Duck curve problem solving strategies with thermal unit commitment by introducing pumped storage hydroelectricity renewable energy

摘要

In recent years, the price of photovoltaic (PV) has been decreasing dramatically, that has been increasing the installation of PVs in smart grid and roof photovoltaic (PVr). There is no doubt, this is a positive development of smart grid for the world. As we know every good thing has a bad side too, PVs definitely generate power in the day time, so huge number of PV's power penetration in the daytime changes the load demand of fossils fuel based thermal generations and load curve becomes duck shape. In duck curve, peak and off-peak gap is very large. It is a challenge to cut the peak and increase the off-peak load which means load leveling is very important. If peak and off-peak gap are more so start-up cost (SUC) of thermal generators will be more. Besides, more thermal units have to be run to fulfill the peak load. Therefore, it is very important to run thermal units optimally. As we already knew, duck curve has very high peak so the only optimization is not enough to bring good results. Therefore, energy storage system plays a vital role to level peak and off-peak load. However, battery energy system (BESS), still installation cost is very high specially NaS battery. That is why in this research considers concentrated solar power (CSP) and pumped storage hydroelectricity (PSH) as the energy storage system (ESS). In this research, optimal unit commitment (UC) of thermal generators and PSH is introduced for saving the fuel cost and SUC of thermal generators. Optimal results of the proposed research model are determined by using MATLAB^®INTLINPROG optimization toolbox.