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You searched for subject:(o m cost). Showing records 1 – 3 of 3 total matches.

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1. Cantu, Hector Trevino. Life-Cycle Cost Analysis for Offshore Wind Farms:Reliability and Maintenance.O&M Cost Drivers Analysis.

Degree: Energy and Environment, 2011, Gotland University

Operations and maintenance (O&M) activities represent a significant share of the expenses during the lifetime of offshore wind farms. When compared to onshore wind farms, O&M costs are increased for the offshore case, as specialized vessels, weather windows and rough conditions mean more failures, downtime (decreasing availability), spare parts, and man-hours.This study comprises an analysis of the available O&M data from a selected offshore wind farm. The results and conclusions from this investigation could then be used to evaluate possible reliability improvements and compare options for the maintenance strategies, as well as to ponder the convenience of warranty periods and O&M agreements between wind farm operators and wind turbine manufacturers or O&M service providers.The life-cycle cost (LCC) concept is utilized in the analysis of the wind farm survey for this thesis. LCC analysis could be the starting point to make decisions regarding specific wind turbine models, as selecting the turbines with the lowest initial cost may not be necessarily the scenario which also costs the least amount of money when taking into consideration the whole life cycle. It may also be a great tool to forecast future operational incomes and expenses of offshore wind farms.

Subjects/Keywords: Offshore; wind farm; operations; maintenance; O&M; life-cycle cost; reliability.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Cantu, H. T. (2011). Life-Cycle Cost Analysis for Offshore Wind Farms:Reliability and Maintenance.O&M Cost Drivers Analysis. (Thesis). Gotland University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217018

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Cantu, Hector Trevino. “Life-Cycle Cost Analysis for Offshore Wind Farms:Reliability and Maintenance.O&M Cost Drivers Analysis.” 2011. Thesis, Gotland University. Accessed December 05, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217018.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Cantu, Hector Trevino. “Life-Cycle Cost Analysis for Offshore Wind Farms:Reliability and Maintenance.O&M Cost Drivers Analysis.” 2011. Web. 05 Dec 2019.

Vancouver:

Cantu HT. Life-Cycle Cost Analysis for Offshore Wind Farms:Reliability and Maintenance.O&M Cost Drivers Analysis. [Internet] [Thesis]. Gotland University; 2011. [cited 2019 Dec 05]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217018.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cantu HT. Life-Cycle Cost Analysis for Offshore Wind Farms:Reliability and Maintenance.O&M Cost Drivers Analysis. [Thesis]. Gotland University; 2011. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-217018

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation


Delft University of Technology

2. Neutink, K. Probabilistic design of operations and maintenance on offshore wind energy conversion systems:.

Degree: Civil Engineering and Geosciences, Hydraulic Engineering, 2001, Delft University of Technology

The demand for energy is still increasing, together with the desire to create more durable solutions. Wind energy is currently one of the most promising ways to provide both. A shortage of suitable land sites was the main reason for considering the location of the wind farms offshore, which also offers higher wind speeds. A problem however is formed by the low accessibility during periods of high wind speeds. This low accessibility could lead to a decrease in availability of the system and high O&M cost, both unfavourable for the levelised production cost and thus the profitability of the system. The levelised production costs have long been used as the main criterion in the evaluation of a farm design. In a private energy market, the system however should be optimised to maximise profit. At present energy prices the difference this gives for the optimisation of the farm and its O&M can be neglected. The goal of this thesis is the optimisation of operations and maintenance on Offshore Wind Energy Conversion Systems with a probabilistic model. A number of previously executed studies were used to determine what input parameters should playa role. This showed that all subsystems contribute significantly to the initial capital cost, O&M cost and the unavailability of the system. The model should take into account that periods of low accessibility coincide with periods of high energy potential. The model is based on a state-space model of each component. A component can find itself in the states "Failed", "Corrective Maintenance", "Preventive Maintenance" or "Available". Each component in the system is part of the chain connection that transports the produced energy to shore. If this chain is broken by a failure the loss in production capacity is determined by the place of the component in the chain. The failure of a component is determined by a Monte Carlo simulation. The reliability of components decreases in time according to a certain decline rate. After the execution of PM or CM the initial reliability will be restored. The program, written in visual basic, shows results according to predictions by hand calculations and results from other studies. It can be used to optimise the system. A simulation of the base case showed that the turbines are the main cause of unavailability and cost. The main cost drivers of ICC are turbines and their support structure. As expected the main O&M costs are caused by the turbine and in particular the rotors. The turbines are also the main cause of unavailability: 7% compared to around 2% for the shore- and grid connection. There is a relationship between unavailability of the system and the occurrence of high wind speeds. It shows a decline in availability of about 5% for wind speeds higher than the wind limit of used O&M tools. This results in a loss of revenues of about 2% per year. The relationship between PM interval, failure- and decline rate has been investigated. The first results indicate a trend towards a decreased need for PM than the intervals used in the base case. The… Advisors/Committee Members: Vrijling, J.K., Veraart, C., Van Bussel, G.J.W., Van der Meulen M., Van Gelder, P.H.A.J.M., Hydronamic bv.

