Wind energy is one of the key renewable energy sources that will make a significant contribution towards the goals of clean energy around the world. The offshore wind energy industry is in a period of rapid growth, which results in a massive demand on the current supply chain. The large scale development demands specific installation and maintenance vessels. Various wind turbine installation vessels are being designed or constructed with a combination of new and existing technologies. There are specific challenges and design considerations related to this kind of vessels. Understanding the critical design parameters and considerations for various design concepts of WTI units are important for proper selection of design and technical standards in order to ensure a safe and robust design. The industry needs new design standards developed with synergy from well established offshore/maritime practices to provide guidance for this new vessel type to meet the high energy demand and to ensure high safety standards in the offshore wind energy sector. The paper first presents examples of various types of Wind Turbine Installation vessels that currently are being developed and then describe how DNV rules and standards address the specific challenges and critical elements for these various types of WTI units to ensure a safe and robust design. The paper then goes on to describes some of the key parameters and methodologies by which selection of these various design concepts can be carried out for a particular project/application.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractFloating Production, Storage and Offloading (FPSO) facilities have developed over the last 40 years to become an increasingly popular solution worldwide for offshore field development. To date no FPSO has been deployed within the US Gulf of Mexico (GOM) where the dominant production facilities have been fixed structures and floating production system based on Spar, TLP, and Semi-submersible platforms. Higher oil prices and significant ultra-deepwater prospects extending farther beyond established pipeline infrastructure, make FPSOs an increasingly viable option. Operators, Contractors and new entrepreneurs worldwide want to capture that market and are committing to the FPSO solution by placing orders for speculative builds. Many of these build contracts are signed without a specific field destination or production contract in hand and are contracted with a "generic" FPSO specification. The design specification of a generic FPSO presents many challenges. Selecting a workable environmental design envelope and the type of regulatory environment the vessel should satisfy are some of the early decisions that will determine the success of the investment. This paper discusses the challenges of developing a speculative build in view of regulatory requirements worldwide and in the US GOM.