Swiss-based electrification and automation giant ABB and oil and gas majors Equinor of Norway, Total of France and Chevron of the US have jointly taken a significant step forward on the path to the subsea factory by successfully demonstrating what is said to be the world’s first subsea power technology system of its type.

ABB hosted managers from the joint industry project (JIP) and reporters in Vaasa, Finland last week to mark the completion of a 3000-hour shallow-water test of its subsea power distribution and conversion technology system.

The successful completion of the tests is cause for celebration for the JIP partners.

“For the first time worldwide, oil and gas producers will be able to access a reliable supply of up to 100 megawatts of power, over distances up to 600 kilometers and down to 3000 meters water depth, at pressures that could shatter a brick,” says Svein Vatland, vice president at ABB and director of the subsea power JIP.

Deep ocean

Vatland says this is achievable with a single cable and equipment that requires little or no maintenance for up to 30 years, making oil and gas production feasible in far-offshore and deep ocean environments.

The $100 million research, design and development JIP was initiated in 2013.

The validation of the shallow-water test at the sheltered harbour in Vaasa means the majority of the world’s offshore hydrocarbon resources are now in reach for electrification, ABB says.

“The water temperature here is between 0 and 2 degrees Celsius, comparable with 3000 metres depth, though we are not able to simulate pressure in this shallow-water test,” one ABB engineer explains.

Vatland says that all equipment has been pressure-tested and certified. “In fact, we have tested each little component separately to ensure that all parts of the system are compatible for pressure up to 300 bars," he says.

The complete subsea power distribution and conversion system includes a step-down transformer, medium-voltage variable-speed drives and switchgear, control and low-voltage power distribution, and power electronics and control systems.

Previously, only the transmission cable and subsea step-down transformer were proven to operate underwater.

By powering pumps and compressors on the seabed, closer to the reservoir, ABB says the power distribution and conversion technology can significantly reduce power consumption.

The system can draw power from onshore and the subsea power technology can connect to any power source, enabling future integrations with renewable energy such as wind and hydropower.

Capital expenditure

Based on a specific field development case from Equinor, the new technology could offer savings in capital expenditure of more than $500 million, its backers say, assuming eight pieces of power-consuming equipment, such as pumps or compressors, are linked through a single cable over a distance of 200 kilometres from other infrastructure.

The technology removes the need for surface infrastructure, enabling all production operations to be moved to the seabed.

The technology's developers say having fewer people offshore will reduce risks and improve overall safety — a trend enabled by increasing digitalisation and autonomy in offshore operations.

More than 200 scientists and engineers from ABB, Equinor, Total and Chevron have taken part in the multi-year joint effort.

Peter Terwiesch, president of ABB’s industrial automation business, says: “Moving the entire oil and gas production facility to the seabed is no longer a dream.

"Remotely operated, increasingly autonomous subsea facilities powered by lower carbon energy are more likely to become a reality as we transition towards a new energy future.”

Oil companies like Equinor, Chevron and Total have for many years dreamed of locating production infrastructure on the seabed — the so-called subsea factory — where it is more efficient and has a far lower environmental impact.

However, earlier subsea power distribution technology limited tie-back distances to less than 150 kilometres. “This is a step closer to the subsea factory”, says Vatland.

Field Development

Major step closer to the subsea factory