Definition of PUE (Power Usage Effectiveness)
PUE (Power Usage Effectiveness) is a key indicator used to measure the energy efficiency of data centers. This global benchmark, introduced in 2007 and explained in standard EN 50600-4-2, assesses the energy efficiency of data centers, comparing the total energy actually consumed by the data center with that used by IT equipment. With the increasing energy requirements of digital infrastructures driven by the rise of AI, understanding and optimizing PUE is critical to reducing the environmental impact and running costs of data centers. Browse this article to find out what PUE is, how it's calculated, and strategies for improving energy efficiency.
What is PUE?
PUE, or Power Usage Effectiveness, is a metric developed by the Green Grid to assess the energy efficiency of data centers. It is the ratio between the total energy consumed by a data center and the energy used specifically by IT equipment. A PUE close to 1 indicates efficient energy use, as it means that most of the energy is consumed by the IT equipment itself, rather than by cooling or other energy needs.
Why is PUE important for data centers?
The IoT and AI revolutionize the demand for computing power and infrastructure availability in data centers, and these developments have inevitably impacted the operation and energy consumption of our data centers. Today, in view of companies' IT dependency, the trend is to select data centers with the highest TIER level. This type of data center requires a more substantial infrastructure, which logically results in a higher PUE. PUE is essential for data centers, as it enables us to measure energy efficiency and identify opportunities for reducing energy consumption. Improving this ratio can lead to significant cost savings and a reduced carbon footprint, an important factor for companies concerned about their environmental impact. Adopting practices to improve PUE has become a strategic objective for many companies seeking to further optimize their data center operations.
Calculating and interpreting PUE
PUE calculation
Standardized by ISO 30134-2-2016, the PUE of a data center is calculated as the ratio between:
• The total power consumed by the data center, including cooling systems, lighting, UPS, etc. ;
• The power consumed by the IT equipment (servers, storage and network equipment).
This leads to the following PUE formula:
PUE (without unit) = IT equipment power consumption (in kW or MW) / Total data center power (in kW or MW)
Interpretation of PUE results
Interpreting PUE results enables you to target possible improvements. PUE values range from 1 to over 2.5, depending on the energy efficiency of the data center. A PUE of 3, for example, means that only a third of energy is used by IT equipment, indicating significant potential for improvement.
On the other hand, the average PUE of UltraEdge's data centers is between 1.5 and 1.9, confirming the sound management of their data centers, with optimization projects in progress to achieve PUEs between 1.2 and 1.3 on new extensions and new buildings currently under construction.
An efficient PUE of 1.5 or less is often considered a good indicator of optimal energy use in today's data centers.
Strategies for improving PUE
PUE informs data center managers of the energy efficiency of their facility by quantifying energy consumption and its final destination.
- Optimize energy consumption
Optimizing energy consumption can be achieved by implementing more efficient technologies and energy management systems. This includes improving cooling systems and using renewable energy to reduce environmental impact. Regular monitoring of electricity consumption using accurate electricity counters is essential to pinpoint areas for improvement.
- Use of efficient cooling technologies
Cooling systems play an extensive role in a data center's energy consumption. In UltraEdge data centers, we adopt efficient cooling technologies, such as cold aisle containment, to significantly reduce energy consumption. These solutions keep servers at optimized temperatures while minimizing energy use.
- Adoption of energy management practices
The adoption of energy management practices at UltraEdge, such as regular monitoring and analysis of consumption data, is key to identifying and implementing subtle improvements that can have a significant impact on PUE. Our data center management teams must be focused on continuous improvement to ensure optimum energy performance.
- Lessons from best practices
Best practices include the emphasis on proactive energy management and the integration of green technologies. Using renewable energy and optimizing IT infrastructures are core lessons for any data center looking to improve its energy efficiency.
At UltraEdge, we take a proactive approach to improving PUE to better enhance our competitiveness and data center sustainability, while ensuring proper regulatory compliance.