Hydrodynamic Forces on Near-Bed Small Diameter Cables and Pipelines in Currents, Waves and Combined Flow

2019 ◽  
Author(s):  
Terry Griffiths ◽  
Yunfei Teng ◽  
Liang Cheng ◽  
Hongwei An ◽  
Scott Draper ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Oil And Gas ◽  
Experimental Testing ◽  
Small Diameter ◽  
Preliminary Test ◽  
High Energy ◽  
Operational Reliability ◽  
Hydrodynamic Forces ◽  
Design Data ◽  
Energy Projects

Abstract The on-bottom stability design of subsea pipelines and cables is important to ensure safety and reliability but can be challenging to achieve, particularly for renewable energy projects which are preferentially located in high energy metocean environments. Often these conditions lead to the seabed being stripped of all loose sediment, leaving the cables to rest on exposed bedrock where roughness features can be similar in size to the cables. As offshore renewable energy projects progress from concept demonstration to commercial-scale developments, new approaches are needed to capture the relevant physics for small diameter cables on rocky seabeds to reduce the costs and risks of export power transmission and increase operational reliability. These same considerations also apply to the cables and small diameter pipes — such as umbilicals — required by oil and gas projects located on rocky seabeds. Recent experimental testing using the University of Western Australia’s unique Large O-tube has enabled the experimental measurement of hydrodynamic forces on small diameter cables and pipes in proximity to smooth and rough beds. The tested conditions extend well beyond the existing published parameter range including much higher KC conditions together with seabed roughness which is comparable in size to the diameter. The results provide design data of great relevance to the ongoing development of marine renewable and conventional oil and gas projects, especially on rocky seabeds. This paper presents a summary of the existing knowledge on the subject as a preface to preliminary test results and gives tentative conclusions on the likely outcomes from this work.

Subsea Cable Stability on Rocky Seabeds: Comparison of Field Observations Against Conventional and Novel Design Methods

2018 ◽  
Author(s):  
Terry Griffiths ◽  
Scott Draper ◽  
Liang Cheng ◽  
Feifei Tong ◽  
Antonino Fogliani ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Power Transmission ◽  
Small Diameter ◽  
Oil And Gas Industry ◽  
Operational Reliability ◽  
Design Methods ◽  
Gas Industry ◽  
Integrity Management ◽  
Tidal Stream ◽  
Almost All

As offshore renewable energy projects progress from concept demonstration to commercial-scale developments there is a need for improved approaches beyond conventional cable engineering design methods that have evolved from larger diameter pipelines for the oil and gas industry. New approaches are needed to capture the relevant physics for small diameter cables on rocky seabeds to reduce the costs and risks of power transmission and increase operational reliability. This paper reports on subsea cables that MeyGen installed for Phase 1a of the Pentland Firth Inner Sound tidal stream energy project. These cables are located on rocky seabeds in an area where severe metocean conditions occur. ROV field observation of these cables shows them to be stable on the seabed with little or no movement occurring over almost all of the cable routes, despite conventional engineering methods predicting significant dynamic movement. We cite recent research undertaken by the University of Western Australia (UWA) to more accurately assess the hydrodynamic forces and geotechnical interaction of cables on rocky seabeds. We quantify the conformity between the cables and the undulating rocky seabed, and the distributions of cable-seabed contact and spanning via simulations of the centimetric-scale seabed bathymetry. This analysis leads to calculated profiles of lift, drag and seabed friction along the cable, which show that all of these load and reaction components are modelled in an over-conservative way by conventional pipeline engineering techniques. Overall, our analysis highlights that current cable stability design can be unnecessarily conservative on rocky seabeds. Our work foreshadows a new design approach that offers more efficient cable design to reduce project capex and enhance through-life integrity management.

