Data Centers pose a problem when it comes to being energy efficient. Servers are on all day, every day and are expected to perform with a speed and reliability that we rarely expect from any other service. As a result, they generate tremendous amounts of heat and consume tremendous amounts of power. However, there are solutions that have come out within the past few years that make it possible to use less power while still meeting everyone’s expectations.
Windows NT 4.0 had a problem. It was difficult, if not impossible, to run multiple applications on the same server. Since this was the dominant platform for corporations, this lead to a mindset among IT professionals that the more servers you have is proportional to how important you are. When the Enron debacle happened with the rolling blackouts in California, IT Managers began to change their perspective. With the introduction of various virtualization engines such as VMware, Hyper-V, Xen and OpenVZ, it’s now possible run multiple servers on a single computer or even a small computer cluster. This means that Virtual Machines can be dynamically allocated resources as they need it and scaled back when they don’t. VMware is particularly good at this since they will also power down CPUs when they are not needed.
To run a robust virtualization environment, the disk space should be separated from the CPU cluster. Disks use a finite amount of power. By consolidating the disk space to a single cluster, it is possible to only use the amount of disk space that is actually needed rather than the amount of disk space that is desired. Nearly all virtualization engines will dynamically grow VMs to only use the amount of disk space that is needed. There are also SAN systems such as EMC and Copan Systems that will dynamically power down disks as needed to further reduce the overall power consumption.
Many data centers are dedicated buildings. This means that there is an unused piece of real estate that goes to waste: the roof. Since solar panels are getting more efficient year by year, it’s now possible for data centers to get a significant portion of their power from solar panels that are competitive to the costs of getting power from the local utility companies. While it will still take a long time for the efficiency of solar panels to equal the needs of the entire facility, it will still take a significant portion of power off the grid. During the summer months, power companies are typically struggling to keep up with the overall demands of residential and commercial AC systems. As a result, the local utilities are pressuring the data centers to reduce their power consumption. Solar is now a cheap way to do just that.
Geothermal Heat Pumps
Data centers need a tremendous amount of cooling. The more power that is consumed, the more adequate cooling is needed to keep them from overheating. Traditionally, air based cooling towers have been used to cool the rooms. Now there is a newer technology that is gaining traction: Geothermal heat pumps.
Geothermal heat pumps are a technology that uses the temperature of the ground to heat and cool spaces above ground. The Tennessee Valley Authority has already done a large study on this technology and has shown significant savings in not only power consumption, but overall costs as well. Traditional chilling towers require a lot of maintenance, are prone to failure, and require a routine chemical treatment to prevent corrosion and freezing during the winter months. Geothermal heat pumps require fewer moving parts and produce consistent results regardless of the time of year. Furthermore, geothermal heat transfers are more efficient than air cooling resulting in lower energy costs.
Data centers certainly have distinct disadvantages when it comes to being green. With proper planning, those problems are not insurmountable. For large enterprises who maintain their own facility, it will provide savings well into the future. For the small and medium sized businesses, consider hosting your applications and services with a company that uses these techniques to reduce their consumption. Not only will it make your operation a little more green, but less prone to failure as well.