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The first portion of the complete paper includes an extended discussion of the RED and definitions needed to appreciate its conclusions that the production and consumption of fossil fuels will be reduced gradually and replaced by renewable alternatives. This is an economically threatening situation for any country whose gross domestic product is dependent upon oil. The energy transition is a slow but steady process, so nations of the Middle East are reviewing their long-term strategies. Energy-transition and renewable-energy developments, however, may offer solutions and opportunities for these nations. This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 198165, “Alternative Fuels Development in Europe: Threat or Opportunity for the Middle East?” by Maarten Van Haute, Kuwait Petroleum Research and Technology, prepared for the 2019 SPE Kuwait Oil and Gas Conference and Show, Mishref, Kuwait, 13–16 October. The paper has not been peer reviewed.
Charles Bare, 1979 SPE President and an Honorary Member of the Society, died 25 October. Bare graduated from the University of Oklahoma in petroleum engineering and began his career at Magnolia Petroleum Co. in 1954. He joined Conoco as a research scientist in Ponca City, Oklahoma, in 1961 where he developed computer applications. He was transferred to Houston in 1969 and worked in the engineering department and then in the production department where he held various engineering and management positions with responsibilities for international production operations in Libya and Indonesia. He was the exploration and production operations manager for Russia and held managerial positions in Conoco UK for 6 years.
The industry requires the ability to test system concepts in a realistic environment on a pilot-scale size. While several units up to 10 MW are being tested onshore, existing electrolyzer technology to convert power to H2 has not yet been applied offshore. However, many suppliers are developing innovative concepts and are scaling up to larger units. It has been estimated that at least 1 MW of electrolyzer capacity can be placed on an offshore platform with existing technology.
For any offshore development, especially an ORE project, a specific site investigation is required to qualify environmental, geophysical, metocean-related, and geopolitical issues. Most ORE developments will cover a significant area of ocean or seabed and will require investigation to ensure that marine life, antiquities, unexploded ordinance, and other ocean users will not be put at risk when installation and operation activities are performed. Obtaining the required permits and approvals from all those potentially affected by an ORE development is a complex and time-consuming operation. All stakeholders connected with a development must be considered because the installation could be in position for 30 or more years. A summary of the types of wind and MHK devices is presented in Table 1 of the complete paper.
Offshore wind is a rapidly maturing sector, increasingly seen as a major contributor to electricity supply in states with coastal demand centers and good wind resources. While an almost 3-decade history exists in European experience, the US only recently is beginning to move forward with grid-scale projects on national and state levels. As floating wind is scaled up, to minimize technical risks experienced in the past, formal processes will help to identify the novel features, novel applications, and highest-risk components. Large offshore wind farms have been built by all countries with coastlines on the southern North Sea, the area with the most favorable conditions: strong, consistent winds; water depths of less than 40 m; sand or clay deeper than 70 m; and close proximity to onshore electrical distribution networks and centers of high demand. Rapid reductions have been realized in the cost of electricity, calculated over the full project lifetime, from well over 200 Euros/MWhr for the first large-scale wind farms to 50/MWhr.
Maria Angela Capello is an Honorary Member of SPE, thought leader, reservoir management expert, and a proponent of diversity and inclusion and talent development. She was the first woman to supervise seismic acquisition in the jungles of Venezuela. Her career has spanned three continents, with several significant achievements across technical and management disciplines. She is an SPE Distinguished Lecturer and chair of the Distinguished Service Award Committee. She was previously an associate editor of JPT, chair of the Business, Management and Leadership Committee, and serves as director at large of the Society of Exploration Geophysicists (SEG). Capello was recently knighted by the President of Italy with the “Cavaliere dell’Ordine della Stella d’Italia,” for “her contributions to the energy sector, that elevate the prestige of Italy abroad.”
Cong, Peiwen (State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology) | Teng, Bin (State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology) | Bai, Wei (Manchester Metropolitan University) | Ning, Dezhi (State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology)
A combined concept consisting of a torus-type oscillating water column (OWC) device and an offshore wind turbine is proposed in this study for the multi-purpose utilization of offshore renewable energy resources. The wind turbine is supported by a monopile foundation, and the OWC is coaxial with the foundation. The OWC is of torus shape, and partly submerged with its bottom open to the sea. An air duct, which houses an air turbine, is installed on the roof of the chamber. The exterior shell of the OWC is connected rigidly to the monopile by four thin rigid stiffening plates. Correspondingly, the whole chamber of the OWC is divided into four fan-shaped sub-chambers by the plates. A numerical model is then developed to simulate the wave interactions with the system as well as the air-fluid interactions within the chamber by establishing an extended boundary integral equation and using a higher order boundary element method. In addition, the optimal pneumatic damping coefficient, which is expressed in terms of radiation susceptance and radiation conductance, is determined by solving a pressure-dependent wave radiation problem. Based on the developed model, a detailed numerical analysis is conducted, and the hydrodynamic characteristics related to the combined concept are explored.
The ocean is vast and powerful, enabling marine renewable energy potentially be a significant energy supply. Due to the high-power density and longtime availability, considerable efforts and advances have been made in exploiting the marine renewable energy. A variety of wave energy converters has been invented to harvest the wave energy. In the meantime, many offshore wind energy converters have been used to harvest the available enormous wind energy resources.
Among different classes of designs, the oscillating water column (OWC) device has been widely regarded as one of the most promising options (Falcão, 2010). A typical OWC device mainly consists of two key components: a collector chamber with an underwater bottom open to the sea and a power take-off (PTO) system, mostly an air turbine, on the roof of the chamber (Heath, 2012). The incident waves excite the water column inside the chamber to oscillate, and transfer energy to the air above the water column. The pneumatic power can then be converted into electricity when the air flows through the air turbine coupled with an electric generator. Due to the nature of simplicity, the OWC device can be flexibly adapted to the shoreline, nearshore and offshore through different forms.