Maghreb countries will bolster renewable energy sector

2018 ◽  
Keyword(s):  
Renewable Energy ◽  
North Africa ◽  
Energy Security ◽  
Oil And Gas ◽  
Solar Power ◽  
Sub Saharan Africa ◽  
Domestic Consumption ◽  
Content Type ◽  
Energy Projects ◽  
Sub Saharan

Subject Renewable energy projects in North Africa. Significance Tunisia prequalified 16 groups in November to bid for contracts to build and operate a total of 500 megawatts of solar power. The Tunisian scheme will add to a rapidly growing set of solar power projects across North Africa. Morocco has led the way, but Egypt is poised to become the largest solar power producer in the region. Algeria has ambitious plans but has been slow to put them into practice. Impacts In Algeria and Egypt, solar power will slow domestic consumption of oil and gas and maximise exports. In Morocco, which relies heavily on imported fuel, solar power will enhance energy security. North Africa may contribute to lowering CO2 emissions by becoming a major exporter of renewable energy to Europe and Sub-Saharan Africa.

scholarly journals Analysis of Energy Projects Financial Efficiency and Renewable Energy Generation in Russia

2021 ◽  
Vol 25 (5) ◽  
pp. 79-91
Author(s):  
J. An ◽  
A. Yu. Mikhaylov
Keyword(s):  
Renewable Energy ◽  
Energy Consumption ◽  
Oil And Gas ◽  
Renewable Energy Sources ◽  
Power Industry ◽  
Energy Sources ◽  
Financial Efficiency ◽  
Global Trends ◽  
Russian Economy ◽  
Energy Projects

The authors study the development of the oil and gas industry and assess the financial efficiency of the use of renewable energy sources, which determine the relevance of the research topic. The purpose of this work is to study the effectiveness of the development of the Russian energy sector and its contribution to the world economy. The main question to which this article should give an answer is that how the Russian power industry will develop in corresponding to the global trends in energy consumption. This paper uses a method for finding the parameters of the efficiency of renewable energy sources using exponential smoothing. The paper uses data from the analytical report of British Petroleum and the Bloomberg system for the period from January 2012 to December 2019. The result of the study shows an improvement in the accuracy of the predicted values, while previous models had higher standard error estimates. The novelty of the study is to achieve accurate results of the forecast of fossil-fuel consumption for 3 years ahead (the forecast accuracy is 80.5). The article concludes that while Russian oil and gas projects are very important for the Russian economy until now, renewable energy projects are more beneficial. In addition, Russia does not seem to support the global trend towards a renewable and sustainable economy. Although oil and gas prices remain acceptable, unforeseen changes in the behavior of real buyers can hinder the efficiency of the Russian economy and lead to a disruption of Russia’s economic growth if Russia does not decisively steer towards renewable energy from now on. The growth of the Russian power industry corresponds to the global trends in fossil energy consumption (while fossil prices, thus incomes keep worsening), and thus innovative solutions for enhancing renewable energies must be adopted. The article proves that many pipeline projects (South Stream, Turkish Stream, Nord Stream 2) move the Russian energy sector back to the past because they just contradict existing trends.

Ensuring the Economic Competitiveness of Small Green Energy Projects

2021 ◽  
pp. 28-40
Author(s):  
Iryna M. Sotnyk ◽  
Oleksandr M. Matsenko ◽  
Vladyslav S. Popov ◽  
Artem S. Martymianov
Keyword(s):  
Renewable Energy ◽  
Energy Generation ◽  
High Energy ◽  
Green Energy ◽  
Government Support ◽  
Energy Market ◽  
Poor People ◽  
Energy Pricing ◽  
Energy Technologies ◽  
Energy Projects

