In this paper, we explore the impact of wind generation on isolated power systems, using the system of Cyprus (an island) as a case study. Since 2010, Cyprus has been facing the challenge of integrating intermittent wind generation, while maintaining a secure and economical power system operation. This integration has raised the reserves requirements, and has undermined the ability to accurately track the unit commitment and dispatch day-ahead plan in real time. To evaluate the impact of these effects, we model the daily electrical power system operation of Cyprus as a day-ahead unit commitment and economic dispatch problem, and simulate the system for a long horizon of many days, under different scenarios of wind penetration, using historical data of wind generation.

Photovoltaic (PV) systems generate electricity in the daytime when system demand is generally moderate to high. For Mediterranean countries, there is also seasonal coincidence of high system demand and high PV load factors. The present study quantifies the above statements by calculating the load factor of the PV system when system demand is high (above 90-99% of the maximum demand of the month). The percentage of time the PV load factor is above 90% for these periods of maximum demand is evaluated. The PV load capacity contribution is defined in this study as the minimum PV load factor during these periods of high demand. Actual generation data from a static (without tracking) mono-Si PV system, recorded every half hour for the year 2010 are compared to system demand data. The seasonality analysis indicates that PV contribution to capacity is only significant during the months May-October. For the months November-April, when daily demand peak occurs during the evening, PVs do not contribute towards capacity. The evaluated capacity contribution of PV systems depends on the threshold of maximum demand considered (90%-99%). For the threshold of 95%, the capacity contribution for May-October ranges between 27%-41% of PV installed capacity. Hindawi Publishing Corporation