWh you no longer buy climbs every April (Eskom direct) or July (municipal). Model payback at today’s tariff first, then add the published increases as a separate line — never the other way round. Related: electricity tariffs 2026 · solar payback · metro tariffs.

The published increases, in one table

Sources: NERSA media statement (March 2026); NERSA Eskom retail tariff Reasons for Decision (average Eskom price 240.28 c/kWh for 2026/27 on allowable revenue of R382 854 million); NERSA RAB re-determination statement (February 2026), which phases R54.7 billion of additional allowable revenue into 2026/27 and 2027/28 after the High Court ruling; EWN (4 September 2026) on the 2027/28 consultation and the R419.4 billion allowable revenue already approved for that year.

Municipal customers feel these numbers through their metro. NERSA approves the bulk increase; each metro then files its own retail tariff. Tshwane landed at 8.8% and eThekwini at 9% for 2026/27 — our tariff desk keeps the per-metro rates and the NERSA decisions side by side.

Why a fixed system price plus rising tariffs equals faster payback

Payback is the installed price divided by the yearly rand saving. The installed price never changes after you pay. The yearly saving is the kWh you self-consume multiplied by the tariff you would otherwise pay for those kWh. When the tariff rises, the saving rises with it, and the same system pays itself off sooner.

Take a household that self-consumes 300 kWh of solar a month and pays about R4.00/kWh incl. VAT on its top block — inside the R3.30–R4.70 band most 2026/27 metro households sit in. That is a R1 200/month saving, R14 400 a year. Apply the 9.01% municipal increase and the same 300 kWh are worth about R4.36 each, R1 308/month. If the proposed 8.84% for July 2027 lands, the value rises to about R4.75/kWh, roughly R1 424/month. Two increases compound to about 18.6% more saving from exactly the same panels.

The arithmetic is ours; the percentages are NERSA’s. Swap in your own top-block rate from your municipal account or prepaid slip and your own monthly self-use figure from the inverter app.

What that does to a real quote

A fully installed 5 kW hybrid with a 5–10 kWh lithium battery is typically quoted at about R72 000 to R120 000 in 2026 (5 kW cost desk). At a flat R14 400 a year, a R96 000 midpoint quote pays back in about 6.7 years. Because today’s municipal rate already includes the July 2026 increase, the next published step is the proposed 8.84% from July 2027. Put that into year two, hold tariffs flat afterwards, and the same quote breaks even in about 6.2 years instead of 6.7. Every further increase after 2027 pulls break-even closer again.

That is why we tell readers to read payback in two lines. Line one: today’s tariff, no escalation — the floor. Line two: published increases only. Anything beyond the published numbers is the installer’s forecast, and you should see it labelled as such.

Self-use captures the increase; export captures far less

Increases apply to the kWh you buy. Export credits follow a separate schedule. In Cape Town the 2026/27 residential feed-in rate is 107.98 c/kWh excl. VAT (124.18 c incl.), plus a 25 c/kWh SSEG incentive (City of Cape Town 2026/27 tariff Annexure 6). Compare that to a top-block import price near R4: every kWh you export earns roughly a third of what it saves when you use it at home.

So the tariff tailwind rewards one habit above all: move loads into daylight. Run the geyser on a midday timer (smart geyser timers), the pool pump in sun hours (pool timer), and the dishwasher and washing machine after breakfast (laundry and dishwasher). Each shifted kWh rides the full increase. More on the split: export credit vs self-use in rand.

Fixed charges rise too — and solar does not touch them

Metros raise their fixed service, network and capacity charges in the same July cycle. Solar cuts the energy part of the bill, not the fixed part. A household that halves its grid kWh still sees the fixed line climb. Build that into your expectations: the bill falls, the fixed charge stays, and the saving lives in the energy line. See municipal fixed charges with solar and why the bill is still high after solar.

Batteries: increases make evening kWh worth more

A battery earns by moving surplus midday solar into the evening, when you would otherwise buy at the full rate. Higher tariffs lift that evening value one-for-one. Price batteries in rand per usable kWh and compare against the evening kWh you buy today. One dated example from a named distributor: ACDC Dynamics lists the BlueNova SBB MKII (BN52V-314-16K, 16 kWh nominal, 48 V-class) at a special net price of R37 341.95 incl. VAT against a R46 008 excl. list price, showing out of stock at all five branches on 27 October 2026 (ACDC Dynamics listing BN52V-314-16K/SBB-MK2). BlueNova’s manual rates it at 12 861 Wh usable at its recommended 80% DoD and ≥8 000 cycles at that depth (BlueNova SBB MKII user manual v1.2) — about R2 900 per usable kWh at that price. Line that up against Solar MD, Pylontech, Hubble, Freedom Won and other locally supported 48 V packs on the same denominator: sticker kWh vs usable · batteries guide.

Should you wait or buy now?

Buy now if your quote passes the two-line test at today’s tariff. Waiting a year means paying the 2026/27 rate on every kWh in the meantime and facing whatever 2027/28 brings, while hardware prices for panels and inverters move far less in a year than the tariff does. The rand you do not save this year does not come back.

Waiting makes sense only when you are about to change something big: a move, a roof replacement, a heat pump that reshapes your load (heat pump before more PV), or an EV that adds evening kWh. Size for the house you will live in next year.

How to use the increase when you negotiate

• Ask every installer for monthly self-consumption in kWh and the exact tariff used to value it.
• Ask for payback at today’s tariff and, separately, with only the NERSA-published increases.
• Reject quotes that value exported kWh at the import rate — how to read a solar quote.
• Compare cash and finance side by side; at prime 10.75% since 25 September 2026 (Absa financial indices), interest eats part of the tariff tailwind — solar on a home loan.
• Run the quote through our check a quote flow before you sign.

Bottom line

NERSA’s 8.76% and 9.01% for 2026/27 are approved, and 8.83% / 8.84% for 2027/28 is on the table. Every one of those points raises the value of the solar kWh you use yourself. Lock the system price, push loads into daylight, keep exports small, and the increases do the rest of the payback work for you.

Quick questions

How much did electricity go up in 2026?

NERSA approved an average 8.76% for Eskom direct customers from 1 April 2026 and 9.01% for municipalities’ bulk purchases from 1 July 2026. Metros then set their own retail increases.

What is the 2027/28 Eskom increase?

Eskom’s proposed average increase for 2027/28 is 8.83% for direct customers from 1 April 2027 and 8.84% for municipalities from 1 July 2027. NERSA gazetted it for public comment in September 2026; it is a proposal until NERSA rules.

Do tariff increases shorten solar payback?

Yes. Your system price is fixed on the day you pay, while every kWh you stop buying gets more expensive each year. The saving grows and payback comes forward.

Do increases help exported kWh as much?

No. Export credits are set separately and sit far below import rates. Self-use captures the full increase; export captures only what your metro sets for feed-in.