Subjects/Keywords: wind energy; optimisation; o & m cost

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Neutink, K. (2001). Probabilistic design of operations and maintenance on offshore wind energy conversion systems:. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:71f40a9c-4615-4c9d-9301-f7fb467395a3

Chicago Manual of Style (16th Edition):

Neutink, K. “Probabilistic design of operations and maintenance on offshore wind energy conversion systems:.” 2001. Masters Thesis, Delft University of Technology. Accessed December 05, 2019. http://resolver.tudelft.nl/uuid:71f40a9c-4615-4c9d-9301-f7fb467395a3.

MLA Handbook (7th Edition):

Neutink, K. “Probabilistic design of operations and maintenance on offshore wind energy conversion systems:.” 2001. Web. 05 Dec 2019.

Vancouver:

Neutink K. Probabilistic design of operations and maintenance on offshore wind energy conversion systems:. [Internet] [Masters thesis]. Delft University of Technology; 2001. [cited 2019 Dec 05]. Available from: http://resolver.tudelft.nl/uuid:71f40a9c-4615-4c9d-9301-f7fb467395a3.

Council of Science Editors:

Neutink K. Probabilistic design of operations and maintenance on offshore wind energy conversion systems:. [Masters Thesis]. Delft University of Technology; 2001. Available from: http://resolver.tudelft.nl/uuid:71f40a9c-4615-4c9d-9301-f7fb467395a3


University College Cork

3. Shanley, Matthew. Innovative hull design for servicing offshore wind turbines.

Degree: 2018, University College Cork

Accessing turbines for maintenance is a key operational issue for an offshore wind farm. Currently there is a 1.5m significant wave height (Hs) limit for the standard “step over” method of transferring personnel to an offshore wind turbine, though this varies with, vessel type, wave period and direction, as well as wind, and current conditions. The thesis aims to quantify limiting conditions for access, and increase the Hs at which offshore wind turbines can be accessed. This thesis investigated the motion of novel ship hull designs, and quantified parameters that influence the transfer of personnel from a wind farm service vessel (WFSV) to a wind turbine. To complete the work for this thesis numerical, and physical techniques were utilised to model WFSV designs at zero forward speed in open water, and when docked with an offshore wind farm monopile. When designs were being investigated particular attention was paid to novel hull geometry, and the addition of heaveplates to catamaran hulls. A directional study on WFSV interaction with a monopile was carried out, and polar plots of performance were calculated. The limits of motion that a safe transfer can take place from the literature were compared with those of a basic standard catamaran design, and were then used to assess novel designs. Critical issues at the monopile are, heave, surge, pitch, fender friction and bollard pull, for quartering and beam seas sway and roll are important. Heaveplates provide benefits, however increasing heave damping changes the principal fail condition from vertical slips to horizontal disconnects. Some of these failure cases could be predicted by vessel motion, which may be useful for a warning system. A vessel that can carry out transfers up to a 3.5m Hs was developed. Advisors/Committee Members: Murphy, James, Lewis, Anthony, HEA, SFI.

Subjects/Keywords: Offshore wind farm service vessel; WFSV; CTV; O&M; MII; P-Plot; Offshore; Wind farm service vessel; Crew transfer vessel; Operations and maintenance; Offshore wind energy; Motion induced interruption; Levelised cost of energy; Motion compensating gangway; Offshore renewable energy installation; Service operations vessel; Performance plot

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Shanley, M. (2018). Innovative hull design for servicing offshore wind turbines. (Thesis). University College Cork. Retrieved from http://hdl.handle.net/10468/5793

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Shanley, Matthew. “Innovative hull design for servicing offshore wind turbines.” 2018. Thesis, University College Cork. Accessed December 05, 2019. http://hdl.handle.net/10468/5793.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Shanley, Matthew. “Innovative hull design for servicing offshore wind turbines.” 2018. Web. 05 Dec 2019.

Vancouver:

Shanley M. Innovative hull design for servicing offshore wind turbines. [Internet] [Thesis]. University College Cork; 2018. [cited 2019 Dec 05]. Available from: http://hdl.handle.net/10468/5793.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Shanley M. Innovative hull design for servicing offshore wind turbines. [Thesis]. University College Cork; 2018. Available from: http://hdl.handle.net/10468/5793

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

.