You can ensure better efficiency in your datacenter by looking at some common sources of problems:
- Power distribution units operating well below their full load capacities
- Air conditioners forced to consume extra power to drive air at high pressures over long distances
- N+1 or 2N redundant designs, which result in underutilization of components
- Oversized UPSs to avoid operating near capacity limits
- Decreased efficiency of UPS equipment when run at low loads
- Under-floor blockages adding to inefficiency by forcing cooling devices to work harder
As we discussed in Chapter 4, the way you lay out your datacenter has a huge impact on the efficiency of the air conditioning system. If airflow is blocked, it is not as efficient. If a hot-aisle/cool-aisle layout is not adhered to, you lose efficiency. When you design your floor layout, you want to do it with hot air and cold air segregation in mind.
Also, be mindful of where cooling systems overlap in your datacenter. This is the ideal location for equipment that runs especially hot or is especially important.
It's not enough just to get the servers up and running; be sure that you enable any power-saving features on the servers. A lot of times IT managers don't set power-saving modes, rather opting for high availability. Setting power-saving modes will help save money by reducing power consumption and cooling costs.
Floor Vent Tiles
Vented floor tiles don't just look cool, they're designed to facilitate airflow. In many datacenters, however, vented tiles are either incorrectly placed or an insufficient or excessive number of vented tiles are installed.
If you use Computational Fluid Dynamics (CFD)—an analysis of airflow patterns—in your datacenter, you can optimize datacenter cool-airflow. This allows you to fine-tune the center's cooling by placing vented floor tiles in their optimal locations. Some vendors will even help you with CFD. By simply fine-tuning tile locations, some datacenters have achieved a 25 percent reduction in cooling costs.
Datacenter design and redesign involves a lot of components. For instance, a seemingly small task such as the placement of vented floor tiles can lead to big savings. However, the biggest thing you can do to optimize your datacenter is to design with rightsizing in mind. That simply means building for what you need.
Rightsizing has the most impact on your datacenter's power consumption. Fixed losses in your power and cooling systems are present whether or not you have a datacenter in place. Organizations that have light IT loads might not even see an impact by its IT department. However, as the IT load gets larger, organizations will see power and cooling expenses climbing. Rightsizing can be accomplished through server consolidation and virtualization.
When you redesign with rightsizing in mind, you must also be cognizant of the fact you will need additional capacity in the years to come. However, if you spend the time and money you need to predict the datacenter power and cooling load, it will pay for itself in both reduced capital and operational expense.
Datacenter Design and Redesign
Designing data centers for energy efficiency
Upgrade to energy-efficient servers
Benefits of using server consolidation for energy efficiency
Printed with permission from The McGraw-Hill Companies. Copyright 2008. Green IT: Reduce Your Information System's Environmental Impact While Adding to the Bottom Line by Toby J. Velte, Anthony T. Velte and Robert Elsenpeter. For more information about this title and other similar books, please visit http://www.mhprofessional.com.
This was first published in July 2009