Cape Town Approved Inverter Register and Reverse Power Guide

Key Takeaways

• Since 1 October 2023, all new solar PV and/or battery systems are being treated as grid-tied and must use City-approved inverters, have professional sign-off, and be authorised before switching on.
• The City of Cape Town only accepts NRS 097-2-1 approved inverters that automatically disconnect without energising the distribution network during outages.
• Standby and off-grid configurations are no longer permitted on properties with municipal electrical connections.
• Non-feed-in installations require reverse power flow blocking to prevent any surplus energy from reaching the network.
• Systems using non-approved inverters will not be authorised, and connecting an unauthorised embedded generation system is illegal.

Mandatory Grid-Tied Classification & Register Overview

The City of Cape Town enforces strict technical standards for distributed energy resources. A critical policy shift occurred when the municipality announced that since 1 October 2023, all new solar PV and/or battery systems are being treated as grid-tied and must use City-approved inverters, have professional sign-off, and be authorised before switching on. Under this regulatory framework, the City maintains and publishes a list of NRS 097-2-1 approved inverters.

The primary regulatory instrument is the register titled TYPE TESTED INVERTERS/EQUIPMENT IN TERMS OF NRS 097-2-1 2026/06/10. Equipment not listed on this official register cannot receive municipal connection approval. The municipality has explicitly stated that systems using non-approved inverters will not be authorised. Connecting an unauthorised system is illegal.

Cessation of Standby and Off-Grid Approvals

A widespread misconception among property owners was that installing an off-grid or manual changeover standby system exempted the installation from municipal oversight. The City clarified this in its regulatory guidance: we are no longer accepting applications for standby and off-grid systems due to the risks they pose.

In its formal technical documentation, the municipality elaborated: off-grid and standby solar PV systems are no longer permitted on properties with City of Cape Town electrical connections. The underlying technical rationale focuses on safety and network integrity: inverters must adhere to these requirements to ensure the safety of residents and municipal workers, particularly regarding anti-islanding protection so that when the network goes down, the inverter switches off safely without energising the grid.

The scope of this municipal framework covers small-scale embedded generation (SSEG) systems with a generation capacity smaller than 1 mega-volt ampere (MVA). Property owners benefit from the policy that the registration and authorisation process is free.

Reverse Power Flow Blocking for Non-Feed-in Systems

For residential and commercial consumers who choose not to export surplus energy to the municipal grid, the City provides a dedicated non-feed-in compliance pathway: if you do not intend to feed into the grid, you will need to enable reverse power flow blocking. A prepayment meter is required and will be installed by us at our cost.

Reverse power flow blocking dynamically modulates inverter output based on real-time household consumption, preventing any active power from flowing back through the point of connection. When selecting this option: if you are installing a non-feed-in system (with reverse power flow blocking), you will remain on your current tariff. You will be able to connect your system from the day you receive your Commissioning Approval Letter.

In contrast, consumers intending to export power operate under different metering arrangements: if you have a feed-in system, you will need to install an Advanced Metering Infrastructure (AMI) meter at your own cost. Once commissioned, you will be placed on the SSEG tariff from the date your AMI meter is installed.