Offshore Energy Generation Research Articles

An Evolving Blue Economy: Exploring the Future for Marine Renewable Energy

Abstract Offshore energy generation is one of the fastest-growing U.S. marine sectors, ranging from expanding deployment of offshore wind to rapid development and testing of technologies for energy conversion from waves, tides, ocean currents, and gradients in temperature, salinity, and pressure. Generating energy from the offshore environment creates expanded opportunities to improve upon the collection of ocean and coastal-derived data and information that will support economic and maritime growth, the management of resources, and solutions to address societal and climate issues. Despite its many promises and challenges, barriers remain for widespread implementation of offshore energy generation technologies that address the nation's energy needs and climate change. A town hall was convened to present a vision of the changing ocean-scape through the lens of marine renewable technologies and to explore innovative solutions that these technologies might offer to support the New Blue Economy.

Alternatives for Transport, Storage in Port and Bunkering Systems for Offshore Energy to Green Hydrogen

Offshore electricity production, mainly by wind turbines, and, eventually, floating PV, is expected to increase renewable energy generation and their dispatchability. In this sense, a significant part of this offshore electricity would be directly used for hydrogen generation. The integration of offshore energy production into the hydrogen economy is of paramount importance for both the techno-economic viability of offshore energy generation and the hydrogen economy. An analysis of this integration is presented. The analysis includes a discussion about the current state of the art of hydrogen pipelines and subsea cables, as well as the storage and bunkering system that is needed on shore to deliver hydrogen and derivatives. This analysis extends the scope of most of the previous works that consider port-to-port transport, while we report offshore to port. Such storage and bunkering will allow access to local and continental energy networks, as well as to integrate offshore facilities for the delivery of decarbonized fuel for the maritime sector. The results of such state of the art suggest that the main options for the transport of offshore energy for the production of hydrogen and hydrogenated vectors are through direct electricity transport by subsea cables to produce hydrogen onshore, or hydrogen transport by subsea pipeline. A parametric analysis of both alternatives, focused on cost estimates of each infrastructure (cable/pipeline) and shipping has been carried out versus the total amount of energy to transport and distance to shore. For low capacity (100 GWh/y), an electric subsea cable is the best option. For high-capacity renewable offshore plants (TWh/y), pipelines start to be competitive for distances above approx. 750 km. Cost is highly dependent on the distance to land, ranging from 35 to 200 USD/MWh.

Breaking wind: A comparison between U.S. and European approaches in offshore wind energy leadership in the North Atlantic region

The United States has only recently begun investing in commercial-scale offshore wind energy (OWE). Although the United States is slow to progress, it is uniquely positioned to build on the existing knowledge that coastal European countries have applied for their own energy transitions. In this study, we analyze how federal and regional plans for expanding the OWE sector in the United States brought to the surface decade-long tensions related to multi-scale governance mismatches, jurisdictional conflicts, and unclear pathways for implementing national industrial policies. Drawing upon the European experience with OWE, we employ a dynamic multi-level perspective framework enriched by socio-ecological elements to examine the United States energy transition through its most promising technology. From our framework we identify six categories of OWE developments characterized by both unique and shared elements between the United States and European coastal countries. These elements are: (1) role of local communities, (2) governance structures, (3) multi-scale government interactions, (4) regional socioeconomic structures, (5) socio-ecological impacts, and (6) relationships with existing industries. Drawing upon our analysis, we identify and conceptually map four research areas in need of further development for the United States and the research community— (1) knowledge, (2) potential, (3) adaptation, and (4) learning. These insights provide critical information to ensure that the United States expansion into offshore energy generation is characterized by elements of justice, equity, and inclusive regional economic development.

The Interplay Between EU Law and Regional Sea Conventions: Shaping Environmental Protection in Relation to Offshore Energy Production Across Europe?

