One of the most important problems of the Estonian energy system is the compensation of power fluctuations of wind parks. The possibilities of energy system stabilization by Estonian oil shale power plants are limited. At the same time the use of wind energy has not led to the expected reduction in oil shale consumption. Autonomous wind energy systems with some storage devices are one possible way to develop wind energy usage. A system consisting of a wind generator and storage device is analyzed in this article. The storage device might be a fuel cell with hydrogen storage, pumped storage, flywheel or battery. A unit generator and the normalized and averaged power curve of small wind turbine generators are used for the analysis of wind data. Average hourly wind speeds are measured in different locations of Estonia. The duration, frequency and distribution of windless time periods are analyzed. The estimated principles of storage device selection are given according to wind data and power curves.
1. Estonian Standard. EVS-EN 61400-2:2006. Wind Turbines. Part 2: Design Requirements for Small Wind Turbines. 2006. 179 p.
2. Valdma, M., Keel, M., Tammoja, H., Kilk, K. Reliability of electric power generation in power systems with thermal and wind power plants // Oil Shale. 2007. Vol. 24, No. 2S. P. 197–208.
3. Kalamees, T., Kurnitski, J. Estonian test reference year for energy calculations // Proc. Estonian Acad. Sci. Eng. 2006. Vol. 12, No. 1. P. 40–58.
4. Kull, A. Estonian Wind Atlas. Master’s thesis. University of Tartu, Institute of Geography, Tartu, 1995.
5. Oidram, R., Tammoja, H., Keel, M., Palu, I. Wind power cooperation with energy storing units and cogeneration power plants // Security and Reliability of Electric Power Systems, CIGRE Regional Meeting June 18–20, 2007. Tallinn, Estonia. P. 15–21.
6. Keel, M., Liik, O., Tammoja, H., Valdma, M. Optimal planning of generating units in power system considering uncertainty of information // Oil Shale. 2005. Vol. 22, No. 2S. P. 97–107.
7. Keel, M., Tammoja, H., Valdma, M. Optimal operation of power plants in cogeneration systems // Oil Shale. 2005. Vol. 22, No. 2S. P. 109–117.
8. Liik, O., Oidram, R., Keel, M., Ojangu, J., Landsberg, M., Dorovatovski, N. Co-operation of Estonia’s oil shale based power system with wind turbines // Oil Shale. 2005. Vol. 22, No. 2S. P. 127–142.
9. Liu,X., Islam, S. Reliability Evaluation of a wind-diesel hybrid power system with battery bank using discrete wind speed frame analysis // 9th International Conference on Probalistic Methods Applied to Power Systems. Stockholm: KTH, 2006. 7 p.
10. Kaldellis, J. K. An integrated model for performance simulation of hybrid wind-diesel systems // Renew. Energy. 2007. Vol. 32, No.9. P. 1544–1564.
11. Tomson, T., Annuk, A. Wind energy in Estonian farmland // CIGR E-Journal (1-10) / Dr. Lingjuan Wang (ed.). – North Carolina: North Carolina State University, 2005.
12. Annuk, A., Tomson, T. About wind capacity in South-Eastern Estonia // Investigation and Usage of Renewable Energy Sources: Sixth conference proceedings / V. Tiit (ed.). – Tartu: Halo, 2005. P. 112–118 [in Estonian].
13. Annuk, A., Kokin, E., Palge, V., Põder, V., Lepa, J. Wind energy application problems in inland areas of Estonia // Agronomy Research. 2008. Vol. 6, Special issue. P. 169–180.
