Frequency Reserve Service From Heat Pumps and Electrolyzers in Power Systems: A Sealed-Bid Auction Mechanism

With the increasing integration of renewable energy sources (RESs), power system inertia is steadily declining, leading to more pronounced frequency variations during disturbances. Therefore, in future low-inertia grids, frequency reserve service (FRS) from the controllable load sector will become increasingly critical. While much research has focused on FRS from RESs and Active Controllable Loads (ACLs), such as Energy Storage Systems (ESSs) and Electric Vehicles (EVs), the potential of Passive Controllable Loads (PCLs) has been largely overlooked. Additionally, there is a lack of an appropriate framework in the literature to determine the optimal price and quantity of FRS from each supplier. Hence, this paper addresses these gaps by investigating FRS from heat pumps (HPs) and electrolyzers, two key PCLs expected to play crucial roles in future power grids. Furthermore, a sealed-bid auction (SBA) framework is proposed to determine the optimal price as well as quantity of FRS from various suppliers, using nadir point deviation (NPD) and the rate of change of frequency (RoCoF) criteria of the frequency response. According to the results, when the system inertia decreases from 5 seconds to 2 seconds, the required FRS reserve increases from 0.07 p.u. to 0.24 p.u., and the FRS price approximately doubles. Finally, the analyzed case studies show the effectiveness of the HPs and electrolyzers as well as the developed market model to improve the frequency response of the system.