Debunking Data Center Cooling Myths – You Can Cool Better with Less Equipment
Data centers generate an abundance of two things – information and heat – both of which continue to grow exponentially. The over 4.3 billion internet users’ appetite for information, whether it is social media, eCommerce, emails, product/information searches, or company look-ups, has been especially voracious during the pandemic. Even though employees at most companies have been working from home, their data centers have probably been working overtime to meet the increased load of information transfers and communications. As data centers process increased levels of information, servers are required to run more and at higher processing speeds. Consequently, data centers are consuming more energy and generating more heat than ever. Summer weather conditions, and the corresponding increase in heat loads, can also play a significant role in testing how effective data center cooling systems operate.
Server technology is becoming more energy-efficient and powerful in its information delivery capacity. However, despite the technological advances, overall energy use in a data center continues to increase. As companies use more complex software and move more information around to satisfy the base of worldwide internet subscribers, data center applications will continue to grow. The more information that is available, the more time users will spend on the internet. Currently, internet users already exceed 6 hours online every day.
How does increased internet use impact a company’s energy costs? Increased information processing leads to higher server energy consumption. As servers use electricity, they generate heat in equal proportion (1 kW of electricity used generates 1 kW of heat which must be removed). The increased passage of electric current through a server causes more heat to be expelled. For reference, a basic server running email or website applications can easily consume 1 kW of power, and expel 1 kW of heat. How much heat is that? Put your hand over your toaster while it is operating to feel a comparable level of heat. Servers such as blade servers or high-performance servers can generate over three times that amount of heat!
How You Can Simultaneously Reduce Operating Cooling Costs and Increase Cooling Efficiency
Data centers are generally closed environments filled with servers that generate a significant amount of heat. This heat must be reduced to an acceptable thermal level prior to being returned to the servers. As server densities increase and the number of servers in a rack increase, more electricity is consumed and more cooling is required.
A common misconception is that the IT equipment represents the vast majority of power consumption in a data center. In many data centers, the power consumption for IT and cooling equipment is equal, and it is not unusual to encounter cases where cooling power consumption exceeds that of the IT equipment. Worse yet, most data centers are operating with much more cooling capacity than required due to poor airflow conditions in the data center. Why is this a bad operating practice? First, large cooling systems are high energy users which in turn means higher operating expense for a company. Secondly, the more a cooling unit operates, the higher the maintenance cost will be – more operating expense. And thirdly, in many cases excess cooling in a data center causes the cooling equipment to operate less efficiently, consuming even more electricity.
The most common rationale supporting the excess cooling capacity approach is that there are “no overheating problems or alarms occurring, so everything must be good.” Given today’s energy costs, the alarm-based rationale amounts to a very expensive and ineffective approach to cooling. Luckily, it is one that can be easily rectified. A simple rule of thumb is that if you need to wear a jacket in your data center, your cooling energy costs are many times higher than they need to be.
Accommodating Increased IT Loads: The Less Expensive Solution
One simple, but expensive, solution to accommodate increasing IT loads and heat generation is to add another cooling system. This is an expensive proposition – we’re talking hundreds of thousands of dollars here! Cooling equipment is (1) expensive, and (2) takes up a lot of space in a data center – this means less space is available for IT equipment. Additionally, considerable planning is required to determine where in a data center the new cooling system should be placed. Next, companies must consider the need for HVAC work to get power and plumbing to the unit. If a new condenser is being placed on the roof, does the roof meet the load–bearing requirements?
The other alternative is to optimize or “rightsize” the existing cooling systems to gain more cooling capacity and deliver the airflow to where it is needed. An increase in cooling effectiveness means the cool air is being delivered to where it is needed, therefore increasing the cooling capacity of existing cooling systems and enabling an increase in IT load to meet growth projections for future years. Optimized cooling systems require less energy to cool the same amount of heat, significantly reducing operating costs. Even better, in data centers with multiple cooling systems, it is possible that one or more can be put in standby mode. Not only does this reduce energy costs, but it also ensures back-up cooling exists in case of the failure of another unit.
Rightsizing means adequate cooling is being provided to ensure ASHRAE thermal compliance in a data center is being met during all seasons of the year while achieving improved energy efficiency. Rightsizing offers benefits beyond just reducing energy costs. By freeing up cooling capacity,
- additional IT load can be added without the large capital expense of a new cooling system;
- cooling equipment operates more energy–efficiently;
- less equipment maintenance is required; and
- if cooling units can be put in standby mode, the life expectancy can be greatly increased.
To help you achieve these goals, a high–level assessment is conducted as a preliminary step. During this process, SCTi collects basic information that is used to evaluate the potential for rightsizing. Under the current pandemic chaos, the high–level assessment can be conducted virtually, and if the results indicate a more thorough investigation is required, a site visit can be scheduled for later in the summer.
Please let us know if you are interested having SCTi help you to reduce cooling energy costs while improving cooling effectiveness by conducting a high-level assessment for your business. Just email us at email@example.com. Also, for more information about how you can implement a cooling optimization project for up to 50% less, check out our new webinar: Handle the Summer Heat: Right-size Data Center Cooling and Earn Energy Incentives.