This guide of gbc engineers provides a comprehensive overview of best practices for energy efficiency in data center design.
The Urgency of Energy Efficiency in Data Centers
Data centers are the digital backbone of our modern world, powering everything from cloud computing to artificial intelligence. However, they are also among the most energy-intensive facilities, with some consuming up to 100 times more electricity than standard office buildings. This immense energy demand not only escalates operational costs but also contributes significantly to global carbon emissions.
As the digital economy expands, optimizing energy efficiency in data centers becomes imperative. This guide delves into comprehensive best practices for designing and operating energy-efficient data centers, focusing on key areas such as IT systems, environmental conditions, air management, cooling systems, electrical systems, and sustainability metrics.
1. Information Technology Systems
Hardware Location and Consolidation
Efficient hardware placement plays a key role in reducing energy use. In data centers, it’s important to group equipment with similar heat load densities and temperature requirements together. By isolating equipment according to their specific environmental needs, ventilation networks can be optimized for the least energy-intensive settings. For example, setting ventilation networks to the right temperature and humidity levels based on each equipment's requirements will ensure maximum efficiency.
This practice can also be applied on a larger scale across data centers. By consolidating underutilized data center spaces into a more centralized location, you reduce the need for distributed ventilation efforts, thus maximizing energy efficiency. This approach ensures that energy-saving measures are easier to implement and manage. By optimizing the access to hardware, you can also streamline recovery processes and reduce the complexity of maintaining efficient services across a facility.
In terms of content and view management, centralized data allows for better handling of environmental factors and reduces the overhead associated with managing dispersed infrastructure. Consolidation allows for more efficient ventilation, easier search and retrieval of assets, and more simplified disaster recovery processes, as all infrastructure is in a single location with dedicated access control.
Read More: Top 5 Data Center Technologies in 2025: Emerging & Networking - gbc engineers
Virtualization
Virtualization is one of the most effective ways to reduce energy consumption in IT systems. It involves running multiple independent virtual operating systems on a single physical computer, increasing the utilization of the server. This allows businesses to reduce the number of servers required to handle processing tasks. Instead of running many servers at low CPU utilization, virtualization consolidates workloads onto fewer servers that operate at higher efficiency levels.
The result? Virtualization significantly reduces the amount of power needed to run servers, and consequently, the energy required for cooling equipment. It also improves privacy by offering more secure, isolated environments within the same physical machine. Data center managers can also better control access to these virtualized environments, ensuring that resources are allocated based on demand and available capacity.
2. Environmental Conditions
ASHRAE Thermal Guidelines
The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) provides standardized operating environments for data centers. The 2021 ASHRAE guidelines recommend maintaining inlet air temperatures between 18°C and 27°C for most data centers (Classes A1 to A4). Adhering to these guidelines allows for greater flexibility in facility operations and contributes to reducing overall energy consumption.
Recommended vs. Allowable Envelopes
It's crucial to distinguish between the recommended and allowable environmental envelopes. The recommended range ensures optimal energy efficiency and equipment reliability, while the allowable range defines the boundaries within which equipment can function without immediate failure. Designing and operating within the recommended range is advisable for long-term efficiency and reliability.
3. Air Management
Minimize Mixing of Cool and Hot Air
A key objective in air management is to prevent the mixing of the cold air supplied to IT equipment and the hot air rejected from the equipment. By avoiding this mixing, you ensure that the cooling air directly reaches the equipment, preventing bypass and recirculation. Proper air management allows you to increase the supply air temperature while maintaining a "comfort" level for the IT equipment, thus optimizing the cooling system’s efficiency.
To achieve this, you need to design the system in a way that prevents hot exhaust air from circulating back into the equipment's air intake. Using strategies like zoning and air containment systems can further reduce this issue.
Hot Aisle/Cold Aisle Configuration
The hot aisle/cold aisle configuration is a proven method to optimize air distribution in data centers. In this layout, cold air is supplied to the front of the racks (cold aisles), while hot air is exhausted from the rear of the racks (hot aisles). This setup allows cooling systems to focus on maintaining an even temperature in the cold aisles, preventing hot air from mixing with cold air.
Using an overhead or under-floor air distribution system is critical in this design. When using an overhead air distribution system, diffusers should be located above the cold aisle directly in front of racks, instead of traditional office diffusers. This helps prevent air mixing and ensures the effective supply of cooling air to the IT equipment.
For under-floor air systems, it’s essential to ensure that pathways for airflow are not blocked by wiring trays or conduits. Over time, adjustments to the floor tiles or the addition/removal of tiles should be done carefully to prevent disrupting airflow and causing localized hot spots.
Efficient Air Delivery
Overhead infrastructure tends to offer better control over temperature stratification in cold aisles compared to under-floor infrastructure. By using variable air volume (VAV) infrastructure, the air volume supplied to the room can be adjusted based on the temperature control demand, optimizing the infrastructure's operation. Variable speed fans help reduce energy consumption by adapting the fan speed to the current temperature control requirements.
In the case of rooftop units, positioning them centrally over the served area reduces the need for extensive ductwork, cutting costs and improving efficiency. Overhead delivery infrastructure, in general, reduces issues with air stratification and provides better overall performance.