Despite the EU’s ambitious goals regarding the expansion of marine renewables as a promising climate mitigation and energy security measure, the majority of hydrocarbon exploitation continues occurring offshore with more than 500 oil and gas installations operating in European seas. Given the grave environmental risks these activities pose, the EU has developed secondary rules with implications for the regulation of offshore energy generation. These normative developments have added an extra layer of regional, supra-national regulation of ocean energy production across European seas, which necessarily interacts with the simultaneously applicable rules under regional sea agreements. The article examines the implications of the normative interplay between EU law and regional sea agreements in terms of shaping the environmental regulation of offshore energy production across Europe. In that respect, it explores whether EU law instruments and the EU’s sophisticated institutional framework can enhance the rules and standards under the regional sea agreements, in terms both of adding normative content to them and supporting their enforcement. In light of the mutual cross-fertilization between the two applicable regimes, the article equally looks into the normative impact of regional sea conventions on the EU legal framework and its implementation in the context of offshore energy production. Offshore energy, regional sea agreements, normative interactions, marine environmental protection

Integration of wind and tidal turbines using spar buoy floating foundations

<abstract> <p>Floating platforms are complex structures used in deep water and high wind speeds. However, a methodology should be defined to have a stable offshore structure and not fail dynamically in severe environmental conditions. This paper aims to provide a method for estimating failure load or ultimate load on the anchors of floating systems in integrating wind and tidal turbines in New Zealand. Using either wind or tidal turbines in areas with harsh water currents is not cost-effective. Also, tidal energy, as a predictable source of energy, can be an alternative for wind energy when cut-in speed is not enough to generate wind power. The most expensive component after the turbine is the foundation. Using the same foundation for wind and tidal turbines may reduce the cost of electricity. Different environment scenarios as load cases have been set up to test the proposed system's performance, capacity and efficiency. Available tidal records from the national institute of Water and Atmospheric Research (NIWA) have been used to find the region suitable for offshore energy generation and to conduct simulation model runs. Based on the scenarios, Terawhiti in Cook Strait with 110 m water height was found as the optimized site. It can be seen that the proposed floating hybrid system is stable in the presence of severe environmental conditions of wind and wave loadings in Cook Strait and gives a procedure for sizing suction caisson anchors.</p> </abstract>

Threading a moving needle: The spatial dimensions characterizing US offshore wind policy drivers

The Atlantic Coast of the United States represents one of the most promising development environments for offshore wind installation in the world due to the convergence of several geographic factors. These include, but are not limited to, population size and density, electricity prices, ocean depth, wind speed, and the dynamics of the region's current energy infrastructures. However, these have not been sufficient to kickstart a mass movement to offshore energy generation despite two decades of affirmative discussions and some entrepreneurial starts. Planned projects now total over 6 GW. Presently, market variables and institutional controls have become more hospitable for development though undertested except in small pilot projects. Socio-cultural concerns including interaction with the fishers, coastal tourism and real estate, Native American Tribes, and environmental and aesthetic factors have been studied, but applicable information remains limited to reliance on comparisons with European offshore wind research, hypothetical analyses, and attention to small pilot projects. This gap as well as a fundamentally differentiated patchwork of state and local stages means that the current research direction will need to be extended through the development of the first utility-scale projects with attention to new case studies as well as new perspectives, framings, and questions. This report outlines important physical and social policy factors of offshore wind development and then explores several case studies.

A Markovian reliability approach for offshore wind energy system analysis in harsh environments

AbstractFor an effective monitoring strategy of offshore energy systems in harsh environments, it is vital the system reliability dynamics be fully understood. This article presents the application of a Markovian process for dynamic reliability prediction of an offshore energy system. In the proposed approach, a three‐state Markovian process is developed for the analysis of the subsystem states, which dynamically determines the overall system reliability performance, overcoming the static limitation of fault tree analysis. The multistate subsystems are discretized into normal, degraded, and failed states to demonstrate the performance dynamics of the system for condition monitoring. The proposed approach is tested on a case study and the most critical influencing elements are identified. The application of the methodology efficiently identifies the system vulnerability path so as to assist in system integrity management and to provide a guide to early remedial action against total failure and downtime in offshore energy generation.

Process and Material Parameter Optimisation of Rotomoulded Polymer Foams

Polymer foams are essential for the manufacture of low cost, lightweight, buoyant structures typical of offshore energy generation devices. Careful balancing of material and processing conditions is essential to achieving a mechanically optimal cellular structure. To date, a convenient method for optimising rotationally moulded polymer foams has not been demonstrated. An offline experimental method was developed, and a preliminary study conducted, analysing the influence of processing and material parameters, such as polymer particle size or chemical blowing agent (CBA) concentration, on polymer cellular structures. The density of each sample was analysed, and image analysis software used to compare the amount of cell deterioration in each specimen cross-section. The method was found to be capable of indicating appropriate levels of each variable, offering a quicker route to foam optimality based on minimising density and preventing cell deterioration.