1. Introduction

A National Transmission Company (NTC) is the institution responsible for operating, maintaining and developing a country's high-voltage electricity transmission network. In South Africa, this concept is particularly important because of the restructuring of Eskom and the creation of the National Transmission Company South Africa (NTCSA) as part of electricity-market reform.

The legal framework is principally based on the Electricity Regulation Act 4 of 2006 (ERA), the National Energy Regulator Act 40 of 2004, and the Electricity Regulation Amendment Act 38 of 2024. The 2024 amendment provides for a Transmission System Operator and assigns the relevant functions to NTCSA during the transition. (South African Government)

The regulation of an NTC therefore involves much more than physical operation of power lines. It encompasses licensing, grid access, tariffs, system security, transmission planning, market operation, non-discrimination, reliability, investment and regulatory oversight.

2. Meaning and Nature of a National Transmission Company

Transmission is the conveyance of electricity through a high-voltage transmission system from generation facilities toward distribution networks and major consumers.

A national transmission company generally performs two related but legally distinguishable functions:

Transmission network ownership and management;

System operation, including balancing supply and demand and maintaining grid security.

Modern electricity reforms increasingly seek to separate these functions from electricity generation and distribution so that the transmission network can provide neutral and non-discriminatory access to competing generators and traders.

South Africa's 2024 legislation expressly provides for the establishment of a Transmission System Operator and identifies functions including transmission, system operation, market operation and central purchasing. (South African Government)

3. Statutory Framework

The Electricity Regulation Act 4 of 2006 established a national regulatory framework for electricity and made the National Energy Regulator of South Africa (NERSA) the custodian and enforcer of that framework. It regulates activities including generation, transmission, distribution, trading and electricity imports and exports through licensing and registration mechanisms. (South African Government)

The Electricity Regulation Amendment Act 38 of 2024 significantly develops this framework. It provides for:

a Transmission System Operator;

transmission-system planning;

system operation;

market operation;

competitive electricity trading;

transmission charges;

third-party access;

transmission development planning; and

regulatory approval of important transmission arrangements. (South African Government)

The amendment commenced on 1 January 2025. (South African Government)

4. Role of NERSA

The NTC does not operate outside regulatory supervision. NERSA remains central to the regulatory architecture.

Its functions include licensing and regulatory oversight of electricity activities. The courts have recognised the breadth of NERSA's statutory regulatory powers.

In Eskom Holdings SOC Ltd v Vaal River Development Association (Pty) Ltd [2022] ZACC 44, the Constitutional Court explained that the ERA requires licences for electricity generation, transmission and distribution and gives NERSA extensive regulatory authority over licence conditions, tariffs, performance standards and electricity-supply obligations. (SAFLII)

This establishes an important principle:

A national transmission company, despite being state-owned or strategically important, remains subject to the statutory electricity-regulatory framework.

5. Transmission Licensing

Transmission is a regulated activity. The legal framework requires appropriate licensing and permits regulatory authorities to attach conditions to licences.

A transmission licence may address matters such as:

network reliability;

quality of electricity services;

transmission charges;

grid access;

maintenance;

technical standards;

system security;

customer and generator relationships; and

compliance with grid codes.

The Constitutional Court in Eskom v Vaal River Development Association confirmed the broad scope of NERSA's regulatory jurisdiction under the ERA. (SAFLII)

6. Non-Discriminatory Grid Access

One of the most important principles of NTC regulation is open and non-discriminatory access.

Section 34B of the amended framework requires a transmitter to provide non-discriminatory access to the transmission power system to third parties. (South African Government)

This becomes increasingly important where private renewable-energy producers seek to connect solar and wind projects to the national grid.

The transmission company should therefore not favour:

its own generation;

particular generators;

particular customers;

particular technologies; or

affiliated market participants.

Instead, access should be governed by transparent technical and economic criteria.

7. Transmission Tariffs and Charges

Transmission networks are capital-intensive natural monopolies. It would generally be inefficient to construct competing high-voltage networks alongside one another.

Consequently, regulation is required to prevent monopoly pricing while allowing the transmission company to recover efficiently incurred costs.

