sentences:  Secondly, wind is a highly unpredictable factor and the schedules for wind installations are often far off, despite major efforts to statistically predict the short-term wind conditions.The two above mentioned factors combined introduce a new source of volatility into an already volatile system that gives rise to electricity prices.While the measures aiming at increasing the electricity production of renewable energy sources can be considered highly effective and successful, they lead to price distortions and exerted increased pressure on the markets, as well as on the electricity grid.