Liang, Zuodong (College of Architecture and Civil Engineering, Qingdao University of Technology) | Jeng, Dong-Sheng (College of Architecture and Civil Engineering, Qingdao University of Technology / School of Engineering & Built Environment, Griffith University Gold Coast Campus)
In this paper, unlike most previous investigations have been limited to the purely wave conditions or combined wave and current condition, a numerical model for random wave-induced seabed response around a pipeline in a trenched layer is established. Based on Longuet-Higgins random wave theory and finite volume method. The seabed is treated as a poro-elastic medium and characterized by Biots consolidation equations (QS model). The B-M spectrum is considered in the new model for the simulation of random waves. Numerical examples demonstrate the significant influence of irregularity of random waves on the wave-induced pore-water pressures and the resultant seabed liquefaction around the trenched pipeline, which is different from the cases under the regular waves or waves plus ocean current loading.
Trenching pipelines are an effective solution for the transportation of offshore fossil energy resources, i.e., oil and natural gas in either shallow or deep water. As the seabed level changing during the event of a storm, the liquefaction of the seafloor around pipelines subjected to the combined action of non-linear ocean state becomes increasingly important (Palmer and King, 2008; Fredsøe, 2016). For all these, the numerical analysis of trenching pipelines can highlight how the stability of its nearby seabed affected by nonlinear sea loads, and improve its hydrodynamic load prediction.
For this purpose, there are numerous studies related to the seabed response caused by waves around partially buried pipelines in trench layers available in the literature. Among these, most previous studies considered the momentary soil response near the pipeline is subjected to (1) regular wave loadings (Lin
The Spar-type FOWT, which is a kind of the stable offshore wind generator, has been widely adopted and investigated in recent years. As a permanent mooring structure, it faces the issue on mooring line fracture. In the present work, the simulations are conducted in time domain to investigate its transient response in scenarios with fractured mooring lines. Towards this end, our in-house code SFND, which is a coupled aero-hydro-elastic numerical model is adopted to perform the simulations. The methodology includes a blade-element-momentum model for aerodynamics, a nonlinear model for hydrodynamics, a nonlinear restoring model of SPAR buoy, and a fully nonlinear dynamic algorithm for intact and fractured mooring lines. The simulations are conducted under both stochastic and freak wave scenarios. The motions of platform, the tensions in the mooring lines and the power generation performance are documented in different cases. According to the results, the large drift motion is observed and the transient response is discussed.
During the recent decades, the wind energy has attracted more and more attention because of its advantages and features, such as no pollution, no carbon emission, and so on. However, with the issues on the land limitation and the noise, the installation of the onshore wind turbines nearly reaches the bottleneck. Therefore, the wind turbines are designed to be supported by the offshore foundations, in order to catch the offshore wind energy, which is less turbulence and more strength than the onshore one. Generally, the fixed foundations, including pile, gravity, jacket, etc., are widely adopted. Nevertheless, according to previous research, the costs and difficulties of the installation and maintenance increase exponentially when the water depth exceeds 50m (Leimeister et.al, 2020). To overcome this situation, the floating offshore wind turbines (FOWTs) are proposed.
The conceptual designs of the floating foundation are basically based on the experiences from the oil and gas industry (Hsu, 2017). Hereby, the different types of the floating foundations can be majorly divided into three types, which contains the Spar type, the Semi-submersible type and the Tension Leg Platform (TLP) type. Among these innovative designs, the Spar buoy shows both well hydrodynamic performance and robustness according to numerical simulations and wave basin tests (Yang et.al, 2020, Salehyar et.al, 2017, Li et.al, 2018a, Duan et.al, 2016). Even more, the first floating wind farm, Hywind Scotland, also adopted five Spar-type FOWT and successfully generate power more than two years.
He, Zechen (The State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology ) | Ning, Dezhi (The State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology ) | Gou, Ying (The State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology )
An optimization model of buoy dimension of wave energy converter is established by using differential evolution algorithm. The linear potential flow method is used in hydrodynamic calculation. Taking the vertical oscillating cylindrical buoy as the research object, the radius and draft of the buoy are optimized under each specified volume. Through the comparison of different volume optimization results, it is found that there is an optimal buoy volume for a specific wave condition. With the increase of the volume, the optimal draft tends to a fixed value, and the optimal radius tends to be an asymptote. In addition, the influence of different damping of power take-off systems on the optimization results is also studied.
Wave energy is a kind of renewable and clean energy. The development and utilization of wave energy is attracting the attention of many scholars and research institutions around the world, which may make a significant contribution to the world' power consumption. For the commercial feasibility of wave energy, it is very important to improve the production efficiency of wave energy device and reduce its construction, installation and operation costs. Obviously, the volume of the Wave Energy Converter (WEC) is a key factor affecting both the efficiency and the cost. De Andres et al. (2015) discussed that small equipment is usually more economical due to reduced material costs and deployment. Göteman et al. (2014) and Göteman (2017) showed that the total power production can be improved if the wave energy array consists of devices of different dimensions that are similar to the WECs that have been developed at Uppsala University since 2006 (Leijon et al.,2009). Most previous optimal studies focus on the buoy dimensions instead of the buoy volume. For example, Giassi and Göteman (2017) optimized the parameters of the single wave energy converter by parameter sweep optimization of the variables and genetic algorithm, in which the radius, draft and damping of the Power Take Off (PTO) systems are optimized simultaneously in discrete parameter space. Because there are many combinations of radius and draft under a certain volume even for a truncated cylinder buoy, it' difficult to get the relationship between the volume and the efficiency directly. That means the designer couldn't balance the cost and the efficiency with the optimal dimensions.