The generation of power offshore has recently seen a large amount of interest and investment. Submarine power cables are essential tools in transferring power from these offshore generation sites, to where it is consumed back on land. In addition, initiatives like the European Supergrid use submarine HV interconnectors to link electrical infrastructure on a national level. This helps to improve efficiency, and reduce total power generation and its associated costs. HV cables have been studied extensively in terrestrial soils. How their behaviour alters when buried under the seafloor is essentially unknown, despite key differences between the two respective environments. In order to make full use of these assets, accurate current ratings must be obtained.