Small green energy projects are considered an important tool to help poor people achieve sustainable development goals. However, green projects' economic results do not always compete with the traditional energy business. The main reason is the imperfection of the existing renewable energy technologies and the comparatively high energy generation cost with their help. The example of Ukraine, which significantly depends on fossil fuel import and develops renewable energy with state support, shows that green energy competitiveness problems exist within the overall energy market, i.e., convenient energy technologies. The key barriers to increasing the competitiveness of small green energy projects are the lack of available financial resources, the inconsistency of state energy policy, energy pricing gaps, etc. These factors significantly inhibit the spread of green energy technologies in the domestic economy. The competitiveness assessment of the renewable energy business model on the example of a private rooftop solar photovoltaic power plant has proved that green energy generation is available to every household and small business owner and is economically profitable due to existing government support mechanisms. Today, there is no competition in the Ukrainian renewable energy market, so creating a business in this field is relevant. In the long run, competitive green energy projects will provide reasonable electricity prices for consumers and profits for energy producers and stimulate the energy sector's decarbonization. Further directions for improving public policy in the green energy industry are continuing energy pricing reforms, expanding energy efficiency programs focusing on demand management, creating new jobs, and increasing investment in renewable energy sources to ensure energy security and greenhouse gas emission reduction.

scholarly journals Application technology solar thermal power plant in Al-Kut

2021 ◽  
Vol 263 ◽  
pp. 05019
Author(s):  
Svetlana Sheina ◽  
Murtadha Muhsin ◽  
Lidiya Girya
Keyword(s):  
Renewable Energy ◽  
Carbon Dioxide Emissions ◽  
Fossil Fuels ◽  
Oil And Gas ◽  
Thermal Power ◽  
Solar Thermal ◽  
Solar Thermal Energy ◽  
Energy Evaluation ◽  
Clean Environment ◽  
Energy Projects

In this research, we study the operation and challenges of a renewable energy facility in the city of Kut, in central Iraq, which is common in Iraq, the electricity is generating from oil and gas which are harmful to the environment. In the article we have made a detailed study on power generation by relying on sunlight and the water of the Tigris River (the most famous river in Iraq). The article aims to develop detailed solutions to obtain energy without harming the environment by converting solar thermal energy into kinetic energy to generate the steam needed to rotate turbines during the day. And stored energy for use at night. The research shows the results of renewable energy evaluation and technology management in Iraq. To reduce the carbon dioxide emissions resulting from the combustion of fossil fuels to maintain a safe and clean environment. The world today has already begun to turn to this type of energy, and Iraq is one of the first countries in the Middle East, which has a good climate and record conditions for the success of renewable energy projects, technology renewable energy projects in Iraq is a must, given our lack of such important projects in the public interest.

Renewable Energy on Tribal Lands: A Feasibility Study for a Biomass-to-Energy Plant on the Cocopah Reservation in Arizona

2019 ◽  
Vol 3 (1) ◽  
pp. 1-12
Author(s):  
Lauren K. D’Souza ◽  
William L. Ascher ◽  
Tanja Srebotnjak
Keyword(s):  
Renewable Energy ◽  
Alternative Energy ◽  
Renewable Energy Sources ◽  
The United States ◽  
Biomass Energy ◽  
Policy Support ◽  
Small Scale ◽  
Energy Plant ◽  
Energy Projects ◽  
Alternative Investment

Native American reservations are among the most economically disadvantaged regions in the United States; lacking access to economic and educational opportunities that are exacerbated by “energy insecurity” due to insufficient connectivity to the electric grid and power outages. Local renewable energy sources such as wind, solar, and biomass offer energy alternatives but their implementation encounters barriers such as lack of financing, infrastructure, and expertise, as well as divergent attitudes among tribal leaders. Biomass, in particular, could be a source of stable base-load power that is abundant and scalable in many rural communities. This case study examines the feasibility of a biomass energy plant on the Cocopah reservation in southwestern Arizona. It considers feedstock availability, cost and energy content, technology options, nameplate capacity, discount and interest rates, construction, operation and maintenance (O&M) costs, and alternative investment options. This study finds that at current electricity prices and based on typical costs for fuel, O&M over 30 years, none of the tested scenarios is presently cost-effective on a net present value (NPV) basis when compared with an alternative investment yielding annual returns of 3% or higher. The technology most likely to be economically viable and suitable for remote, rural contexts—a combustion stoker—resulted in a levelized costs of energy (LCOE) ranging from US$0.056 to 0.147/kWh. The most favorable scenario is a combustion stoker with an estimated NPV of US$4,791,243. The NPV of the corresponding alternative investment is US$7,123,380. However, if the tribes were able to secure a zero-interest loan to finance the plant’s installation cost, the project would be on par with the alternative investment. Even if this were the case, the scenario still relies on some of the most optimistic assumptions for the biomass-to-power plant and excludes abatement costs for air emissions. The study thus concludes that at present small-scale, biomass-to-energy projects require a mix of favorable market and local conditions as well as appropriate policy support to make biomass energy projects a cost-competitive source of stable, alternative energy for remote rural tribal communities that can provide greater tribal sovereignty and economic opportunities.

