Sonardyne International and XOCEAN have successfully used an unmanned surface vessel (USV) to carry out a live seabed-to-shore data harvesting mission for oil and gas firm A/S Norske Shell, as part of a seabed monitoring campaign at the giant Ormen Lange field off the coast of Norway. The mission was completed without a single person having to travel offshore or from their home office, and with significantly less emissions, health and safety risk and cost than with a manned vessel.
The XOCEAN XO-450 USV was used to harvest data from an array of Sonardyne’s long-endurance Fetch pressure monitoring transponders (PMTs). Deploying the USV instead of a crewed vessel saved an estimated 5.4 tonnes of CO2 per day from entering the atmosphere, as XOCEAN’s USVs have a negligible carbon footprint, with all other emissions being offset to create a fully carbon neutral operation.
The USV travelled a total of 300 km from Kristiansund out to the Ormen Lange field and back over a period of three days. The vessel was initially ‘posted’ to Norway and then launched by local marine operations service provider, SafePath AS. All other team members, including Sonardyne’s remote operations specialists in the UK, XOCEAN’s USV pilots in Ireland, and Shell’s geophysicists in Norway and the US, remained working from their home offices.
Sonardyne’s long-life Fetch PMTs accurately collect pressure, temperature and inclination data at the seafloor at pre-programmed intervals, and this data can be used to calculate any vertical displacement of the seabed. The transponders in the Ormen Lange field array were deployed at depths of 800 to 1100 metres to support a long-term seabed monitoring campaign that will help Norske Shell to proactively inform its reservoir management strategy.
The Fetch PMTs incorporate a high-speed acoustic modem, which allows stored data to be extracted at any time, wirelessly through the water, on demand. On this mission, the XO-450 was equipped with a compatible Sonardyne acoustic transceiver attached beneath its hull.
Shaun Dunn, Sonardyne’s Global Business Manager for Exploration and Surveillance, commented: “We have always been big advocates of collecting data from our subsea instruments remotely using autonomous platforms. This technology is now coming of age and makes complete sense when thinking about the environment, the safety of offshore personnel and minimising cost. What’s more, thanks to the low hull and propulsion noise USVs can achieve, the data gathering is also faster, adding further to the efficiencies of this approach.”
James Ives, CEO of XOCEAN, stated: “Our USV platform has demonstrated itself to be a safe, reliable and ultra-low carbon solution for the collection of ocean data. We are delighted to be working with A/S Norske Shell and Sonardyne International on this ground-breaking project.”