Development of an Economic and Efficient Installation Vessel for Tidal Stream Energy Converter Arrays

2013 ◽  
Author(s):  
Rachel Nicholls-Lee ◽  
Simon Hindley ◽  
Richard Parkinson
Keyword(s):  
Oil And Gas ◽  
Cost Effective ◽  
Concept Design ◽  
Market Place ◽  
Operations And Maintenance ◽  
Tidal Turbine ◽  
Tidal Stream ◽  
Tidal Stream Energy ◽  
Time Required ◽  
The Cost

In order for tidal stream technology to develop into a viable and cost effective energy solution, the overall cost of tidal array installation, operations and maintenance must be driven down. The key issues which drive the cost are the time required to conduct operations and susceptibility to weather risk coupled with the expense of marine assets. Current vessels have limited operational windows due to weather and tidal constraints, which result in considerable cumulative costs due to high charges for such vessels. The marine renewable industry is currently reliant on vessels of opportunity from the offshore oil and gas sector; which, while sufficient for single device demonstration deployments, are not viable for array installations. De-coupling the tidal sector from this market place offers the opportunity to reduce the volatility of vessel day rates. This paper presents the concept design of an efficient and economic, fit for purpose installation vessel for tidal stream energy converters. The vessel has good dynamic positioning capabilities for operation in strong tidal currents thus broadening the operational window. The environmental impact of the vessel is reduced when compared to existing vessels. A key criterion throughout the design process is minimizing the cost of the vessel to tidal turbine site developers.

Inspection Manpower Planning for X & S Control Charts

2012 ◽  
Vol 488-489 ◽  
pp. 1624-1630
Author(s):  
Wen An Yang ◽  
Wen He Liao ◽  
Yu Guo
Keyword(s):  
Control Charts ◽  
Cost Effective ◽  
Manpower Planning ◽  
Sampling Interval ◽  
Optimal Number ◽  
Optimization Strategy ◽  
Effective Manner ◽  
Time Required ◽  
The Cost ◽  
And Control

A method of determining the optimal number of inspectors and/or working time required on a specific SPC activity is presented in the study. The issue of inspection manpower planning is handled as a constrained optimization problem. The optimization strategy is not only to minimize the avoidable surplus quality loss due to failure of detecting the out-of-control states but to determine the cost of inspection manpower from the perspective of deploying an appropriate amount of inspection manpower in a cost-effective manner, and meanwhile the values of sample size, sampling interval and control limits of control charts are also determined. The result obtained indicates that the total cost (or loss) can be substantially reduced if implementing control charts was equipped with adequate inspection manpower.

scholarly journals A HOLISTIC METHOD TO SELECT TIDAL STREAM ENERGY HOTSPOTS

2017 ◽  
pp. 5
Author(s):  
Angela Vazquez ◽  
Gregorio Iglesias
Keyword(s):  
Ad Hoc ◽  
Holistic Approach ◽  
Tidal Energy ◽  
Energy Development ◽  
Potential Conflict ◽  
Cost Of Energy ◽  
Tidal Turbine ◽  
Tidal Stream ◽  
Tidal Stream Energy

Potential areas for tidal stream energy development are conventionally selected on the basis of resource assessments. For all the importance of the resource, there are other elements (technological, economic, spatial, etc.) that must be taken into account in this selection. The objective of the present work is to develop a new methodology to select tidal stream hotspots accounting for all these relevant elements, and to apply it to a case study, showing in the process how the potential for tidal energy development can be fundamentally altered by technological, economic and spatial constraints. The case study is conducted in the Bristol Channel and Severn Estuary (UK), one of the regions with the largest tidal resource in the world. First, the most energetic areas are identified by means of a hydrodynamics model, calibrated and validated with field data. Second, the method calculates the energy that can be harnessed in these areas by means of a geospatial Matlab-based program designed ad hoc, and on the basis of the power curve and dimensions of a specific tidal turbine. Third, the spatial distribution of the levelised cost of energy (LCOE) is calculated, and a number of locations are selected as potential tidal sites. The fourth element in the approach is the consideration of restrictions due to overlap with other marine uses, such as shipping. As a result, potential conflict-free areas for tidal stream energy exploitation at an economical cost are identified. Thus, the case study illustrates this holistic approach to selecting tidal stream sites and the importance of elements other than the resource, which – for all its relevance – is shown to not guarantee by itself the potential for tidal stream energy development.

