Abstract: Systems and methods are provided for insulating and heating a subsea pipeline. A system may comprise a subsea pipeline including a lower portion embedded in a seafloor and an upper portion above the seafloor. The system may include an insulating layer. The insulating layer may include a middle portion covering the upper portion of the subsea pipeline. The insulating layer may further include an end portion covering the seafloor. The insulating layer may form a cavity adjacent to the seafloor, the subsea pipeline, and the insulating layer. The system may further include a plurality of heater cables within the cavity. The plurality of heater cables may be configured to heat a fluid within the subsea pipeline. The plurality of heater cables may be separated from the subsea pipeline only by seawater or by soil of the seafloor within the cavity.

Abstract: Systems and methods for removing buildup from a subsea pipeline are described herein. A buildup removal system comprises a conduit for transporting contents, wherein the conduit comprises a lower portion and a riser portion. In the system, a heating mechanism is configured to apply heat to a section of the lower portion and generate heated contents within the conduit, and the heated contents comprise a temperature that removes buildup from sidewalls of the riser portion.

Abstract: Systems and methods are provided for insulating and heating a subsea pipeline. A system may comprise a subsea pipeline including a lower portion embedded in a seafloor and an upper portion above the seafloor. The system may include an insulating layer. The insulating layer may include a middle portion covering the upper portion of the subsea pipeline. The insulating layer may further include an end portion covering the seafloor. The insulating layer may form a cavity adjacent to the seafloor, the subsea pipeline, and the insulating layer. The system may further include a plurality of heater cables within the cavity. The plurality of heater cables may be configured to heat a fluid within the subsea pipeline. The plurality of heater cables may be separated from the subsea pipeline only by seawater or by soil of the seafloor within the cavity.

Abstract: Systems and methods are provided for storing excess heat from subsea flowlines. The methods described herein may include generating power from a renewable energy source; heating one or more heater cables surrounding a subsea flowline with the power from the renewable energy source to a temperature at least a threshold above a temperature necessary to prevent hydrate or wax formation within the subsea flowline; storing excess heat generated by the one or more heater cables in the seafloor; and decreasing a heat loss of the subsea flowline with the excess heat generated by the one or more heater cables when the power from the renewable energy source is insufficient to heat the one or more heater cables to the temperature necessary to prevent hydrate or wax formation within the subsea flowline.