I wanted to put a little info I had with my CS240's while I was IT Director for Money Mailer in Garden Grove, CA. I was an early adopter of Nimble (December 2010) and retired several storage systems including 2 flavors of EMC, Apple X-Server, and HP. Specifically, I wanted in this post to talk about power consumption.
In late 2012 Southern California Edison had a rebate program that would reduce costs if you could show how you were taking steps to reduce power consumption. I was asked to describe what those steps were in the data center and it was validated by a California sanctioned auditor. I was finally retiring over 40u of EMC storage and 8u of Apple X-Raid storage due to my Nimble arrays absorbing primary storage responsibilities in my datacenter. The auditors asked me to install "meters" on the EMC, Apple, and Nimble gear to show how much I was going to reduce power consumption.
I won't go into how much power the EMC or Apple storage was consuming (okay - it's was over 6KVA) but focus mainly on what my Nimble CS240 array was using. The Nimble CS240 has two power supplies which were plugged into APC 3phase 115V PDU's with standard NEMA 5-15 plugs.
When the array is plugged but off it only consumes about 0.3amps. At startup the Nimble array consumes approx. 5.7amps for about 60 seconds and then idles at around 3.8 to 4.2amps. During a normal workload (see below) the array was consuming about 4.6 to 4.9amps.
35 volumes serving 15 Dell ESX hosts and a full UCS chassis
120 vms (including Exchange 2010 CAS, HUB, and MB, large SQL2005 DB server (single instance w/ 60+ DBs, 5 Linux/Informix DB servers, 2 SharePoint instances, fileservers, and dozens of apps servers
150 vdi workstations (persistent win7 pro @ approx. 25 IOPS/workstation)
Southern California Edison sent me a check for almost $9,000 and my datacenter power consumption dropped from $12K/month to less than $6K. (I was also able to put one of the 10ton Liebert AC units in standby mode since I wasn't generating the same BTU's.)
Let me know if you have any questions or need more details.