Using Homer Software for Cost Analysis of Stand-Alone Power Generation for Small Scale Industry in Nigeria: A Case Study Lumatec Aluminium Products

2021 ◽  
Vol 2 (2) ◽  
pp. 90-102
Author(s):  
Luqman Raji ◽  
Zhigilla Y.I ◽  
Wadai J
Keyword(s):  
Power Generation ◽  
Cost Analysis ◽  
Oil And Gas ◽  
Cost Effective ◽  
Small Scale ◽  
Pv System ◽  
Rural And Urban ◽  
Small Scale Industry ◽  
The Cost ◽  
Small Scale Industries

Nigeria is one of developing countries in the world that experience shortage of electricity for her economic and social development. In Nigeria, most of the small-scale industries use diesel/petrol-based systems to generate their electricity. However, due to the cost fluctuation of oil and gas fuel, an alternative power generation should be considered. This paper targets to examine the cost analysis of system for supplying electricity to LUMATEC Aluminium products shop in Mubi, Adamawa state Nigeria. Hybrid Optimization Model for Electric Renewable (HOMER) is used as a tool for cost analysis. The scenario consider in this study was only stand-alone with battery system. Results revealed that the system have 10kW PV with cost of electricity (COE) of $0.312/kW. The initial capital cost and total net present cost (NPC) are $21.775 and $26.148 respectively, with payback period of 5.8years. In conclusion, this study provides the solution of power supply to the small-scale industries at cost effective and available throughout the year and it is feasible to solve the small-scale industries, rural and urban electricity supplying in this country (Nigeria). It is recommended that Nigerian Government & Law makers should promotes the use of standalone PV system for domestic and small-scale industry by providing financial assistance through soft loans, subsides and grants.

The Influence of Dose Frequency and Agent Toxicity on the Cost of Parenteral Antibiotic Therapy

1982 ◽  
Vol 16 (12) ◽  
pp. 935-938 ◽  
Author(s):  
Robert P. Rapp ◽  
Catherine L. Bannon ◽  
Brack A. Bivins
Keyword(s):  
Combination Therapy ◽  
Antibiotic Therapy ◽  
First Generation ◽  
Single Agent ◽  
Cost Effective ◽  
Generation Cephalosporin ◽  
Dose Frequency ◽  
Surgery Patient ◽  
Time Required ◽  
The Cost

The influence of the number of daily doses on the overall cost of antibiotic therapy is examined in a general surgery patient population. Patients receiving a single first-generation cephalosporin are compared with patients receiving two or three antibiotics (including an aminoglycoside) in terms of (1) the cost of the drug and the supplies, (2) time required for nursing and pharmacy personnel to prepare and administer the doses, and (3) the influence of agent toxicity (renal function) on physician-ordered laboratory tests. On the whole, combination therapy including an aminoglycoside was four times as expensive as single-agent (first-generation cephalosporin) therapy. If future studies demonstrate that single-agent antibiotic therapy is as effective as traditional combination therapy for specific infectious diseases, the influence of the number of daily doses of drug and agent toxicity may support the cost-effective use of the newer agents.

Demonstrating a Tidal Turbine Control Strategy at Laboratory Scale

2016 ◽  
Author(s):  
Magnus Harrold ◽  
Peter Bromley ◽  
Merin Broudic ◽  
David Clelland
Keyword(s):  
Control Strategy ◽  
Cost Effective ◽  
Scale Model ◽  
Turbine Performance ◽  
Controller Gain ◽  
Tidal Turbine ◽  
Tidal Stream ◽  
Commercial Device ◽  
Tidal Stream Turbine ◽  
Thrust Forces

Ahead of the installation of a commercial tidal stream turbine, a 1:30 scale model of the device was tested in a recirculating flume tank. This proved to be the first physical demonstration of the turbine’s unconventional control strategy, which limits the thrust forces on the device by allowing the rotor to enter an overspeed. The tests showed that this simple to implement concept of operation is a cost-effective and reliable means of managing the rotor thrust loads in energetic flows. Subsequent tests highlighted the importance of correctly calculating the controller gain parameter, otherwise detrimental turbine performance characteristics can be expected. When relating these results to that of the commercial device, there are a number of important differences associated with both the environment and scale of the model tests. Despite this, the results are considered encouraging, and provided confidence for the full-scale deployment.

Testing Device for Hydrodynamic Characteristic on Conversion Devices of Tidal Stream Energy

2010 ◽  
Author(s):  
Li Long ◽  
Wang Ze ◽  
Zhou Kaining ◽  
Li Bo
Keyword(s):  
Energy Conversion ◽  
Hydrodynamic Model ◽  
Hydrodynamic Characteristic ◽  
Cost Effective ◽  
Electrical Energy ◽  
Testing Device ◽  
Essential Condition ◽  
Tidal Stream ◽  
Tidal Stream Energy ◽  
Conversion Technology

The feasibility of tidal in stream energy conversion technology, especially the demonstration of the efficiency in energy conversion, is of consequence to provide efficient devices and cost-effective electrical energy. The excellent hydrodynamic model of the conversion devices is an essential condition of a successful tidal flowing power. The experimentation of the hydrodynamic model in laboratory should be first selecting by reason of the reliability and immediate data to assess the hydrodynamic characteristic. But, the simulation of a flowing condition in laboratory is not easily accomplished, as a result of need of bigger flowing speed and greater bigger flume. Based on the relativity principle, the relative testing method of the energy conversion technology in tidal stream was provided. The peculiarity, the structure of the testing device was indicated. The function of every composing proportion on the testing device was explained. The process of experimentation was introduced.

