Model for evaluation of technical and economic indicators of offshore wind farms

THE PURPOSE. An urgent problem in the development of offshore wind energy is the high cost of generating electricity, which is due to large capital investments. The solution to this problem is possible by increasing efficiency while reducing costs as much as possible, which requires optimal design of offshore wind farms.

GOAL. Development of model for the technical and economic indicators of offshore wind farms based on configuration data, taking into account the factors of climatic conditions and the topography of the seabed at the site of the planned wind farm location.

METHODS. Mathematical modeling using Matlab software environment.

RESULTS. The model evaluates the impact of wake and electrical losses in the main components of the electrical system on the operation of an offshore wind farm, and also allows to take into account the influence of the seabed relief on the economic characteristics of wind turbine foundations. The model was tested on the example of calculating two existing offshore wind farms «Horns Rev 1» and «Horn Rev 2» by comparing the calculated indicators of the average annual electricity generation, capacity factor, capital expenditures and normalized cost of electricity with the actual indicators obtained during their operation. The comparison results show slight deviations within 5% of the actual values.

CONCLUSION. The model for assessing the technical and economic indicators of offshore wind farms was developed and tested on the basis of data on the wind farm configuration and layout, as well as factors of climatic conditions and terrain. Evaluation of the computational speed showed a sufficiently high efficiency of the algorithm, which allows the model to be applied to optimize large offshore wind farms.

1. Breeze P. Wind Power Generation. Academic Press. 2015. 104 p. https://doi.org/10.1016/C2014-0-04850-2.

2. U.S. Energy Information Administration’s Annual Energy Outlook 2021. Levelized cost and levelized avoided cost of new generation resources. Available at: https://www.eia.gov/outlooks/aeo/pdf/electricity_generation.pdf. Accessed: 10 December, 2021.

3. Tarovik V.I., Val'dman N.A., Trub M.S., et al. Razvitie morskih elektrostancij ispol'zuyushchih vozobnovlyaemye istochniki energii. Arktika: ekologiya i ekonomika. 2013; 2(10):34-47.

4. Global Wind Energy Council. Global offshore wind report 2020 Available at: https://gwec.net/global-offshore-wind-report-2020. Accessed: 10 December, 2021.

5. Kudelin A., Kutcherov V. Wind ENERGY in Russia: The current state and development trends. Energy Strategy Reviews. 2021; 34:100627. doi: 10.1016/j.esr.2021.100627.

6. Val'dman N.A., Trub M.S., Ozerova L.L. Morskie vetrovye elektrostancii. Trudy CNII im. akad. A.N. Krylova. 2015; 86(370):209-220.

7. Hou P., Zhu J., Ma K., et al. A review of offshore wind farm layout optimization and electrical system design methods. Journal of Modern Power Systems and Clean Energy. 2019; 7:975-986. doi: 10.1007/s40565-019-0550-5.

8. Rodrigues S., Restrepo С., Katsouris G., et al. A Multi-objective optimization framework for offshore wind farm layouts and electric infrastructures. Energies. 2016; 9(3):216. doi: 10.3390/en9030216.

9. Lumbreras S., Ramos A. Offshore wind farm electrical design: a review. Wind Energy. 2012; 16(3):459-473. doi: 10.1002/we.1498.

10. Tarovik V.I., Val'dman N.A., Trub M.S., et al. Uchet riskov pri stroitel'stve i ekspluatacii vetryanoj elektrostancii dlya Arktiki. Arktika: ekologiya i ekonomika. 2013; 3(11):84-96.

11. O’Kelly B.C., Arshad M. Offshore wind turbine foundations – analysis and design. Offshore Wind Farms: Technologies, Design and Operation. Ed. by C. Ng and L. Ran. Duxford: Woodhead Publishing. 2016. pp. 589-610.

12. Li J., Wang G., Li Z., et al. A review on development of offshore wind energy conversion system. International Journal of Energy Research. 2020; 44(12):9283-9297. doi: 10.1002/er.5751.

13. Katsouris G. Infield cable topology optimization of offshore wind farms [master of science thesis]. Delft, Netherlands: Delft University of Technology; 2015. Available at: http://resolver.tudelft.nl/uuid:9f313e13-4570-48f8-8aff-3eef35bbad99. Accessed: 10 December, 2021.

14. Katic I., Hojstrup J., Jensen N. A simple model for cluster efficiency. EWEC'86: European Wind Energy Association Conference and Exhibition Proceedings V.1; 6-8 Oct 1986; Rome, Italy. 1987. pp. 407-410.

