الفهرس 
RELIABILITY OF POWER SYSTEMS INCLUDING WG
Methodology proposed in the studyOnly 14 pages are availabe for public view
 |  | from | 111 |  |  |
| | | from | 111 | | |
Abstract
This thesis introduces a reliability-based methodology to evaluate the capacity credit of the wind energy conversion system resulted from the integration of this wind energy to the power systems. A computational model has been developed for the calculation of the capacity credit, which can be assigned to this wind energy conversion system. The approach adopted in this model is to evaluate the Capacity Credit of a wind energy conversion system by evaluating its positive impact on a chosen reliability index, which is Loss of Load Expectation. The Capacity Outage Probability Table is used to evaluate the loss of load expectation without the Wind Energy Conversion System and then re-evaluated again after adding the wind energy conversion system. The observed improvement (decrease) in loss of load expectation is used to evaluate the effective (equivalent) conventional capacity of the wind energy conversion system, which represents the Capacity Credit. The effective conventional capacity of wind energy conversion system is defined as; the capacity of reference conventional generator that has an equivalent impact on the reliability of the power system as the wind energy conversion system has.
The developed model is used to find out the capacity credit of the wind energy conversion system integrated to the Egyptian power system for year 2013. The power system in Egypt has been simulated by its peer groups, which include units of the same technology and within certain capacity range. This reduced the needed computation capacity to a reasonable limit, which can be handled by the available computational capacity. A sensitivity analysis is carried out to find the impact of different input parameters on the resulted capacity credit assigned to the wind energy conversion system. These include the penetration level of wind energy conversion system integrated to the system, the reliability of the reference generator, the base case reliability which stands for the reliability of the power system excluding the wind generation, the characteristics of the power curve of the wind turbine and the number of the representative turbines.
The study also includes the quantity of the conventional capacity, which can be avoid, if an integrated wind energy conversion system of 4000 MW is integrated to the system and their avoided investment.
It has been found that, the capacity credit reduces as the penetration level of wind energy conversion system increases. Also for low wind energy conversion system penetration, compared with the total capacity of a power system, the Capacity Credit is very close to the Capacity Factor. At higher penetration level of wind energy conversion system, the Capacity Credit’s value depends on the base case reliability of the power system. The higher the base case reliability, the less loss of load expectation and the less Capacity Credit’s value can be obtained.
As for modeling purpose the representative turbine concept is used, since it is almost impossible computationally to represent all the real physical number of wind turbines. It has been found that, the Capacity Credit increases with the increase in the number of representative wind turbines. This general conclusion is based on the assumption that all the representative wind turbines are statistically independent, which may not be the case in case if the same wind scheme is considered in the simulation, or most of the wind farms are in the same site, as it was the case in Egypt, in 2013. Also this conclusion does not take into consideration weak effect for the wind farm.
A case study of penetration level of 13.2% (this is equivalent to 4000 MW compared to the total generation installed capacity in the Egyptian power system as per 2013), it has been found that, the capacity credit of the wind energy conversion system at this penetration level is 30.9 %. This is equivalent to 1238 MW of conventional generating capacity with 95% availability factor. Taking this capacity credit into consideration, 2341 MW of conventional generating capacity can be avoided, considering 1% loss of load expectation as a planned target.
This study is important for the power system planners in Egypt, as the share of renewable energy in the power mix is expecting to increase to 35% by 2035, according to the sustainable energy strategy for Egypt 2035.