What is a geyser ripple relay / load control with solar in South Africa?

Answer first: Find the load-control / ripple receiver (often near the DB or geyser isolator). Ask the electrician whether the metro still signals it, whether a contactor bypasses it, and how that sits next to any smart geyser timer or PV diverter. Pair with geyser on backup · water heating · essentials.

Why this is a South African quirk

Decades of municipal demand management left ripple receivers on countless geysers. Solar does not automatically remove them. A hybrid that “heats on surplus” while the ripple is open simply does nothing — and owners assume the plant is broken.

Coordination table

Homeowner checks

1. Label photos: ripple device, timer, geyser isolator, hybrid load contactor.
2. Ask the metro or sparky whether load control is still active on your erf.
3. Decide one “boss” schedule — usually PV surplus midday, with ripple respected where required.
4. Write the logic into the handover pack — read a quote.

Rand sketch

A 3 kW element for 1.5 sun hours is ~4.5 kWh. At 350–470 c that is roughly R16–R21 of avoided import when PV actually reaches the element. If ripple blocks those hours, you heat at night from grid or battery instead — often the expensive path — export vs self-use · TOU.

What not to do

• Do not bridge out a sealed municipal device without the registered person and metro rules.
• Do not put the geyser on backup “so ripple does not matter” without a Stage kWh budget.
• Do not run three timers that all think they own the element.

Related: geyser overload · heat pump vs geyser · CoC.

Homeowner folder to keep with the CoC

Store quote annexures, OEM manuals, serial photos, export-limit screenshots and metro reference letters together. When a future technician or buyer inherits the plant, that folder beats scattered WhatsApps — choose installer · selling with solar · warranty transfer.

Re-check fixed charges and tariff codes after any meter change so savings models stay honest — fixed charges · 2026/27 tariffs · metro tariffs hub · bill still high.

Field notes from SA handovers

At commissioning, ask the partner to demonstrate the behaviour on this page, photograph settings, and confirm NRS-listed SKUs match the invoice. Refuse non-listed gear and export promises that ignore your metro’s live PDF — red flags · NRS list · SSEG · read a quote.

Where this sits on the desk

Cross-check related cards on Answers, tariff context on metro tariffs, and hardware on batteries / panels & inverters. Use check a quote before any deposit.

Worked homeowner checklist

1. Photograph board labels, nameplates and meter face before the site visit ends.
2. Save the live metro or OEM PDF that backs any rand or rule cited on the quote.
3. Book a Stage simulation (island test) where backup behaviour matters.
4. Diary a 30-day monitoring review against the first bill after commissioning.

If numbers diverge, revisit self-use loads and fixed charges before accusing the array — monitoring · monthly savings · export vs self-use.

How ripple shows up on a hybrid monitoring app

Owners often see “surplus available” at noon while the geyser temperature flatlines. The hybrid is telling the truth about PV; the element simply is not in circuit. Toggle the metro/load-control path (via the registered person) or move diversion to a contactor the hybrid actually owns. Log three clear-sky days with timestamps before changing hardware — monitoring numbers · dongle offline.

Prepaid and TOU interactions

On prepaid meters, cold-water complaints spike when token behaviour and ripple coincide. On Cape Town-style TOU, heating in the expensive evening band because midday ripple blocked PV is a classic own-goal — prepaid · Cape Town TOU · TOU prepaid EV.

Installer handover script

1. Point at the ripple/load-control device and say whether it is still live.
2. Show the timer or dry-contact schedule in the app.
3. Run a one-hour PV-divert demo with a temperature rise you can feel.
4. Leave a one-page diagram in the CoC folder.

If the partner shrugs (“the metro thing”), treat that as a red flag for water-heating commissioning — red flags · choose installer.

Heat pump alternative path

Where ripple chronically steals midday electric heating, a heat pump on a dedicated circuit with its own schedule can outrun element-plus-ripple drama — price it against keeping LPG for mornings — heat pump vs geyser · add heat pump · water heating hub.

Stage nights vs ripple days

Do not solve a daytime ripple problem by parking the geyser permanently on the backup board. That converts every Stage into a hot-water raid on the battery you bought for lights and fridge. Prefer daytime PV windows and a lean Stage rule — Stage strategy · Stage 4 · essentials.

Questions to put on every installer WhatsApp

• Which primary PDF or metro page backs the claim you just made?
• Who registers warranties and by which calendar deadline?
• What happens to export and backup if the first SSEG pack is rejected?
• Can you show a recent CoC and labelled board photo from a similar job?

Those four questions surface more truth than a glossy kWp number — choose installer · red flags · CoC · SSEG.

Bill hygiene after commissioning

Keep three months of pre-solar bills and three months after. Annotate tariff changes, guests, pool season and EV km. Without that diary, “solar did nothing” debates go nowhere — monthly savings · bill still high · read a bill · fixed charges.

Dual-element and heat-pump hybrids

Homes with dual elements or a heat pump plus element need an even clearer control map: which device the ripple opens, which device the hybrid diverts to, and whether night-setback still makes sense. Draw it once on paper before anyone rewires — heat pump vs geyser · add heat pump · smart timer.

Worked midday diversion day

Assume 4 kW PV available after house baseload at 11:00, a 3 kW element, and ripple closed (allowed). The hybrid diverts ~3 kW for 90 minutes → ~4.5 kWh into the tank. At 400 c avoided import that is ~R18 of value, plus comfort. Same day with ripple open: those 4.5 kWh either export at a weaker credit or curtail. That single contrast is why mapping load control belongs on day-one commissioning, not after winter complaints — export vs self-use · feed-in · zero-export.

Ripple relays and solar self-use

Some metros still use ripple / load-control to switch geysers. If the relay kills the element during your best PV hours, self-use maths breaks. Ask the electrician whether the geyser contactor can be controlled by the inverter’s smart load instead of (or in addition to) ripple, within metro rules.

• Photograph the ripple receiver before changes.
• Never bypass metro load-control without written approval.
• Heat pumps may interact differently — confirm — geyser backup · water heating.

Homeowner close-out for geyser ripple relay load control solar sa

Keep OEM and metro PDFs beside this answer. Confirm Incl. VAT line items, NRS-listed SKUs where relevant, and who owns paperwork after deposit. Compare two written scopes before you pay — read a quote · choose installer · check a quote · get quotes · costs & savings · metro tariffs.

Quick questions

Does solar remove the ripple relay?

No — the municipal device can still open the geyser circuit unless reworked under rules.

Can I use a smart timer with ripple?

Yes if coordinated — one clear control hierarchy beats stacked mystery relays.

Should the geyser sit on the backup board?

Only with a deliberate Stage budget — hot water is a hungry load.

Sources & related

• Solar News 24 — smart geyser timer
• Solar News 24 — geyser on backup
• Solar News 24 — water heating hub
• Solar News 24 — essentials board