While typical energy audits focus on the mechanical and electrical infrastructure, in data centers the facility framework is only one factor in the cost equation. Often times improving in other areas can be even more rewarding. For example, consideration of the actual kilowatts consumed by servers and other IT hardware is crucial when examining energy efficiency in a data center.
Data processing equipment accounts for most of the energy consumption in a data center, and because of this, facility executives really need to start by thinking ‘inside the box’. Best practices in the type, usage, and configuration of deployment all can significantly reduce the overall energy needs for this equipment.
Pull the Plug on Idle Servers
It’s a simple concept really, if it’s not doing anything, unplug it. However, in many data centers, up to 15% of the servers should be decommissioned and yet are left running for no other reason than lack of drive to clean up outdated equipment. Some estimates indicate that the cost of each idle server can exceed $1,000 annually when considering total data center energy usage. That’s a lot of wasted capital! Addressing the issue can have an immediate impact on the bottom line.
The solution is to establish a rigorous program to decommission obsolete hardware.
Maintaining an asset management database is a necessity to help enterprises ensure that they are consuming resources efficiently. This database should contain accurate, up-to-date information on server location and configuration, enabling IT staff to easily identify variables of power, cooling, and available rack space when planning future server and storage deployments and identifying potential systems to retire.
Upgrade to Energy Efficient Servers
Another simple measure to reducing energy consumption is to buy more energy-efficient servers. The bulk of IT departments ignore energy efficiency ratings when selecting new hardware, focusing on performance and up-front costs rather than total cost of ownership. However, if just one server uses 50 watts less than another it will equate to a savings of more than $250 over a three year period, and an even more profound savings of $1,500+ on facility infrastructure expenditures can be realized.
Data processing equipment all rely on power supplies to take incoming power to the device and distribute it accordingly throughout its internal components as required. These power supplies are typically specified by the manufacturer to provide for the worse case conditions of the device under a maximized configuration. In the past, these power supplies typically were rated far beyond the components capabilities to provide a “safety factor” in the device. As more pressure is being brought to the forefront on energy efficiency in computing, manufacturers have been striving to match their power supplies more closely to the components capabilities, or power parity.
One of the more power consuming components in most IT processing equipment are the fans required to provide air for proper cooling internally within the equipment. These fans run continuously as long as the device is running. Both equipment and chip manufacturers have been making strides to better pair fan use with actual equipment needs. As chip development continues, heat tolerance is being increased. Also, fans are being created which can be run in stages depending on the processing load of the equipment. This means that fans can run at lower speeds when processing is at a lower state, thus consuming less power.
Processing equipment developed within the last 3-5 years (depending on the manufacturer) is likely to be relatively energy efficient, anything older than that certainly should be evaluated.
Consolidate and Virtualize
Another “low-hanging fruit” in many data centers is server consolidation and virtualization. Typical utilization rates for non-virtualized servers is measured between 5 and 10 percent of their total physical capacity, wasting hardware, space, and electricity. By moving to virtualized servers, data centers will be fully supported with less hardware, resulting in lower equipment costs, lower electrical consumption (thanks to reduced server power and cooling), and less physical space required to house the server farm.
It is important to remember that not all applications and servers are good candidates for virtualization which adds complexity to the endeavor.
Along with consolidated server applications, associated storage for these systems is also becoming more consolidated as well. Storage Area Networks (SAN) and Network Attached Storage (NAS) solutions are becoming the norm in data center typologies. Virtualized tape systems are also replacing larger tape storage devices of the past. As these systems become more regularized, they have also been increasing in density. This allows more storage in the same footprint with only marginal increases in energy consumption. The advent of solid state storage devices (SSD’s) will likely only create higher densities with lower overall power consumption in the future. Although these devices are not yet in production on central storage equipment, it will only be a matter of time before they are utilized.
The Bottom Line
A comprehensive efficiency strategy that targets IT processing equipment in addition to other tactics can substantially reduce energy consumption and net large savings. A facility-wide energy audit from an experienced partner will help to identify the areas where the most immediate impact can be achieved.