15. Feng J., Shen W.Z. Solving the wind farm layout optimization problem using random search algorithm. Renewable Energy. 2015; 78:182-192. doi: 10.1016/j.renene.2015.01.005.

16. Davydov D.Y., Obuhov S.G. Optimizaciya raspolozheniya vetroustanovok s uchetom aerodinamicheskogo vzaimovliyaniya i protyazhennosti kabel'nyh linij seti sbora moshchnosti. Energosberezhenie i Vodopodgotovka. 2020; 3(125):30-34.

17. Dicorato M., Forte G., Pisani M., et al. Guidelines for assessment of investment cost for offshore wind generation. Renewable Energy. 2011; 36(8):2043-2051. doi: 10.1016/j.renene.2011.01.003.

18. Kucuksari S., Erdogan N., Cali U. Impact of electrical topology, capacity factor and line length on economic performance of offshore wind investments. Energies. 2019; 12(16):3191. doi: 10.3390/en12163191.

19. Lundberg S. Performance comparison of wind park configurations. Technical report no. 30R. Sweden: Chalmers University of technology; 2003. Available at: https://core.ac.uk/download/pdf/70559221.pdf. Accessed: 8 January 2022.

20. Davydov D.Y., Obuhov S.G. Wind speed model based on fractional stochastic process. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering. 2021; 332(5):39-48. (In Russ). doi: 10.18799/24131830/2021/5/3184.

21. General Bathymetric Chart of the Oceans (GEBCO). Gridded Bathymetry Data. Available at: https://www.gebco.net/data_and_products/gridded_bathymetry_data/. Accessed: 10 December, 2021.

22. Mokhi C.E., Addaim A., Cali U. Optimization of Wind Turbine Interconnections in an Offshore Wind Farm Using Metaheuristic Algorithms. Sustainability. 2020; 12(14):5761. doi: 10.3390/su12145761.

23. Gerdes G., Tiedemann A., Zeelenberg S. Case study: European offshore wind farms - A Survey for the analysis of the experiences and lessons learnt by developers of offshore wind farms. Report by Deutsche WindGuard. Groningen: University of Groningen; 2008. Available at: https://tethys.pnnl.gov/sites/default/files/publications/A_Survey_for_the_Analysis_by_Developers_of_Offshore_Wind_Farms.pdf. Accessed: 10 December, 2021.

24. Sharples M. Offshore electrical cable burial for wind farms: state of the art, standards and guidance & acceptable burial depths, separation distances and sand wave effect. Bureau of Ocean Energy Management, Regulation & Enforcement - Department of the Interior; 2011. Available at: https://www.bsee.gov/sites/bsee.gov/files/tap-technical-assessment-program//finalreport-offshore-electrical-cable-burial-for-wind-farms.pdf. Accessed: 10 December, 2021.

25. Lindoe Offshore Renewables Center knowledge. Offshore Renewables Map - Offshore Wind Farms. Available at: https://web.archive.org/web/20120116162257/http://www.lorc.dk/Knowledge/Offshorerenewables-map/Offshore-wind-farms. Accessed: 10 December, 2021.

26. Energy Numbers. Capacity factors at Danish offshore wind farms. Available at: https://energynumbers.info/capacity-factors-at-danish-offshore-wind-farms. Accessed: 10 December, 2021.

27. 4C Offshore. Global Offshore Wind Farm Database. Available at: https://www.4coffshore.com/windfarms/. Accessed: 10 December, 2021.

28. The Kingfisher Information Service – Offshore Renewable & Cable Awareness project (KIS-ORCA). Available at: https://kis-orca.org/downloads/. Accessed: 10 December, 2021.

29. Weather schedule RP5. Available at: https://rp5.md/Weather_archive_in_Blavand. Accessed: 10 December, 2021.

30. Spera D.A., Richards T.R. Modified power law equations for vertical wind profiles. Proceedings of the Conference and Workshop on Wind Energy Characteristics and Wind Energy Siting; 19-21 June 1979; Portland, Oregon (USA). Battelle Memorial Institute, Pacific Northwest Laboratory; 1979. pp. 47-58.

31. Réthoré P.E., Hansen K.S., Barthelmie R.J., et al. Benchmarking of wind farm scale wake models in the EERA - DTOC project. ICOWES 2013: Proceedings of the 2013 International Conference on Aerodynamics of Offshore Wind Energy Systems and Wakes; 17-19 June 2013; Lyngby, Denmark. Technical University of Denmark; 2013. Available at: https://backend.orbit.dtu.dk/ws/files/69802341/BENCHMARKING_OF_WIND_FARM_SCALE.pdf. Accessed: 10 December, 2021.