If you live anywhere in South East Queensland (SEQ) — from the Gold Coast to Gympie, or out west toward Toowoomba — Energex is your local network operator.

Energex manages a highly urbanised and rapidly growing network. Its service area includes Queensland’s largest population centres: Brisbane, the Gold Coast, the Sunshine Coast, Ipswich, and surrounding regions. This area has one of the highest concentrations of rooftop solar in the world, which has brought both opportunities and challenges for network planning and stability.

The Scope of the Energex Network

Energex’s network stretches across more than 25,000 square kilometres and supplies electricity to around 1.5 million homes and businesses. It operates over 60,000 kilometres of powerlines and maintains hundreds of substations that distribute electricity safely at different voltage levels.

Unlike its regional counterpart Ergon, Energex’s infrastructure is a mix of overhead and underground systems. Urban areas — especially in new housing estates — are increasingly served by underground cables, which are more resilient during storms and improve streetscape aesthetics. Older suburbs, however, still rely on traditional overhead lines.

Focus on Smart and Sustainable Infrastructure

In recent years, Energex has been leading the charge in modernising Queensland’s electricity network. It’s playing a key role in supporting distributed energy resources (DERs) like rooftop solar, battery storage, and electric vehicles.

To manage the growing two-way flow of electricity — where customers are not just consumers but also generators — Energex is investing in smart grid technologies. These systems allow real-time monitoring and control, helping balance voltage and load across the network as renewable generation fluctuates throughout the day.

Energex also supports dynamic export limits for solar systems, replacing fixed export caps. This allows households to send more solar energy back to the grid when there’s available capacity and automatically reduce exports when the network is constrained. It’s a win-win — customers maximise their solar investment, and the grid stays stable.

Reliability and Resilience

Being in a storm-prone region, Energex faces frequent weather challenges — from summer thunderstorms to tropical cyclones that occasionally track south. To improve resilience, Energex invests heavily in vegetation management, pole replacement, and network hardening programs.

When outages do occur, Energex’s crews are known for their rapid emergency response, often restoring power within hours thanks to advanced monitoring and control systems that quickly isolate faults and reroute supply.

Ergon Energy – Powering Regional and Remote Queensland

Now, let’s head beyond the southeast corner and into the rest of Queensland — a massive expanse that stretches from the Cape York Peninsula in the north, through the Outback, and all the way down to the New South Wales border. This vast area is the domain of Ergon Energy.

Ergon operates one of the largest electricity distribution networks in the world by geographic area — covering over one million square kilometres. Its challenge is not dense populations or high demand, but distance, isolation, and harsh environmental conditions.

The Scale of the Challenge

Unlike Energex, Ergon’s customer base is spread thinly across enormous distances. The network includes thousands of kilometres of Single Wire Earth Return (SWER) lines, which are ideal for delivering power cost-effectively to remote properties.

Ergon’s customers include farms, mining operations, small towns, and Indigenous communities — many located hundreds of kilometres from the nearest major substation. Keeping these areas reliably powered requires significant logistical effort and innovation.

The company services about 800,000 customers, but its network length exceeds 150,000 kilometres. That means many feeders run long distances to serve only a handful of customers — a major cost and reliability challenge.

Innovation and Remote Solutions

Because of these challenges, Ergon has become a pioneer in remote energy solutions. It operates dozens of isolated power systems that are not connected to the main grid at all. These systems — often powered by diesel, solar, or hybrid renewable setups — supply electricity to remote communities such as Burketown, Doomadgee, and Thursday Island.

Ergon has also been actively investing in microgrids and standalone power systems (SAPS). These allow remote customers to generate and store their own electricity, reducing reliance on long distribution lines that are expensive to maintain and prone to storm or wildlife damage.

In collaboration with the Queensland Government and the Australian Renewable Energy Agency (ARENA), Ergon is trialling new hybrid systems that combine solar panels, batteries, and small backup generators to create more sustainable and resilient local power supplies.

