Power regulation resources required by wind power in Finland and regulation characteristics of power plants

This paper presents different technical possibilities to balance the short term production and consumption of electricity in Finland. Based on several wind measurements in Finland, the amount of wind power variation was calculated for a scenario with 2000 MW wind power in Finland. Additionally, an estimate of the reserves needed for wind power and an analysis of the regulating power market (balancing market) in Finland was made. Hydro power and gas turbines can be regulated by at least 40% of the maximum capacity in one minute. Condensing power plants fuelled by coal (or peat) can be regulated by 5% (or 3%) of their capacity in one minute. The power regulation characteristics in combined heat and power plants (CHP) vary from one plant to another. Therefore no general figures can be given. However, CHP can have possibility for high regulation capacity if heat storage are provided. The one minute power regulation for pressurized water nuclear reactors can be from 1 to 3% of the capacity. Based on these figures and on the installed finnish electricity production capacity, there is 2100-2200 MW (hydro power and gas turbines) of power reserve capacity in Finland. The maximum power variation in wind power production from hour to hour has been 16% and the corresponding standard deviation is 2.7% of the installed capacity, from three years of measured power production data in Finland. Based on these measurements a scenario with 2000 MW wind power in Finland was made. In this scenario the maximum hourly production variation would be 20% and the standard deviation 3.4%. This study also examines the changes in Finland's regulating power market in aggregated regulation bids, volume of regulating power and regulating power price. Both regulation bids and volume of regulating power vary in time. In recent years there have been an increased number of peaks in the regulating power price. If the wind power capacity (2000 MW) would be geographically distributed, it would unlikely have an impact on the amount of the disturbance reserves. The influence on the needs of the frequency controlled normal operation reserve can not be specified with the current (hourly) wind power measurements in Finland. Also sufficient slow reserve capacity and working order must be ensured when the wind power production increases. Adding wind power to the power system will clearly be seen in the regulating power market. The current capacity available to the Finnish regulating power market can be insufficient at times when changes in the power production increase.