BOLT Lifesaver enables offshore remote operations with wave energy

All offshore operations rely on instrumentation and sensor systems for measurement and monitoring, as well as remotely operated robotic vehicles (ROVs) for inspection, repair and maintenance.

In the majority of cases, power and communication infrastructure is not available on site. These capabilities are therefore provided either by a surface vessel at very high cost or by batteries offering limited capacity and no real-time communication. While the offshore industry seeks to reduce the presence of people and vessels offshore by steering towards remote monitoring and operation from shore, the lack of technologies that offer reliable, cost-efficient power and communication represents a real constraint.

To accommodate this gap in technology, the Fred. Olsen company BOLT Sea Power has developed the BOLT Lifesaver, where three power take-off winches (PTO) are mounted on a 16-m diameter lifering-shaped floating structure, with the winch lines anchored to the seabed. Each winch has a generator coupled to it through a gearbox, and together the PTOs generates energy surplus by dampening the motion of the floater, up to 10kW each.

The BOLT Lifesaver weighs 60 metric tons, has 1000kWh of onboard energy storage and hosts equipment for 4G, pier-to-pier and satellite communication to shore. It operates autonomously, providing up to 30kW of power and a communication link to client systems on board or on the seabed. Installed and moored along with the offshore systems it powers, it can stay on site for years, enabling long-duration remote operation of offshore systems, while eliminating the need for surface vessels.

Fred. Olsen has more than 10 years of accumulated operation of the BOLT Lifesaver PTOs, primarily for the US Navy, demonstrating uptime and power production continuity unmatched by any other marine renewable energy technology.

The company is also working to configure a smaller product with one PTO fitted to a 5-m diameter hull and a total weight of 8 metric tons. It will provide communication and up to 10kW of power.

By providing in-situ recharge of batteries and a direct communication link to shore, BOLT Sea Power technology greatly reduces the cost of installing and operating arrays of subsea sensor systems for monitoring and measurement and deploying ROV and AUVs with docking stations.

The technology eliminates the need for offshore vessels, thereby cutting greenhouse gas emissions.

The market for BOLT Sea Power products is growing rapidly, as the subsea oil and gas and offshore wind industries are gearing up for remote and digital operation during construction, operation and decommissioning activities. Given the costly day rate for Inspection, Maintenance and Repair (IMR) vessels, the products are attractive simply in terms of reducing vessel days alone.