  Reconfigurable intelligent surfaces (RISs) are anticipated to transform
wireless communication in a way that is both economical and energy efficient.
Revealing the practical power consumption characteristics of RISs can provide
an essential toolkit for the optimal design of RIS-assisted wireless
communication systems and energy efficiency performance evaluation. Based on
our previous work that modeled the dynamic power consumption of RISs, we
henceforth concentrate more on static power consumption. We first divide the
RIS hardware into three basic parts: the FPGA control board, the drive
circuits, and the RIS unit cells. The first two parts are mainly to be
investigated and the last part has been modeled as the dynamic power
consumption in the previous work. In this work, the power consumption of the
FPGA control board is regarded as a constant value, however, that of the drive
circuit is a variant that is affected by the number of control signals and its
self-power consumption characteristics. Therefore, we model the power
consumption of the drive circuits of various kinds of RISs, i.e., PIN
diode-/Varactor diode-/RF switch-based RIS. Finally, the measurement results
and typical value of static power consumption are illustrated and discussed.
