5/28/2009 1:16 PM
More ways to save on energy
This series on reducing a facility’s power consumption has focused on those areas most easily modified to save on power costs — the HVAC system and lighting — all beginning with an energy audit.
There are, however, other areas an engineer may want to consider. Let’s look at a couple.
Let’s begin our examination with hard disk drives. What used to be kilowatt-consuming devices, today’s individual HDD draw relatively little power. However, as video files get larger, the need for ever-increasing storage is obvious. Fortunately, drives are smaller and faster than ever. And, that trend will continue.
What can’t continue is the ever-increasing demand for power. Stations used to have perhaps 10 disk drives. Now 100 and more are common. Let’s compute the cost to continually spin the drives on just three video servers.
Let’s assume the facility operates three video servers, each with 16 hard drives. Each server holds 250GB and consumes 1.05kW. Because this is a broadcast system, we’ll need at least 500GB for the play-to-air system, therefore two servers and a 250GB off-site backup video server.
Operating 24/365 = 8760hr/yr
Yearly load = 8760hr/yr * three servers * 1.05kW/server= 27594kWh
Yearly power cost = $0.10/kWh * 27594kWh = $2759.40
Can this cost be reduced?
First, many video servers have special management functions that permit spin downs during periods when the operator believes the drive won’t be immediately needed. Using such features may be especially effective in news, editing and archive applications. Engineers can preset the drives to spin down after a predetermined period — or even at predetermined times, like overnight. Also, parts of the server can be spun down if the drives aren’t needed.
What about the backup system? Do the HDDs in that off-site system need to continually operate?
Suppose it took three hours to transfer one day’s worth of backup files. At the end of that period, the backup server drives would spin down until either they were needed for emergency play-to-air or it was again time to download the next day’s backup files. What savings might be possible?
Instead of operating 8760hr/yr, these drives operate only:
3*365hr/hr = 1095/hr
Yearly cost = $109.50 for backup server only
Yearly load for three-server system = 8760HR*2.10kW + $109.50 = $1949.10
Yearly savings = $810.30
If your backup mirroring takes place at midnight for the next day(s), why spin those drives after the backup is complete? Working closely with the hardware provider, it is possible to easily implement new powering options that permit the drives to spin down in times of nonusage. These are the kinds of choices each user can make. There is no one right answer.
Dump the old
Another way to save on power is by eliminating old systems. If you’re keeping old equipment powered — just in case it might be needed — forget it. Move any content that resides on that format to a new format. Then, get rid of the old tape machine or server.
If you are afraid that turning off the device may kill it, then you’ve already made the wrong decision. Keeping an old server or tape machine around just because it makes you feel more secure is bad engineering and bad business. The practice is neither efficient or reliable. And, unless you’re continually testing and using the server, it is likely to fail anyway, just when you do want it most. Recycling it is the best solution for lots of reasons.
So, what’s the bottom-line on saving money on electricity? Outside of generating your own power via a water-powered generator, the next best step is to use as little power as possible.
• Begin by conducting an energy audit
• Reduce business lighting by replacing incandescent lamps with CFLs, halogen and LED lamps.
• Use automation to turn lights and other systems off when they are not needed.
• Update HVAC and environmental systems with more efficient ones.
• Ask about power consumption when you buy equipment.
• Dispose of old equipment.
• If a system isn’t needed 24/7, turn it off.
In today’s fast-paced and increasingly cost-sensitive production environments, sometimes saving money is the best way to make money. Move your engineering department from the minus side of the ledger sheet to the plus side. Show management where to find those hidden cost savings.