Case Study - Battery Energy Storage Systems

In late 2021, a Northern Territory state government tender was awarded to Hitachi Energy to supply a large-scale battery energy storage system (BESS) for State Government-owned power producer Territory Generation’s Channel Island Power Station.

Part of the larger Darwin-Katherine Electricity System Plan – which targets net zero by 2050 and 50 percent renewable energy by 2030 – the BESS contract has been described as the cornerstone for other steps to encourage low-emissions manufacturing, zero-emissions data centres, renewable hydrogen development in the region, and schemes for home and business battery storage and for solar in schools.

Technically known as inverter switchrooms, the BESS enclosures are complementary to the separate battery enclosures, and together are capable of storing and converting direct current (DC) to alternating current (AC) power, providing contingency Spinning Reserve Ancillary Services (SRAS) for the power grid.

Historically, this service was delivered by natural gas power plants for the Darwin-Katherine Electricity System network, which served approximately 150,000 customers. BESS units present a more stable, reliable energy source during power system events, and also permit greater integration of rooftop solar into the grid network.

The project had tight deadlines due to a pre-set installation date on-site

Hitachi Energy required an engineering partner to integrate their proprietary power grid technology into assembled working units for local conditions.

With the range of in-house electrical, mechanical and structural engineering capabilities at their Newcastle NSW site, Murray Engineering presented a complete solution to streamline the design, development and fabrication process from carpentry and electrical to painting, fit-out, dispatch and overall project management.

With knowledge of the challenges of the harsh environmental conditions of the Northern Territory and a diversified capability portfolio, Murray Engineering was the preferred choice.

Guided by the NT Governments carbon reduction scheme the Darwin Katherine BESS (DK BESS) project was required to achieve five crucial goals:

• Cut carbon emissions from the electricity network
• Provide greater stability, reliability, and flexibility to the network
• Allow full integration of solar energy into the grid
• Withstand environmental conditions
• Generate cost efficiencies in maintenance

Using Hitachi Energy’s virtual synchronous machine technology and other components, the DK BESS runs continuously to level out fluctuations in solar generation, negating the need for gas.

Twelve of the 35MW enclosures worth a combined total of $4,000,000 were installed to provide adequate storage capacity now and into the future.

With its humid tropical climate and high ambient temperature year-round, the NT is notoriously challenging for infrastructure design and implementation. This fact is exacerbated for any technology that generates mechanical and/or chemical heat.

The BESS was engineered to withstand the tough NT conditions through unique thermal capabilities in its construction materials, and cooling and ventilation system design.

The project achieved all five goals with resounding success. Carbon emissions of the network were significantly reduced, with the units helping to remove around 58,000T of carbon from the atmosphere by directly replacing a gas-fired generator.

The network now has greater flexibility and reliability by integrating a high-tech power bank into the system when events such as brownouts and machinery breakdowns occur.

With approximately one in six households having rooftop solar, battery storage capacity in the grid enables the capacity and feasibility for more homes and businesses in the region to utilise energy systems for their own power requirements.

The BESS units have been engineered to the highest standards in design, technology and construction materials to withstand the harshest environmental conditions, with unit longevity expected well beyond the typical comparable technologies’ 20-30 year lifespan.

The total cost of the project is offset by a AU$9.8 million per annum saving in maintenance costs of the existing system, with the project effectively paying for itself within five years.