You can apply the required control signals on the memory to address it , wright and read it with a given data and then all what do you need is to add a current probe at the output wire from the power supply of the circuit say this current will be iDD(t).
Then you can easily calculate the power dissipated by Pavg=( integral iDD(t) VDD dt )/ T obs where T is the measuring time which must be made multiple wright read cycles. The simulator measures also the dissipated power Pavg of the circuit directly.