scholarly journals Hydrophone VSP surveys in hard rock

Geophysics ◽  
2012 ◽  
Vol 77 (5) ◽  
pp. WC223-WC234 ◽  
Author(s):  
Andrew Greenwood ◽  
Christian J. Dupuis ◽  
Milovan Urosevic ◽  
Anton Kepic
Keyword(s):  
Hard Rock ◽  
Cost Effective ◽  
Mine Planning ◽  
Data Sets ◽  
Successful Case ◽  
Seismic Acquisition ◽  
Deployment Time ◽  
Time Required ◽  
Operational Issues ◽  
The Cost

Seismic imaging in hard rock environments is gaining wider acceptance as an exploration technique and as a mine-planning tool. To date, 13 successful case studies have been acquired in Australia. The images generated from hard rock targets exhibit large levels of complexity and their interpretations remain an active area of study. To assist the imaging and better understand the source of the reflections observed, vertical seismic profiling (VSP) can be employed. This technique is not readily applied to hard rock environments because cost and operational issues often prove prohibitive. We propose the use of hydrophone arrays as a cost effective solution to VSP acquisition. We highlight the key challenges in using these receivers and propose solutions to overcome them. By careful acquisition methodologies and refined signal processing techniques, the tube waves that have up to now compromised the use of hydrophones for VSP acquisition can be effectively mitigated. We show that the data acquired with hydrophones compare favorably to that acquired with conventional 3C geophones. The data acquired with hydrophones come at a fraction of the cost and deployment time required for conventional acquisition procedures. Our results show that hydrophone vertical seismic acquisition is a viable, cost effective, and efficient solution that should be employed more routinely in hard rock environments to enhance the value of the surface data sets being acquired.

The effect of collector size on forest litter-fall collection and analysis

1983 ◽  
Vol 13 (6) ◽  
pp. 1037-1042 ◽  
Author(s):  
M. C. McShane ◽  
D. W. Carlile ◽  
W. T. Hinds
Keyword(s):  
Cost Effective ◽  
Forest Litter ◽  
Litter Fall ◽  
Laboratory Sample ◽  
Large Numbers ◽  
The Mean ◽  
Definition Of ◽  
Time Required ◽  
The Cost ◽  
Sample Sorting

Litter fall is commonly collected for a variety of ecological studies. This study was designed to test the effect of collector size on the precision of forest litter-fall estimates and on the time involved in laboratory sample sorting. Collectors varied in size from 0.010 to 0.933 m2 and were physically nested, the smaller units within larger units. Ten of these collector combinations were randomly placed on a 1-ha plot in a Douglas-fir/western hemlock (Pseudotsugamenziesii (Mirb.) Franco/Tsugaheterophylla (Raf.) Sarg.) stand in H. J. Andrews Experimental Forest. Collections were made monthly and records were kept of the time required to sort the litter into needles, epiphytes, and miscellaneous categories. Based on a definition of precision as ±10% of the mean, 90% of the time, results indicate (i) that the cost of obtaining precise estimates of needle fall decreases with decreasing collector size to 0.010 m2, (ii) that collectors of any size can be used to obtain estimates of total litter fall if the number of collectors required to obtain precise results is determined, and (iii) that precise estimates of epiphyte biomass require large numbers of samplers and are not cost effective.

Parametric Investigation of the Stability of Vessels for Float-Over Deck Transportation

2002 ◽  
Author(s):  
Lee O’Neill ◽  
Shaun O’Brein ◽  
Emmanuel Fakas
Keyword(s):  
Oil And Gas ◽  
Cost Effective ◽  
High Elevation ◽  
Accurate Analysis ◽  
Large Size ◽  
Wide Range ◽  
Transport Vessel ◽  
The Stability ◽  
The Cost ◽  
Vessel Stability

The technical challenge of transporting large size integrated decks, especially float-over decks at high elevation, is well recognised. The cost of such operation usually forms a significant part of the overall development cost, especially in remote parts of the world where the transport routes are longer and the transport vessel choice is limited. In this respect, suitable vessel selection is very critical in terms of the economic viability of oil and gas developments, especially of marginal fields. A cost-effective working method is developed for selecting suitable vessels for a wide range of transport options (deck weights and transport elevations) without the requirement of extensive analyses. This method may be used at the very early stages of any study to assess the feasibility of the transport concept and also provide a wider choice of feasible options to be considered at the next stage of the development, where a more accurate analysis may be justified. Some potential ways for improving vessel stability are also investigated. Findings from the study can also be applied to integrated deck salvage transport.

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