VESSEL REVIEW | Resilience – US Department of Energy places hybrid research vessel into service

The US Department of Energy (DOE) recently took delivery of a new hybrid electric research vessel to be operated by its affiliate Pacific Northwest National Laboratory (PNNL) out of Sequim, Washington.

Built at the Seattle facilities of Snow and Company, the all-aluminium Resilience was designed to carry two crewmembers and up to six scientists. It features a dry laboratory, a flying bridge with observation stations, powerful lifting capacity with an A-frame and a knuckle boom crane, a spacious 322-square-foot (30-square-metre) deck for deploying and recovering large instrument packages, and support for a variety of sensors.

The newbuild, which is the first hybrid research vessel to be acquired by the DOE, will be operated primarily in Sequim Bay off northwestern Washington State. PNNL said the vessel is also the first of its size class to be partially electrified and is big enough to fit a 113kWh battery, but still small and manoeuvrable enough for research in Sequim Bay and other areas.

Extended-duration sailings and monitoring made possible through low-emission propulsion

The vessel has a length of 50 feet (15 metres), a beam of 16 feet (4.9 metres), a draught of only 3.5 feet (1.1 metres), and a gross tonnage of 38. Fuel and fresh water capacities are 840 gallons (3,180 litres) and 80 gallons (300 litres), respectively.

The hybrid propulsion system includes a Spear Power Systems Trident lithium-ion battery, two Volvo Penta D8 500hp (370kW) diesel engines, two Danfoss EM-PMI375-T200-2600 generators, two propellers, and two Twin Disc MGX-5075 SC gearboxes.

The vessel can sail in fully electric mode for up to four hours at six knots, while the diesel engines will deliver a maximum speed of 28 knots and a range of 400 nautical miles at a cruising speed of 21 knots. The battery can be charged at a shore station at PNNL-Sequim.

PNNL said that, with Resilience, researchers not only get a larger vessel but also a quieter one. While the vessel uses its batteries, it generates significantly low noise levels so as not to disturb wildlife as well as provide a better environment for taking sensitive acoustic measurements. The vessel’s emissions of CO2 and other greenhouse gases will also be greatly reduced.

Equipment fitout ideal for a range of research activities

The vessel’s size will not only allow researchers to travel further offshore, but it will also accommodate large research equipment like remotely operated vehicles (ROVs), ocean observing systems, and demonstration-scale marine energy devices.

The onboard equipment also includes a davit, a dedicated transducer mount, two dive platforms, and a scuba compressor, while the electronics suite includes a radar and other gear from Garmin, a GPS, and a thermal camera. The accommodation spaces include convertible sleeping arrangements for multi-day assignments.

Designed in compliance with US Coast Guard Subchapter T requirements, Resilience will be deployed on missions dedicated to studying the environmental impacts of marine energy, ocean-based carbon dioxide removal, and coastal ecosystem sciences. The vessel was funded by the DOE’s Water Power Technologies Office.