Considerations for Under-Floor Air Supply
Under-floor air infrastructures have their own set of challenges. The under-floor plenum, which serves both as a duct and a wiring chase, can be obstructed by electrical or data conduits, affecting airflow. It's critical to coordinate airflow pathways during both design and operational phases to prevent issues like high air velocity in the plenum, which can cause localized negative static pressure and draw room air back into the system.
Ensuring that the under-floor plenum is deep enough and carefully designing the layout of CRAC/CRAH units can help maintain a more uniform air static pressure throughout the system. Proper planning can prevent areas of the data center from receiving insufficient cooling air, ensuring that the entire room benefits from balanced airflow.
Read More: Top 5 Strategies for Modern Data Center Design in 2025 - gbc engineers
4. Cooling Systems
Packaged DX Air Conditioners
Direct expansion (DX) air conditioners are common in smaller data centers. Energy efficiency can be enhanced by selecting units with variable-speed compressors and incorporating evaporative cooling techniques, which improve heat rejection efficiency. Air-side economizers can also be utilized to leverage cooler outside air for free cooling, reducing reliance on mechanical refrigeration.
Source: What is DX Cooling | Direct Expansion Cooling
Centralized Air Handling Systems
For larger facilities, centralized air handling systems offer several advantages over distributed cooling units. They provide better airflow control, are more efficient at part-load conditions, and simplify the integration of economizers. Centralized systems also reduce maintenance complexity and can improve overall energy efficiency.
Free Cooling and Economizers
Implementing free cooling strategies, such as air-side and water-side economizers, allows data centers to utilize external environmental conditions to cool IT equipment, significantly reducing energy consumption. These systems are particularly effective in climates with cooler temperatures and can be integrated into both DX and chilled water-cooling systems.
5. Electrical Systems
Optimizing the electrical infrastructure is essential for energy-efficient data center design. Selecting high-efficiency uninterruptible power supplies (UPS) and power distribution units (PDUs) can reduce energy losses. For instance, using dry-type transformers with a 176°F temperature rise can consume 13% to 21% less energy compared to those with a 302°F rise. This ensures that data center operations are running more efficiently, while reducing energy consumption and operating costs.
Redundancy strategies should also be carefully considered. Operating multiple smaller UPS units at higher load factors can be more efficient than running larger units at lower load factors. By carefully selecting the correct equipment, data center managers can ensure that systems are operating at peak performance while minimizing energy waste. In addition, this approach enhances the security of the data center, as smaller, distributed systems are less vulnerable to single points of failure.
Minimizing the number of voltage conversions and selecting equipment that operates efficiently at partial loads can further enhance energy efficiency. This not only reduces the overall energy consumption of the data center but also ensures that support systems, like backup power supplies, are always available when needed. By reducing energy loss in these critical areas, data center operators can improve overall system reliability and enhance security, as more reliable power systems lead to fewer disruptions and risks.
Moreover, effective electrical optimization allows for better contact with system performance in real-time. By monitoring and controlling electrical components, data center staff can immediately address any inefficiencies or potential failures, ensuring smooth and secure operations. The ability to quickly respond to electrical issues increases the support available for other parts of the infrastructure, making sure everything stays connected and efficient.
These strategies not only improve the operational efficiency of the data center but also contribute to its overall resilience, security, and reliability. By selecting the right equipment, ensuring proper redundancy, and focusing on energy-efficient electrical systems, businesses can reduce both operational costs and environmental impact while maintaining the highest standards of security and support for their data center operations.
Read More: Top 5 Data Center Technologies in 2025: Emerging & Networking - gbc engineers
6. Sustainability Metrics and Benchmarking
Evaluating the total cost of ownership (TCO) and incorporating sustainability metrics are vital for long-term efficiency. Key performance indicators include:
Power Usage Effectiveness (PUE): The ratio of total facility energy to IT equipment energy. A lower PUE indicates higher efficiency.
Water Usage Effectiveness (WUE): Measures the amount of water used per unit of IT energy consumption.
Carbon Usage Effectiveness (CUE): Assesses the carbon emissions associated with data center operations.
Regular benchmarking against industry standards and continuous monitoring of these metrics can help identify areas for improvement and track progress over time.
Read More: Comprehensive Overview of Data Center Design Standards in 2025 - gbc engineers
Ready to Future-Proof Your Data Center?
Partner with gbc engineers to design a facility that delivers performance, reliability, and long-term value.
🌐 Visit: www.gbc-engineers.com
🏗️ Explore Our Services: Services - gbc engineers
Conclusion
Designing energy-efficient data centers requires a holistic approach that encompasses IT systems, environmental controls, air and cooling management, electrical infrastructure, and sustainability metrics. By implementing the best practices outlined in this guide, organizations can significantly reduce energy consumption, lower operational costs, and contribute to environmental sustainability.
As the demand for data processing continues to grow, adopting energy-efficient design principles is not just a cost-saving measure but a strategic imperative for future-proofing data center operations.
With our expertise in structural engineering, BIM technology, and sustainable design, gbc engineers ensures that every project we undertake not only meets the highest standards of efficiency but also aligns with our core values of sustainability and innovation.