Reliability and Customer Service

Despite the tough operating environment, Ergon continues to meet reliability targets set by regulators. Its field crews regularly travel vast distances — sometimes by helicopter or 4WD — to maintain lines and restore power after storms or cyclones.

To improve communication with customers, Ergon has enhanced its outage notification system and invested in digital tools that allow customers to track planned maintenance and fault restoration times in real-time.

Energy Queensland – The Parent Company

While Energex and Ergon Energy operate in different regions, both are owned by the State of Queensland through a holding company called Energy Queensland Limited.

Formed in 2016, Energy Queensland brought the two DNSPs under a single corporate structure to streamline operations, reduce duplication, and improve efficiency. The merger also aimed to foster collaboration and consistency in how Queensland manages its electricity distribution.

Energy Queensland’s responsibilities include:

• – Strategic planning and investment for both networks.
• – Coordinating shared services such as procurement, IT, and engineering support.
• – Driving innovation across the state’s grid, including digital meters, smart networks, and community batteries.
• – Supporting Queensland’s renewable energy transition and decarbonisation targets.

Although Energex and Ergon remain distinct operationally — with their own branding and service areas — they share many policies, systems, and innovation initiatives through Energy Queensland.

Regulation and Oversight

Because electricity distribution is a natural monopoly — you can’t have multiple companies running duplicate sets of powerlines — both Energex and Ergon are regulated entities. Their performance, reliability, and pricing are closely overseen to ensure customers get fair and efficient service.

The Role of the Australian Energy Regulator (AER)

The Australian Energy Regulator (AER) is responsible for setting the amount of revenue each DNSP can recover from customers. It does this through five-year regulatory determinations, where Energex and Ergon must submit detailed proposals outlining their expected costs, capital investments, and service targets.

The AER examines these proposals to ensure spending is efficient and that customers aren’t paying more than necessary. It also monitors reliability performance and applies incentive schemes — rewarding DNSPs for improvements and penalising them if they fall short.

Reliability Standards

Both DNSPs must comply with Queensland-specific reliability and safety standards. These standards are measured through metrics like:

• – SAIDI (System Average Interruption Duration Index): the average total outage time per customer.
• – SAIFI (System Average Interruption Frequency Index): the average number of outages per customer per year.

Urban areas, like those served by Energex, are expected to achieve higher reliability because of their dense networks and redundancy. Regional and remote areas, managed by Ergon, have looser targets due to the physical limitations of vast rural lines.

Supporting the Renewable Transition

Queensland has one of the highest rates of rooftop solar adoption in the world. This has been a game changer for both Energex and Ergon.

Managing Solar Exports

High solar generation during the middle of the day can cause voltage rises and reverse power flows that the network wasn’t originally designed for. To manage this, both DNSPs have implemented export limits for solar systems — typically 5 kW per phase for single-phase homes.

However, with the rollout of dynamic export limits, many households will soon be able to export more power when the grid can handle it. This technology relies on smart meters and communication systems that automatically adjust export levels throughout the day.

Community Batteries and Demand Management

Energex and Ergon are also investing in community battery programs, which allow entire neighbourhoods to share a large battery that stores excess solar energy and releases it later when demand peaks.

They’re also running demand response programs, offering incentives to customers who allow their appliances — such as air conditioners or EV chargers — to be temporarily adjusted during peak demand periods. These measures help defer expensive network upgrades and reduce costs for everyone.

Future Challenges and Opportunities

As Queensland moves toward its renewable energy and decarbonisation goals, Energex and Ergon will play a central role in enabling the future grid.

Key challenges and focus areas include:

• – Integrating more distributed generation like rooftop solar, batteries, and electric vehicles.
• – Upgrading ageing infrastructure in rural areas to improve reliability and safety.
• – Expanding the use of digital technologies, smart meters, and automation for faster fault detection and response.
• – Supporting electrification of transport and industry while managing peak demand growth.
• – Reducing operational emissions and contributing to Queensland’s renewable energy targets (50% renewable by 2030).

The good news is that both Energex and Ergon are already adapting. They’re working closely with government agencies, regulators, and technology partners to ensure the network remains flexible, resilient, and ready for the future.