PROSPECTS OF OBTAINING ALTERNATIVE FUEL FROM VARIOUS BIOMASS AND WASTE SPECIES IN AZERBAIJAN

2019 ◽  
pp. 25-41
Author(s):  
O. M. Salamov ◽  
F. F. Aliyev
Keyword(s):  
Power Plants ◽  
Energy Intensity ◽  
Oil And Gas ◽  
Renewable Energy Sources ◽  
Calorific Value ◽  
High Energy ◽  
Energy Sector ◽  
Energy Sources ◽  
Mineral Fertilizers ◽  
Gaseous Fuels

The paper discusses the possibility of obtaining liquid and gaseous fuels from different types of biomass (BM) and combustible solid waste (CSW) of various origins. The available world reserves of traditional types of fuel are analyzed and a number of environmental shortcomings that created during their use are indicated. The tables present the data on the conditional calorific value (CCV) of the main traditional and alternative types of solid, liquid and gaseous fuels which compared with CCV of various types of BM and CSW. Possible methods for utilization of BM and CSW are analyzed, as well as the methods for converting them into alternative types of fuel, especially into combustible gases.Reliable information is given on the available oil and gas reserves in Azerbaijan. As a result of the research, it was revealed that the currently available oil reserves of Azerbaijan can completely dry out after 33.5 years, and gas reserves–after 117 years, without taking into account the growth rates of the exported part of these fuels to European countries. In order to fix this situation, first of all it is necessary to use as much as possible alternative and renewable energy sources, especially wind power plants (WPP) and solar photovoltaic energy sources (SFES) in the energy sector of the republic. Azerbaijan has large reserves of solar and wind energy. In addition, all regions of the country have large reserves of BM, and in the big cities, especially in industrial ones, there are CSW from which through pyrolysis and gasification is possible to obtain a high-quality combustible gas mixture, comprising: H2 + CO + CH4, with the least amount of harmful waste. The remains of the reaction of thermochemical decomposition of BM and CSW to combustible gases can also be used as mineral fertilizers in agriculture. The available and projected resources of Azerbaijan for the BM and the CSW are given, as well as their assumed energy intensity in the energy sector of the republic.Given the high energy intensity of the pyrolysis and gasification of the BM and CSW, at the present time for carrying out these reactions, the high-temperature solar installations with limited power are used as energy sources, and further preference is given to the use of WPP and SFES on industrial scale.

scholarly journals Designing high energy density flow batteries by tuning active-material thermodynamics

RSC Advances ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 5432-5443
Author(s):  
Shyam K. Pahari ◽  
Tugba Ceren Gokoglan ◽  
Benjoe Rey B. Visayas ◽  
Jennifer Woehl ◽  
James A. Golen ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Energy Storage ◽  
Energy Density ◽  
Fossil Fuels ◽  
Active Material ◽  
High Energy ◽  
Theoretical Framework ◽  
High Energy Density ◽  
Density Flow ◽  
The Cost

With the cost of renewable energy near parity with fossil fuels, energy storage is paramount. We report a breakthrough on a bioinspired NRFB active-material, with greatly improved solubility, and place it in a predictive theoretical framework.

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