From GPUs to Airflow: How Energy Efficient Aisle Panels Optimize High-Performance Computing

Reduce data center cooling costs by up to 40%

High-performance computing environments (think every GPU you’ve ever heard of) put out a ton of heat. GPUs. Server racks. Processors. Every component generates hot exhaust air that needs to be cooled… somehow.

If that heat can’t escape, or worse, if cold air mixes with hot air exhaust, then it becomes useless energy wasted on your electric bill.

There is good news…

Implementing aisle containment systems provides an effective solution to streamline thermal management practices. Containment panels create physical separation between cold supply air and hot exhaust air.

Narrowing your focus prevents hot and cold air from mixing and causing havoc with cooling efficiency.

In this article, we’ll cover:

• High Cost of Inefficient Airflow
• How Aisle Containment Works
• Hot Aisle vs Cold Aisle Containment
• Pick the Right Solution for You

High Cost of Inefficient Airflow

Did you know that data centers use as much electricity as entire cities?

A recent report from the research service of the U.S. Congress said that on average, 38% to 40% of total electricity use goes to cooling data center facilities.

That’s right. Nearly half of the energy consumed goes to fighting heat.

But without proper containment cooling technology, cold air will always mix with hot air leaving your servers. This ruins cooling efficiency because equipment temperatures become inconsistent. The cooling systems work harder which means…

Higher electricity bills.

By installing energy efficient aisle panels, you can create dedicated hot and cold zones within your data center. There’s no more mixing. Return air temperatures become more consistent which allows you to gain better control of cooling costs.

GPU/CPU-intensive computing is quickly becoming the standard as we continue to adopt AI and machine learning tech into our workspaces. Data centers running these types of applications can’t afford to ignore cooling inefficiencies.

How Aisle Containment Works

The concept behind aisle containment is pretty straightforward.

Data center racks are lined up in alternating rows with “cold aisles” where the fronts of servers face each other and “cold aisles” where the rears of servers face each other.

Containment systems can be applied to either hot or cold aisles using panels, doors, and ceilings to restrict airflow to a specific zone.

Benefits of aisle containment include:

• Lower cooling costs
• Improved temperature consistency
• Longer hardware lifespan
• Overall better PUE ratings

In fact, according to the World Economic Forum, top performing data centers have PUE ratings as low as 1.09 compared to the global average of 1.56. That’s almost 84% less overhead energy usage.

Eliminating hot and cold air mixing is one of the easiest ways to start improving your data center’s Power Usage Effectiveness (PUE).

Hot Aisle vs Cold Aisle Containment

When it comes to aisle containment, there are two different strategies you can choose from.

And each has its own benefits.

Hot Aisle Containment

Hot aisle containment (also known as HAC) is a method of enclosing or separating the hot aisles within a data center.

Hot aisle containment is like putting a range hood above your oven. It captures heat right at the source and directly redirects it to cooling units.

Reasons to choose hot aisle containment:

• Higher return air temps allow cooling units to operate more efficiently
• Hot aisle is contained so the facility remains comfortable for employees
• Hot aisle containment works great with raised floor cooling units
• Provides better thermal efficiency overall

Data from Energy Star shows that hot aisle containment provides 40% better energy savings over cold aisle containment solutions.

Why? Hot aisle free cooling units can operate at higher temperatures which equates to higher efficiency.

Cold Aisle Containment

Cold aisle containment is the opposite of hot aisle containment.

Instead of enclosing the hot aisles where exhaust air is expelled from servers, cold aisle containment targets the cold aisles where supply air is drawn into equipment.

Benefits of cold aisle containment:

• Easier to install in existing facilities
• Less expensive upfront
• Can be applied to uneven rack densities
• Simple set up for small data centers

Hot and cold aisle containment both accomplish the same task of preventing cold supply air from mixing with hot return air.

Pick the Right Solution For You

Every facility has different requirements when it comes to containment.

Here are some questions you should ask yourself when deciding between hot or cold aisle containment.

• What does the current rack layout look like? Are they evenly spaced?
• Is your data center equipped with raised floor cooling units?
• What is your budget for retrofitting containment?
• Do you have plans for expansion in the future?

If you’re building a data center from scratch, hot aisle containment is typically the best route to take.

Since the infrastructure can be designed around thermal efficiency from the start.

For existing facilities, cold aisle containment makes more sense.

It’s easier and faster to retrofit into the current setup.

But don’t forget about material quality.

Aisle containment panels are constantly being exposed to extreme temperature changes, humidity variations, and physical contact.

Cheap materials won’t last long in a harsh data center environment. Choose durable plastic panels and curtain systems designed to maximize longevity.

Blanking panels are another important factor in containment. These panels slide into unused rack spaces to prevent hot air from traveling forward and cooling equipment from the rear.

Maintaining Your Containment System

Once containment is installed, there are steps you can take to maintain optimal performance.

• Monitor panel connections and seals to ensure there are no gaps
• Watch for temperature variances across hot and cold aisles
• Adjust CRAC/CRAH units to account for new airflow patterns

CRAC/CRAH units will likely require some tweaking after containment is applied.

Since hot and cold air are no longer mixing, return air temperatures will change. Set points should now be based on server inlet temperatures instead of return air temperatures.

Payback on containment can vary but most facilities see a return on their investment between 6-18 months. After that, all that energy savings is straight profit.

Wrapping Up

There you have it.

Aisle containment systems are a great way to begin optimizing your high performance computing solutions.

Not only do they provide physical separation of hot and cold air, but they can also help you gain valuable control over cooling efficiency and energy usage.

Here’s what you need to remember:

• Containing hot and cold air streams can reduce data center cooling costs by up to 40%
• Hot aisle containment creates better thermal efficiency
• Cold aisle containment is more cost effective for retrofitting purposes
• Energy efficient aisle panels are durable and long lasting

If your data center is running GPU/CPU intensive workloads, proper airflow management should be a top priority. Incorporating containment prevents losing expensive energy on inefficient cooling practices.