In the late summer and early autumn of 2022, Vattenfall successfully conducted large scale seabed surveys with uncrewed surface vessels. The surveys were conducted at several of Vattenfall’s offshore wind farms in Denmark, Sweden and the UK. The results were very positive, both from a climate and a safety aspect. This opens up for a broader use of this new technology.The uncrewed vessel is significantly smaller (4.5m total length) than crewed vessels, and typically also more modern which explains the big fuel saving. Uncrewed vessels are sailing drones controlled by an operator onshore. Uncrewed survey vessels reduce fuel consumption considerably, compared to conventional crewed vessels, in some of the cases up to 90%, eliminating crew from an offshore environment exposes them to fewer health & safety risks. In the summer and autumn of 2022, uncrewed vessels were used for seabed surveys across Vattenfall’s Horns Rev 1, Horns Rev 3 and Krieger’s Flak in Denmark as well as Lillgrund in Sweden and Thanet in the UK.The service was provided by ocean data acquisition company XOCEAN, who has used uncrewed survey services since 2019.As a part of operating an offshore wind farm it is necessary to periodically survey the seabed around turbine foundations and substation jacket legs to monitor changes in cable burial depth and scour development. This knowledge is also important for repair and maintenance activities involving jack-up vessels, where legs require a stable seabed to ensure safe elevation out of the water. Traditionally, seabed surveys are carried out using crewed vessels, which emit substantial amounts of carbon from the consumption of fuel.