Integration of Renewable Generation into the Portuguese Power System: The Impact of Different Hydrological Regimes

Abstract

The Portuguese power system has experienced an increasing  integration  of  renewable  energy  sources  during  the  last yearsand is still making considerable efforts to increase its share  of  renewable  generation.  Wind  power  is  the  renewable  source  of  energy  that  has  experienced  the  highest  increase.  According to the national power system operator predictions, by the  year  2011,  wind  power  will  account  for  27.5%  of  the  Portuguese  installed  capacity  and  for  37.1%  of  the  generated  energy. Such integration of wind power induces particular challenges in balancing  the  power  demand  and  generation,  emerging  as  the  cause  of  some  power  system  instability.  That  potential  to  the  power unbalances occurrence tends to increase during the years of  higher  rainfall,  especially  in  systems  like  the  Portuguese,  with considerable hydro generation. The  main  objective  of  the  present  paper  is  to  understand  the  sensitivity of the Portuguese power system capacity to integrate the  renewable  generation  under  different  hydrological  regimes.  Along the paper, the authors forecast the potential of occurring power unbalances between demand and generation, analyse the contribution  of  the  installed  pumping-hydro  power-plants  to  mitigate  those  power  unbalances  and  quantify  the  needs  of  renewable generation curtailment.