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Social Innovation

SPU (Spark Prevention Unit) Technology:
Technology Innovation by Hitachi Limits the Spread of Bushfires

The threat of bushfire

The 2019–2020 bushfire season burnt over 17 million hectares of land, costing Australia over $103 billion and affecting communities across NSW, ACT, Victoria, Queensland, Western Australia, and South Australia.1 Thirty-three people and over one billion mammals, birds and reptiles were killed.2 After witnessing the horrific wildfire season overseas, we are now coming into the 2020–2021 bushfire season in Australia. With Australia expecting rising temperatures and more extreme weather events, we are anticipating longer and more dangerous bushfire seasons.

Video: SPU Technology: Technology Innovation by Hitachi Limits the Spread of Bushfires

Lightning is one of the most common ignition sources in remote areas and the cause of 16% of all bushfires in Australia.3 When the electrical network is exposed to lightning, it may cause an overvoltage, which as a result could lead to a catastrophic failure of equipment and can become a potential source of fire ignition.

At Hitachi Energy, we recognise the role technology can play in tackling climate change and supporting bushfire prevention in Australia. For this reason, Hitachi Energy designed a solution to further reduce the risk of bushfires from the electricity grid, in particular to eliminate the fire risk posed by overloaded equipment on distribution networks.

bushfire burning

How surge arresters pose bushfire risk

Surge arresters provide an important function on the electrical grid by protecting critical and expensive equipment from damaging overvoltage. When the absorbed surge (overvoltage) energy is beyond the arrester’s thermal recovery/runaway threshold, the unique design of the surge arrester means that it will sacrifice itself to protect the downstream electrical equipment.

This self-sacrifice event can be quite dramatic, with the violent expulsion of hot gasses and incandescent particles which can ignite fires.

Once a bushfire has started, it has the potential to burn large areas of land and damage properties, as well as impact the health of humans and wildlife. Michael Bacon and Dylan Perera from Hitachi Energy shared how their team wanted to find a way to disconnect the surge arresters from the network before they reached this critical point of explosion.

“We began to research ways to avoid the violent arcing posed by the failure of surge arresters and essentially prevent the risk of bushfire.”

– Dylan Perera, Sales Manager at Hitachi Energy

The Co-creation of an innovative solution to help prevent bushfires

Through technological innovation and expertise, Hitachi Energy created the Spark Prevention Unit (SPU) surge arrester. United Energy and Horizon Power have installed about 2,000 SPUs across Victoria and Western Australia.

Horizon Power Spark Prevention Unit (SPU)

The SPU effectively models the current, transient thermal loading status of surge arresters and safely disconnects overloaded surge arresters from the network prior to them being driven to short circuit failure.

If a thermal overload is detected, the SPU interrupts the current flow and disconnects the surge arrester. A visual indicator lets the operator know the surge arrestor has been safety disconnected and flags a requirement to replace the equipment.

The impact of installing a Spark Prevention Unit (SPU)

For operators of electrical distribution networks, the benefit of the Spark Prevention Unit (SPU) surge arrester is that it eliminates the risk of arcing, sparking or ejection of hot particles that have the potential to start a bushfire during a thermal runaway event of a surge arrester. In doing so, this will help to further reduce the bushfire risk profile for these organisations.

Kangaroo at the bush

Hitachi Energy continues to explore solutions to mitigate the damage of bushfires with an emphasis on digitalisation. The latest enhancements include additional capability for the SPU to provide a digital status signal enabling the network operator to receive quick access to information the surge arrestor has been disconnected.

“Protecting human lives, housing, land and wildlife. That is the social impact we at Hitachi Energy want to contribute to.”

– Dylan Perera, Sales Manager at Hitachi Energy

A public safety measure

The SPU offers round-the-clock protection in remote areas as well as urban more populated areas, where catastrophic failures pose a real risk to public safety. The SPU solution helps distribution utilities move beyond compliance and to implement real actions to support bushfire prevention and reduce bushfire risk to improve the safety of people, nature and wildlife.

“We’re hoping a solution like this can be a feature in all distributors’ bushfire readiness plans.”

– Michael Bacon, Account Manager at Hitachi Energy

Hitachi Energy invented the Spark Prevention Unit (SPU) surge arrester technology and aims to support climate adaptation and resilience through the installation of SPUs in networks located in bushfire prone areas.

Hitachi’s commitment to a net-zero society

We are committed to taking climate action and playing our role in a net-zero society. Our ambition is to contribute to a more sustainable future through green technology and digital solutions. As a Principal Partner of the COP26 UN Climate Change Conference, we support companies and people at the frontline of climate change to inspire climate action. As a company, we aim to become carbon neutral across offices and factories by fiscal 2030 and across our entire value chain by fiscal 2050.