We tested the peak power consumption of a NAS at the wall during a run of CrystalDiskMark 5.0.2 as this version of the benchmark runs the read and write benchmark suites separately so its easier to monitor what power the device is using during each function.
The 2.4GHz Intel Atom C2538 inside the DS1817+ has a TDP of 15W, so to keep the power demands as low as possible, hard drives need to chosen carefully. The eight WD 6TB drives we used to test the NAS are each rated at 5.3W average when actively reading or writing and have an idle rating of 3.4W.