How HTDC Uses Hot Aisle Containment for Energy-efficient Cooling


The search for energy efficiency is a constant in every industry. Data centers make no exception. 

“The brains of the internet,” as data centers are often called, were expected to be massive energy consumers, especially with computing power growing exponentially year after year. However, technology brought us a nice surprise: even though the amount of computing handled by data centers has more than quintupled between 2010 and 2018, the energy used has increased by a mere 6%. 

Today, data centers use about 1% of the energy consumed globally. All of this is thanks to the developments in technology and to a relatively recent, but very important shift. The traditional and inefficient data centers operated by banks, retailers, or major companies in other industries have been replaced by the more energy-efficient ones operated by data storage professionals.

A lower-than-expected energy consumption for data centers doesn’t mean that we can’t do even better. As data center usage increases, energy consumption and CO2 will also increase, so it’s up to us to keep everything under control. This is why it’s imperative to find and implement energy-efficient solutions for data centers as early on as possible.

data center energy usage
Infographic from Nature

At HDTC, we take our energy consumption and CO2 emissions very seriously. This is why our Iowa-based data center uses hot aisle containment as a temperature control method. Find out what hot aisle containment is, why it’s necessary, and how this benefits you as an HDTC customer.

What Is Hot Aisle Containment?

Hot aisle containment is a cooling technique that encloses warm exhaust air in the data center and sends it back to the cooling equipment. This way, the hot air is reused instead of being sent back into the atmosphere.

htdc hot aisle containment

The rationale behind air containment is pretty simple: isolating the cold and the hot air in the data center allows for maximum cooling efficiency. 

Cold air containment follows the same principle, but this technique is used to regulate the air that will be injected at the front of the hardware. With the aisle where cold air is supplied enclosed, the rest of the data center can become a hot air return space.

While aisle containment has undeniable benefits (see below), the data centers that plan to use this technique have to be projected to allow for it from the get-go. You can still use aisle containment in a data center that wasn’t initially projected for it, but it is more cumbersome, more expensive, and less effective. This is why most modern data centers are designed for hot or cold aisle containment.

You can spot what your data center is using right away. If you walk down the hot aisle, you should see the rear of the servers.

Curious to see how hot air containment feels like at the HDTC headquarters? Schedule your tour and we’d be happy to walk to you through this process and through all the other energy-efficient measures we have implemented in our data centers. 

Top Benefits of Hot Aisle Containment

Here’s why a data center that uses hot aisle containment is more energy efficient:

  • Hot aisle containment has a 40% improved energy efficiency compared to an uncontained environment.
  • Because hot air is properly returned, the precise distribution of supply air is less of a critical step in data centers.
  • The open areas within the data center are always cool and thus they can be used for storage cabinets or low-density racks. This means that we can do more within the same space, without compromising security or safety.
  • Data center engineers and technicians have a more pleasant working environment since the uncontained area has bearable temperatures. Otherwise, they would have to face extremely high temperatures. On the other hand, when the technicians have to work on a certain piece of equipment, the hot aisle compartment can be very uncomfortable. Luckily, this can be mitigated easily with local cooling.
  • Hot aisle containment allows us to avoid huge expenses like supply ductwork or raised floor distributions. These savings are reflected in the cost savings we pass along to our customers.


While aisle containment is already a mainstream technique that’s widely used, it’s not applied to all data centers. If you want to make sure that the data center where you host your assets is energy efficient and environmentally friendly, we recommend you look for partners that implement aisle containment or have sustainability in mind in operations.

HDTC is committed to offering energy-efficient solutions and to running safe and secure data centers with a minimal carbon footprint. As new environmentally friendly solutions appear, we evaluate them for our data center.

Want to learn more about hot aisle containment? We’d love to chat with you! Give us a call or drop us a line anytime.