What’s the sweet spot? Dell’s take on data center temperatures

Customers frequently ask, “What is the best temperature to run my servers?” With Dell’s recent announcement about servers for “fresh air” or chiller-less environments, the question has gained new significance. We know that not every customer or data center is going to run right out and create a chiller-less facility. With that in mind, our thermal and cooling experts have done extensive lab research to help the rest of us understand where the true “sweet spot” is when it comes to data center temperatures. The truth is, it is much higher than most people would imagine.

Because of the fan power increases that occur when you raise the temperature in your data center, there is a point at which the savings and the consumption begin to negate each other. Based on that information, Dell set out to find that exact point, and discovered that there is, in fact, a verifiable “sweet spot” for operating temperatures.

When using compressor-based means to cool a data center, the highest operating temperature may not be the most efficient, especially if savings at the utility bill level is your goal. Depending upon the IT equipment, the ideal operating temperature is somewhere in the upper 70s or lower 80s. If you have an economizer, you can leverage it to ride the temperature up higher. You are really only limited by your least tolerant IT equipment.

If you decide to use “Mother Nature” to cool your data center, the sweet spot discussion won’t impact you. If 81°F operation results in free cooling around 90 percent of the time, you might avoid the capital costs of compressor-based cooling altogether by extending to capture the remaining 10 percent. Recently, we’ve seen a handful of technology innovators grabbing that last 10 percent by leveraging container deployments, or with other creative models based on IT equipment designed to 95°F. The vast majority of these are in very moderate northern climates, such as Facebook’s recent data center build in Oregon.

With Dell’s IT equipment better suited for higher ambient temperatures, the potential has been opened up for mainstream operations, those in less accommodating regions, and even those who consider themselves fairly intolerant to risk.

We anticipate four scenarios when it comes to economizers:

  1. You’re going to fully embrace a chiller-less strategy.
  2. You aren’t able to go completely chiller-less, so you include a small amount of chilling capability.
  3. You’re a typical economizer user that operates conservatively, could enjoy free cooling for a majority of the year, and would consider experimenting more with increased temperatures.
  4. You’ve got a traditional data center and hopefully won’t face a mandate for economizers, but you can still greatly improve energy use if you operate at the sweet spot.

All of these scenarios have their pros and cons and will greatly depend on your unique business needs. But, regardless of your circumstances, higher temperature tolerant IT equipment will help you move toward a more efficient operation scenario. Having a strong partner who can assess your current situation and work with you to determine which strategy makes the most sense for you will become increasingly important.

Are you considering making changes to your facility to take advantage of free air cooling? What are some of the innovative things your business is doing to minimize energy consumption of your IT equipment? We’d love to hear your thoughts. Leave us a comment!

Check out Dell’s whitepaper Data Center Operating Temperature: The Sweet Spot for all of the in-depth technical details and graphs galore.

About the Author: Milly Pellizzari