Introduction to the projectDetailed instructions

16 different teams are asked to perform pre-feasibility studies for different wind power projects. The teams will be formed by the teacher. Below are some general information about the project. Detailed instructions are available from the menu on the left-hand side.¶ Team NameTotal Wind Farm Size [MW]Wind Turbine Size [kW]Wind Speed DataLocation Team 1 20 500-800 Set 1 Offshore Team 2 40 1000-2000 Set 1 Mountain Team 3 100 1000-2000 Set 1 Onshore Team 4 140 1500-2500 Set 2 Offshore Team 5 160 1000-2000 Set 2 Onshore Team 6 180 2500-3600 Set 2 Mountain Team 7 240 1500-2500 Set 2 Onshore Team 8 280 3000-5000 Set 2 Mountain Team 9 320 2500-3600 Set 2 Offshore Team 10 460 3000-5000 Set 3 Offshore Team 11 520 2500-3600 Set 3 Onshore Team 12 640 1500-2500 Set 3 Offshore Team 13 760 2500-3600 Set 3 Offshore Team 14 800 2000-3000 Set 3 Onshore Team 15 900 3000-5000 Set 3 Offshore Team 16 1000 3000-5000 Set 3 Onshore Links to the data sets:¶
* Set 1: http://www.eps.ee.kth.se/EG2040/Set1.xls
* Set 2: http://www.eps.ee.kth.se/EG2040/Set2.dat
* Set 3: http://www.eps.ee.kth.se/EG2040/Set3.dat
The project includes the following stages:¶
* A report with a maximum of 20 pages per team. An electronic copy must be sent to , by Friday 11 April 2014, 5 pm (17.00). You can find instructions for the report at the end of this document.
* Each report will be given to another team for opposition. All teams must send an electronic version of the opposition report to camille.hamon@ee.kth.se on Tuesday 22 April 2014, 5 pm. See below for instructions for the opposition.
* The teams update their report according to the comments received from the opposing team. A paper copy of the final report must be handed in in the course mailbox at Teknikringen 33 and an electronic copy sent to camille.hamon@ee.kth.se by Wednesday 30 April 2014, 5 pm.
* A team presentation of 10 – 15 minutes, which will be held on one of 12, 13, 14, 15 and 15 May 2014. The presentation will be followed by questions from the audience, and from another team which will have read the report and prepared questions. This means that every team will get a copy of the final report of another team, and should prepare questions on it beforehand..
Important deadlines¶ DateDescription 8 February The groups will be announced. 11 April, 17:00 Send an electronic copy of the report to camille.hamon@ee.kth.se 22 April, 17:00 Send the opposition report to camille.hamon@ee.kth.se 30 April, 17:00 Final report: Hand in a paper copy and send an electronic copy to camille.hamon@ee.kth.se 30 April – 7 May Register for the oral presentation: https://www.ee.kth.se/lab?course=EG2040 Instructions for the report¶ A portion of the final mark will depend on the structure and layout of the final report. The report must be written in English and should be well structured (it is advised to use the different tasks, sections A – E, as the different sections for the report). The layout should be consequent throughout the report. The page limit of 20 pages includes everything (title page, table of contents, main content, bibliography) but appendices.¶ The following elements must be found in your report:¶
* names of team participants,
* a table of contents,
* a summary,
* a list of all references: you have to give references for all figures and facts (for example electricity prices and prices to build the turbines), definitions of all symbols introduced in the calculations, page numbers.
Check this list before you hand in your report to make sure that your report fulfil these requirements. Please note that the reports will be run through an anti-plagiarism tool that searches for matches between the reports and sources available on the interneThis is a research exercise, so you should look outside the course material for further information. Books, journals, newspapers and internet, as well as personal and email communication with industry or academic experts are acceptable references. Reading reports from operational wind farms can help you understand the choices that have to be done. Complete tasks A – E, but also include anything you consider important and / or interesting for an investor, and stay within the page limit.¶

Task A: Analysis of Available Wind Turbine Technology¶

Instructions
* Compare the technical designs of four wind turbines from different wind turbine manufacturers. You can choose any turbines within the wind turbine rating limits defined for your team.¶


* Discuss the main features of the wind turbines, e.g. reactive power and fault ride through capabilities, power curves, weight etc., if available. Also discuss different foundation options and other issues related to the installation, e.g. issues related to the location.¶


* Choose two turbine models for further examination, and explain your reasons for choosing them.¶


Details from the comparison should be summarised within one table, and include a discussion of not more than two pages of text.¶

Hints Some wind turbine models can be found at¶


* http://www.wind-energie.de/en/¶


* http://www.windustry.org/your-wind-project/wind-energy-companies/wind-energy-companies¶