The amended legislation provides that transmission-use-of-system charges and transmission charges are developed by the transmitter subject to approval by the regulator. (South African Government)

Tariff regulation therefore attempts to balance:

cost recovery;

investment incentives;

affordability;

grid expansion;

reliability;

non-discrimination; and

long-term sustainability.

8. System Operation and Grid Security

A national transmission company has a fundamental responsibility to maintain the stability of the electricity system.

Under the amended framework, the system operator must operate the integrated power system in a safe, secure, efficient and sustainable manner. It is also responsible for forecasting and dispatch scheduling and for planning the strengthening and upgrading of the national transmission system. (South African Government)

This function is particularly significant during:

electricity shortages;

sudden generation failures;

extreme weather;

renewable-energy intermittency;

transmission congestion;

cyber incidents; and

system emergencies.

9. Transmission Development Planning

Transmission regulation also involves long-term infrastructure planning.

The transmission company must consider:

projected electricity demand;

generation expansion;

renewable-energy zones;

industrial development;

grid congestion;

system-security requirements;

storage;

cross-border electricity flows; and

retirement of existing generating capacity.

The 2024 amendments specifically require development and implementation of a transmission development plan. (South African Government)

This converts transmission planning from a purely corporate decision into an important regulatory and public-policy function.

10. Market Neutrality and Competition

A major purpose of separating transmission from generation is to prevent control over the grid from being used to distort electricity competition.

South Africa's reform framework seeks to create an open market platform for competitive electricity trading. The 2024 legislation gives the future Transmission System Operator market-operation responsibilities, including establishing transparent and non-discriminatory trading arrangements subject to regulatory approval. (South African Government)

This creates a structural distinction between:

Generation → Transmission/System Operation → Distribution/Retail

The transmission operator is therefore increasingly expected to function as a neutral platform connecting market participants.

11. Important Case Laws

A. Eskom Holdings SOC Ltd v Vaal River Development Association (2022) — Constitutional Court

This is one of the most important cases for understanding electricity regulation.

The Constitutional Court examined the regulatory framework established by the ERA and emphasised NERSA's extensive statutory authority over electricity licensees.

The Court explained that electricity activities require licensing and that licence conditions can address tariffs, service quality, performance obligations and other aspects of electricity supply. (SAFLII)

Legal significance:
The case demonstrates that even a major national electricity utility operates within a statutory regulatory system rather than possessing unlimited commercial discretion.

B. Eskom Holdings SOC Ltd v Lekwa Ratepayers Association (2022)

The Supreme Court of Appeal dealt with electricity-supply obligations and the relationship between Eskom, municipalities and NERSA.

The Court recognised Eskom's position as a licensed electricity generator, transmitter and distributor and considered the statutory framework governing electricity supply and disputes. (SAFLII)

Legal significance:
The case illustrates the importance of statutory licensing, contractual electricity arrangements and NERSA's dispute-resolution role.

C. Eskom Holdings SOC Ltd v Sonae Arauco (2024)

This case concerned Eskom's system-operation obligations and the legal status of grid codes.

The Supreme Court of Appeal noted that NERSA had issued codes regulating load shedding and system operation and that these codes formed part of licence conditions. The Grid Code required the system operator to take remedial measures to protect reliable system operation, including load shedding where necessary to maintain system integrity. (SAFLII)

Legal significance:
Grid codes are not merely technical guidelines; they can constitute enforceable components of the regulatory licensing framework.

D. Sibanye Gold v Eskom Holdings SOC Ltd (2026)

In Sibanye Gold (Pty) Ltd and Others v Eskom Holdings SOC Ltd and Others [2026] ZAGPJHC 123, the Gauteng High Court considered Eskom's refusal of a wayleave application relating to transmission infrastructure and a proposed solar photovoltaic project.

The Court set aside Eskom's refusal after finding that the decision was based on an improper purpose and ordered the wayleave application to be granted. (SAFLII)

Legal significance:
The case illustrates that decisions concerning access to transmission infrastructure can be subjected to administrative-law review and must be exercised for lawful purposes.

