Oil and Gas Operators are moving active production and injection equipment onto the seabed with the aim of reducing CAPEX and/or topside space requirements. Moreover, they want to minimize new production floating facilities (e.g. through tie-back to existing FPSO/Floaters). Given this scenario, the overall electric power needs may become an issue because of the extra power demand due to the increasing number of electric consumers placed subsea. These electric loads may include the subsea boosting (pumps or compressors) operations, pipeline heating or the typical subsea water, chemical injection and valves actuation (in the case of all electric control systems), just to mention some of potential subsea power consumers, and may exceed the existing FPSO/Floater power production capacity. A potential solution to overcome this issue consists of the deployment of wind generators combined with topside Island power generation. Offshore wind power is indeed more and more considered for shore power supply, but also by the Oil and Gas industry with the objective of reducing the carbon footprint of their facilities. High power marine wind generators are already consolidated technologies for near coast, and today they are evolving in the short-term to floating solutions for the open sea. Saipem has developed its own floating wind turbine solution, called Hexafloat, consisting in a pendular floating foundation made of tubular elements and connected through tendons to a counterweight. This solution is particularly cost-competitive for deepwater locations (thanks to the low mooring costs) even for harsh environmental conditions (thanks to an excellent stability), and will unlock the possibility to deploy large wind power generators far from the coastline in deep water. The system composed by the Hexafloat base and the wind generator may be equipped with onboard back-up generation utilities to provide continuous power supply for subsea, despite wind intermittency, and to provide support to certain subsea field development services, making the assembly a kind of supporting device for the subsea field or for the FPSO. This is the Windstream concept that is under internal development and that will be better described in the present paper through the explanation of the results achieved within a couple of case-studies analyzed.

Chemical injection in subsea fields is a consolidated practice to solve or prevent flow assurance issues that may occur linked to hydraulic, thermal and operability requirements, especially in transient conditions. The traditional approach adopted to supply chemicals to a subsea tieback is to position the chemical injection system, including pumps and storage, on the platform/FPSO, transporting the chemicals subsea through the umbilical or the chemical lines in case of high flow rates, and performing chemical distribution subsea up to the injection points. In the development of a long subsea tieback, costs for the umbilical system tend to increase based on its length and complexity. Moreover, pressure drops and control of chemical delivery pressures and flowrates through such a long umbilical can be extremely challenging, together with the risk of umbilical line blockages and their related issues. The design resolution to enlarge the diameter of the chemical conduits in umbilicals leads to an increase in unit weights and, combined with the umbilical length, additional costs and packing and installation challenges. These factors drive the need to review the conventional chemical injection system architecture and to make the development of a long tieback sustainable from the point of view of cost and technology. To overcome these major criticalities, the chemical injection system can be placed subsea, possibly close to the injection points. Recently, Saipem has mapped the typical chemical demand for a representative size oil fields, with the main aim of defining a subsea chemical injection system architecture and its related main components. The main result of this exercise is the definition of a configurable architecture for subsea chemical storage, injection and refilling facilities to be located close to the subsea users, based on operating consideration suitable for offshore and deepwater scenarios. A "building block" approach is followed together with a certain degree of equipment standardization, where possible, allowing for a flexible system that can be adapted and tailored to the specific field. Technology development status has been also considered and specific Saipem technologies, currently under qualification or being patented, have been considered and integrated in the concept.