Regulatory Framework for Design, Construction and Operation of Floating Wind Turbine Platforms
Authors: Aubault Alexia , Roddier Dominique , Banister Kevin 
Published: April 2016

The installation of an offshore platform on the Outer Continental Shelf of the United States, whether for oil extraction or to support a renewable energy device, is regulated by U.S. federal and state legislations. The WindFloat Pacific Project, a US Department of Energy (DOE)-funded project which intends to install at least three floating wind turbines (FWTs) off of the US Pacific coast, needs to follow acceptable standards of design, construction and operation to obtain its permits and move forward. However, due to the novelty of FWTs such as the WindFloat, there is no explicit guidance as to which standards apply to various aspects of the project. The simple answer would be to follow guidelines for similar platforms, such as the units engaged in offshore oil and gas exploration and production. However, after the reorganization of the Minerals Management Service (MMS) in 2010, the oversight of the use of the Outer Continental Shelf was split between Bureau of Ocean Energy Management (BOEM) for renewable offshore energy and Bureau of Safety and Environmental Enforcement (BSEE) for petroleum activities. Additionally, oil production and drilling platforms are manned structures, which also fall under the jurisdiction of the U.S. Coast Guard. WindFloats, like most offshore renewable energy structures, are unmanned, thus requiring entirely different approaches to platform access, personnel and platform safety. Additionally, for not handling hydrocarbons or other hazardours chemicals and substances, FWTs present signifcantly less risk to the environment in terms of marine pollution.

WindFloats are steel structures of semi-submersible type supporting a wind turbine and tower, and are stationary units permanently moored to the seabed through chains and anchors. They are installed in a farm setting. In a commercial scale project, wind farms may consist of 50 identical structures installed within a pre-defined zone. In contrast, oil and gas platforms often operate individually and are custom built for the location and type of operation. As such, not all standards and requirements applied to offshore oil and gas facilities would directly apply to FWTs. Since the regulations do not cover all technical aspects, an alternative suite of standards and requirements must be defined to address the specific characteristics and risk profile of these units.

To achieve that, existing national and international standards, as well as class guidelines, are reviewed and applicable sections are identified. This work is performed in cooperation with BOEM, representatives of the U.S. Coast Guard (USCG), BSEE, the classification society and proposed Certified Verification Agent for the WindFloats, American Bureau of Shipping (ABS) and representatives from the Wind and Water Program of the DOE.

This paper will identify those areas where alternative standards are needed for review by regulatory agencies, due to the specific function of the FWT. It will also present the alternate regulatory compliance process to be applied for the acceptance of these standards and the definition of the compliance scheme.