12. Administrative Law and Accountability

Because an NTC performs a strategically important public function, its decisions may have significant consequences for:

electricity producers;

municipalities;

mining companies;

industrial consumers;

renewable-energy developers; and

ordinary electricity users.

Accordingly, decisions affecting grid access, infrastructure permissions, tariffs and system services may be challenged under administrative-law principles where the statutory requirements are not satisfied.

The Sibanye litigation demonstrates the practical importance of lawful decision-making in transmission-related infrastructure decisions. (SAFLII)

13. NTC Regulation and Renewable Energy

The regulatory importance of the NTC has increased with the expansion of renewable electricity.

Solar and wind projects are often located far from major demand centres. Consequently, large investments in transmission infrastructure are necessary.

An effective NTC regulatory framework must address:

connection queues;

grid-capacity allocation;

curtailment;

transmission congestion;

connection costs;

priority rules;

renewable-energy integration;

storage;

ancillary services; and

cross-border electricity trading.

The principle of non-discriminatory access is particularly important because transmission constraints can otherwise become a barrier to market entry.

14. Cybersecurity and Physical Security

Modern transmission networks are critical infrastructure. Regulation therefore increasingly encompasses:

cyber-risk management;

protection against physical attacks;

communication-system security;

emergency-response procedures;

data protection;

system redundancy;

incident reporting; and

business continuity.

A transmission failure can have consequences far beyond a single commercial dispute because the national grid supports hospitals, communications, water systems, transport and industry.

15. Independence of the Transmission Operator

An important institutional issue is functional independence.

The government announced that the reform framework is intended to establish an independent transmission company acting as custodian of the national grid. (South African Government)

The legal objective is to prevent the transmission network from being used to favour particular generators or market participants.

The 2024 legislation provides for a Transmission System Operator and, during the transition, assigns relevant functions to the National Transmission Company of South Africa. (South African Government)

16. Relationship Between Regulation and Energy Security

Transmission regulation is directly connected with energy security.

An NTC must ensure that the network can accommodate changing generation patterns while maintaining adequate reliability.

This requires coordination between:

Generation planning + transmission planning + demand forecasting + storage + system operation + market regulation.

The transmission company therefore becomes a central institution in the energy transition.

17. Challenges in NTC Regulation

Major legal and regulatory challenges include:

Grid congestion — limited transmission capacity can delay new projects.

Tariff disputes — users may challenge the allocation of network costs.

Market neutrality — the operator must remain neutral among competing participants.

Renewable integration — variable generation requires sophisticated system management.

Infrastructure investment — substantial capital is required for grid expansion.

Administrative accountability — transmission decisions must comply with public-law requirements.

Cybersecurity — digitalised grids create new regulatory risks.

Institutional restructuring — separating transmission from generation requires clear legal allocation of responsibilities.

Cross-border trade — interconnected electricity systems require harmonised regulatory rules.

18. Conclusion

National Transmission Company regulation is fundamentally a system of economic, technical and public-law regulation designed to ensure that the national electricity grid remains reliable, neutral, accessible and financially sustainable.

In South Africa, the Electricity Regulation Act 2006 established the basic regulatory architecture, while the Electricity Regulation Amendment Act 38 of 2024 significantly restructures transmission by providing for a Transmission System Operator, competitive electricity trading, transmission planning, non-discriminatory grid access and regulated transmission charges. (South African Government)

The cases involving Eskom, NERSA, municipalities, industrial consumers and renewable-energy developers demonstrate that transmission regulation is not merely an engineering matter. It involves licensing, administrative law, tariff regulation, public accountability, competition and energy security. Eskom v Vaal River Development Association, Eskom v Lekwa Ratepayers Association, Eskom v Sonae Arauco, and Sibanye Gold v Eskom collectively illustrate how courts supervise the legal boundaries within which major electricity-network operators must act. (SAFLII)

Thus, the modern NTC is increasingly conceived not simply as a transmission utility, but as a regulated neutral platform essential to a competitive, secure and increasingly renewable electricity market.