A full-scale remote subsea power hub, driven by ocean currents, is going into the water for testing next month at the Underwater Centre at Fort William in Scotland.

The system has been developed by East Coast Oil and Gas (EC-OG), and the company’s Managing Director Richard Knox told a National Subsea Research Initiative Technology Showcase event in Aberdeen that it will be tested as part of an 18-month, £4 million (US$ 6.1 million) programme.

The tests will aim to demonstrate that it is feasible to provide information from the seabed back effectively via a satellite link to any location, without the need for an umbilical.

Knox said, “We believe things are moving toward the autonomous subsea well. Keeping a subsea well operational only needs a maximum of 100 watts to keep the subsea control module up and running and keep the oil and gas flowing, effectively keeping the lights on for us.”

He said there are almost 400 subsea wells in the U.K. North Sea, which have suffered from a temporary shut-in because of failures, which can be down to the umbilical.

Some of the key things that can affect an umbilical are water ingress, damaged seals and failures of electrical connectors. All these can lead to failure in electrical supply.

Knox said, “We have reached a point in 2015 where the average tieback distance is 20 km and some are as far back as 100 km from the host facility. The cost of getting electrical service to the well is proportional to the tieback distance. Not only are we in a situation where a large number of assets are reaching the end of their design life, they are getting to the point where failures occur much more regularly.

“If there is a failure, wouldn’t it be nice to have a simple solution, something we could just plug straight into the control module to get us back up and running and get oil and gas flowing again.”

The subsea power hub being developed by EC-OG aims to provide a predictable source of power and an energy storage solution all in a small footprint.

Ocean currents can be predicted 100 years in advance and as long as the planet keeps on turning the ocean currents are going to be there, Knox said.

“It is important from a cost perspective that we don’t overengineer the system. By knowing what is going to happen in such a long period of time reduces the engineering challenge,” he added.

The 500-watt EC-OG hub has been kept small, 2 m across, with the turbines in Delta configuration.

“We can package the turbines in a system, which is overtrawlable, easy to install and most importantly of all there is a high level of redundancy, which means we can be extremely reliable.

By keeping the unit within a small space we can create double the energy capacity. At 0.4 m per second, we can start generating useful electrical power and that is key.”

He said that because the turbines can cut in at such a low speed and generate power, the device can be installed in the same location as the infrastructure it is looking to service.

“It’s not only in the U.K. that this is the case. There are suitable ocean currents in the Gulf of Mexico, Indonesia, Australia [and] West Africa. These conditions exist globally.”

EC-OG is the only company in Aberdeen that has been awarded support by Scottish Enterprise’s top-tier High Growth Start Up Unit, whose task is to identify companies with a high potential of developing new technology that can be commercialised and used for the benefit of the Scottish economy.

Offshore