Decision Making Made Easier with Data Center Sustainability Metrics
Data center and IT infrastructure managers have long been concerned about the performance of their data centers or their infrastructure solutions housed in colocation facilities. Power usage and efficiency are primary systems wherein costs can be controlled. However, they haven’t always been as focused on the sustainability of these solutions.
Today, evidence shows that companies focused on the ESG (Environmental, Social, and Governance) aspects of their business enjoy increased operational efficiency and increased returns. With corporate strategy turned in greater measure toward sustainability and the rapid rise of compute, data center companies must be forward-thinking in their approach to building and maintaining efficient and resilient facilities which will be operable under increasingly strict ESG standards and stakeholder demands.
Fortunately, there are metrics and tools that are readily available for data center managers to make decisions about IT infrastructure solutions when tracking carbon impact to transparently present sustainability and efficiency metrics to company leadership. It is an exciting era in the data center industry where investors, tenants, and facility owners & operators are benefitting from acting as partners in their approaches to ESG. Opening the conversation is driving stronger sustainable solutions for data centers.
Measuring Data Center Efficiency With PUE
One common metric used to measure data center efficiency is PUE or Power Usage Effectiveness. PUE is the ratio of total facility energy usage to the energy consumed by IT equipment onsite. In other words, to have a good PUE is to minimize energy consumption by anything other than IT equipment, such as lighting and mechanical equipment. The perfect PUE is 1.0. PUE may not be the ideal metric to measure the efficiency of a data center, because the fuller the data hall is, the more efficient a building will be. Nonetheless, it is a standardized metric that is widely understood, accepted, and financially beneficial to follow. A global survey of IT and data center managers conducted by Uptime Institute in 2020 showed the average annual PUE of large data centers has improved from 2.5 to 1.59 since 2007.
Expanding Sustainability Metrics For Data Centers Beyond PUE
While data center managers should track PUE and ask for a facility’s PUE when considering a colocation provider, there are other sustainability metrics managers can take into account. Here are five of these metrics.
Renewable Energy Factor (REF)
According to ISO standards, REF is the renewable energy owned and controlled by a data center provider divided by the total energy consumption of the data center. Like PUE, this is a metric that allows for comparisons of data centers of varying sizes. A REF of 1.0 means that all of a data center’s energy consumed is renewable.
GHG (Greenhouse Gas) Emissions
GHG emissions refer to the emissions that occur from resources used to operate a data center, including fuel combustion from generators, sulfur leakage from medium voltage switchgear, and hydrofluorocarbons (HFCs) from cooling systems. Some data centers might also calculate emissions from the transportation of materials needed to operate the data center. GHG emissions also include CO2 emitted to generate the energy consumed by the data center. Emissions for data centers that use renewable energy will be much lower than those that use non-renewable energy. GHG emissions are measured in metric tons.
Carbon Usage Effectiveness (CUE)
According to the ISO, CUE is the ratio of the data center annual CO2 emissions to IT equipment energy demand. Similar to tracking GHG emissions, this metric includes total CO2 emissions, but these are offset by the total IT load, like PUE. Data centers that run off 100% renewable energy can theoretically have a CUE of 0. CUE was a standard developed by The Green Grid and adopted by the ISO.
Water Usage Effectiveness (WUE)
WUE is the ratio of annual data center water consumption in liters to the total energy consumed by IT equipment onsite in kilowatts. A site’s WUE may only include water used onsite for humidification and cooling while others may include water needed for electricity generation to operate the site. Some data centers may track both. WUE is a standard developed by The Green Grid and adopted by the ISO.
LEED-Certified Data Centers
While LEED-certified is not a metric, a new data center that is LEED-certified is a good indicator that the builder has invested in sustainability. To become LEED-certified, companies have to take multiple environmental and sustainability factors into account, including reducing water runoff, reducing water consumption, optimizing energy performance, sustainably sourced building materials, and investment in renewable energy.
Tracking Sustainability with Data Center Infrastructure Management Tools
Data center and infrastructure managers may wonder how they can track and present all of these metrics to leadership. Many modern data center infrastructure management (DCIM) tools provide a way for data center managers to transparently monitor and present energy and water usage, efficiency, and sustainability metrics to leadership. These metrics can help IT management better understand their energy usage and work toward sustainability goals. Many colocation providers utilize DCIM software to optimize their operations.
Companies that are evaluating colocation providers should ask colocation companies for sustainability metrics and how they track them to better align with their ESG goals and to discover differentiators that can translate into both savings and greater efficiency over the life of their deployment.