Task B: Wind Data Analysis¶

Instructions
* Siting:¶


* Nominate a possible location in the world that fits with the requirements for your group (onshore, offshore, mountain, see table above) for the wind power investment.¶


* Design two possible layouts for the wind farm. Each layout should take into account both the topological layout of the turbines, for example which direction they face and how they are sited with respect to each other, and the electrical layout, for example the main electrical components in the internal grid of the wind farm and the electrical connections between the turbines. Explain briefly why you have chosen the location and layouts, taking into account environmental aspects, grid connection aspects and economical aspects.¶



* Assume that the wind speed data specific for your group has been measured at this location (This means that you do not have to look for a location whose wind conditions match the data you are given.), at a height of 10 meters. Wind coming from the North has an angle of 0°, East of 90°, South of 180° and West of 270°. Calculate the annual energy production of the wind farm for the two layouts and the two wind turbine models chosen in Section A, by making appropriate assumptions about the wind turbine availability, the wake effect between the turbines, the tower height and the roughness factor (It is possible to use an invalid “trick” here: take two locations and the same measured wind speed data, the location with the highest roughness factor will get higher wind speeds because of the logarithmic profile. This is not a valid argument for choosing a location. In short: do not choose a location because its roughness factor gives rise to higher wind speeds with the given data.).¶


* Finally, for the rest of the study, choose a wind turbine from the two models you kept from Section A and a layout from the two you proposed and explain your choice.¶


Task C: Network Integration Issues¶

In this part, you are asked to choose a proper point to connect the wind farm to the grid. The grid that all teams will use for analysis of network integration is shown in the figure below (this is a schematic of the grid to which you will connect your wind farm). The data for each points to which the wind farm may be connected is given in the table below.¶

Network for project¶

Point NumberConnection PointShort-circuit Capacity Sk (MVA)Load/line/phase (A)Number of lines 1 T925 450 150-370 2 2 A10 800 150-390 4 3 20 kV side of T1 in M10 1000 130-345 2 4 B20 1200 130-345 2 5 70 kV side of T2 in T57 1200 130-345 2 6 70 kV side of 200/70 kV transformer 1700 120-325 1 7 200 kV side of 200/70 kV transformer 2000 42-114 2 8 Strong grid – 84-228 1 The following assumptions can be made for the calculations:¶


* the grid can be assumed to be purely inductive,
* load power factor can be assumed 0.9 inductive everywhere,
* the installed wind farm is controlled to keep a power factor equal to 1, voltage limits are +/- 10% for voltages above and including 70 kV, and -10%, +6% for voltage levels below 70 kV,
* the higher the short-circuit capacity of the connection point the higher the price for connection at this point.
Instructions
* Calculate the maximum capacity of a wind farm that can be connected to each of the connection points.
* Choose a location in the network where it is possible and most economically efficient to install your wind farm. Include all calculations and relevant curves which support your choice.
* What other issues need to be considered when choosing a connection point?
* What would happen if the wind farm was able to generate reactive power? Assume that the power factor of the wind farm is 0.95, and calculate the maximum capacity of the wind farm that can be connected in this case.
Notes and hints
* The voltage limits are given in terms of the nominal voltages, which are given by the transformer ratings.
* The network at every connection point can be represented by a Thévenin equivalent. The nominal voltages can be used for Thévenin voltages Uth.
* The load currents are given per line and per phase in table above. The total load is calculated approximately as S = n \sqrt{3} U_{th} I_{load} where n is the number of lines. From this P_{load} and Q_{load} are calculated as in Assignment 2.
* Also, the load currents given in the table above can take on all values in the given range, not just the extreme values.
* It is not enough to only consider the lowest load values.
* Using the simplifications above, the network can be simplified to a two node equivalent, and the voltage can be calculated using equation (5.29) from Static Analysis of Power Systems.
Task D: Economic Analysis¶

Instructions
* Describe, if any, the support scheme for wind power that is used at the location you chose.
* Calculate the life cycle costs of your project over a lifetime of 20 years. Include the cost of equipment, installation, maintenance, dismantling etc. in your analysis and make appropriate assumptions about the price of the power. Do not forget to include incomes from support schemes.
* Include a sensitivity analysis and summarize your findings.
Notes and hints It is strongly advised to use the software RETScreen to do the economic analysis. RETScreen is a free Excel-based program and can be found at http://www.retscreen.net. It requires Windows and Excel. It is available in the student room at Teknikringen 33 (H building).¶

Task E: Discussion¶

Discuss the feasibility of your project.