Well, depending on the hard drives. In operation 22-25 watts, standby 10 watts, start-up from standby briefly 38 watts measured at 230V

My NAS is connected to a Tapo socket according to their software I have one. Daily consumption between 0.250 to 0.290 kWh per day. With 2 hdds without M2 SSD

This question can hardly be answered correctly as the consumption (also) depends on the general load and the hard drives used.