Voltage drop (IR drop) and Electromigration (EM) reliability are two key related aspects for on-chip power grid design considerations. Good EM reliability ensures no EM induced void formation in the interconnect to cause a fatal resistance increase during product lifetime. It is important to understand the difference of EM characteristics between a power grid and traditional single link EM structures. In this paper, we report the experimental results of EM characteristics of power grid like structures, to demonstrate the power grid design environment, and physical and statistical redundancy benefits for EM reliability. These results can serve as fundamental references for power grid EM limit determination.