How to Reduce Your Data Center's Energy Consumption: Complete Guide

Why Do Servers Consume So Much Energy?

Servers are designed to operate continuously, providing storage, computing, and data processing services 24/7. For this reason, they are equipped with powerful processors, power supplies capable of handling high loads, and internal cooling systems or fans that ensure proper functionality. This combination of components results in a permanently high energy consumption.

Additionally, the traditional design of many data centers tends to over-provision infrastructure. To prevent potential failures or demand spikes, more servers than strictly necessary are installed, which eventually leads to a significant number of machines running at a fraction of their actual capacity. Even with a low workload, each server still consumes power from the power supply, generates heat, and requires cooling.

Another influencing factor is the need for backup and redundancy systems. Many organizations implement high-availability policies, creating redundant clusters where additional servers are prepared to take over in case of failure. While this improves resilience, it can increase overall energy consumption if not efficiently managed or periodically reviewed for the actual need for such redundancy in each area.

The concept of "technological inertia" also comes into play. Sometimes, new servers are acquired or kept running without optimizing the use of existing ones or retiring those that no longer serve a real function. Organizations may hesitate to make changes, as shutting down servers and migrating services requires planning and poses potential temporary risks. However, failing to address these issues means keeping outdated machines consuming resources almost continuously.

For all these reasons, it is crucial to develop strategies on how to reduce energy consumption by focusing on server optimization and rational use. In the following sections, we will explore key measures that any IT administrator or company can implement to significantly cut energy costs and environmental impact.

Consequences of High Energy Consumption: Costs and Sustainability

A data center with high energy consumption not only leads to enormous monthly expenses but also affects the organization's sustainability. On one hand, electricity bills skyrocket, directly impacting business profitability. On the other, every kilowatt-hour used generates CO₂ emissions, especially if the energy source is fossil-based.

In a context where more companies aim to “go green” or at least reduce their carbon footprint, maintaining inefficient servers is a significant problem. Moreover, public awareness of corporate social responsibility is growing. Customers, partners, and suppliers may highly value initiatives aimed at reducing environmental impact, while they may frown upon companies that waste energy and resources unchecked.

Another key factor to consider is the need for cooling. The more energy servers consume, the more heat they generate. This necessitates powerful air conditioning systems, doubling the total electricity consumption. In fact, studies indicate that cooling can account for up to half of a poorly optimized data center’s electricity bill. Reducing server power consumption translates into lower thermal load and, consequently, reduced cooling system usage.

The combination of these factors (electricity costs, carbon footprint, corporate image, and cooling overhead) makes optimizing energy consumption a strategic priority. The long-term financial impact can be substantial, but it is also a crucial step in aligning your business with sustainability trends. It’s important to remember that the European Union and many other countries are increasingly enforcing energy efficiency regulations, so staying ahead can help avoid penalties and unlock funding or incentive opportunities.

Shutting Down or Retiring Inactive Servers (Zombie Servers)

One of the first and most effective measures to reduce energy consumption in a data center is identifying and shutting down so-called zombie servers—inactive servers that provide no relevant services. Various studies estimate that up to 30% of powered-on servers are underutilized or have no real workload, wasting energy unnecessarily.

Why are these inactive servers kept running? Often, they are machines that once hosted a service, remained as a backup, or were part of a now-defunct project. However, they continue to run “just in case” they are needed someday. This precautionary approach can be costly, as each idle server not only consumes electricity but also generates heat and takes up space.

The solution lies in conducting an audit and monitoring process. First, create an inventory of all physical and virtual servers, checking CPU loads, RAM usage, and network traffic. Identify whether they are actually in use, and if not, decide whether they should remain on standby, be consolidated into other machines, or be shut down. Many data centers find that a significant number of servers can be powered off without affecting operations.

It is crucial to implement this initiative with proper planning, especially in environments where the role of each server may be unclear. A common practice is the pull the plug test: unplugging a suspected inactive server and waiting to see if any issues are reported. If no one complains about missing a service or resource, it confirms that the server was indeed a zombie server.

The potential savings are substantial. Shutting down these servers reduces direct power consumption and heat output, which in turn eases cooling demands. To put it in concrete numbers, estimates suggest that each inactive server could cost hundreds of euros per year in electricity bills, not counting maintenance and hardware renewal costs.

Benefits of Virtualization and Workload Consolidation

Server virtualization is one of the most effective techniques for increasing energy efficiency. It involves running multiple virtual machines (VMs) on a single physical server using a hypervisor (such as VMware, Hyper-V, or KVM). This allows multiple workloads to be hosted on a single machine instead of requiring multiple separate physical servers.

The immediate benefit is consolidation: rather than having servers operating at 10% or 20% capacity, multiple applications can be combined on a single server running at 60% or 70% capacity. This reduces the total number of active machines, thereby lowering overall energy consumption. Additionally, the fewer physical machines there are, the less heat is generated and the less air conditioning is required.

Another key aspect is flexibility. Virtualization platforms allow workloads to be moved between physical servers in real time, without service interruption. This makes it possible to distribute loads efficiently during peak demand but also consolidate workloads onto fewer servers during low activity periods, allowing surplus hardware to be powered down. This approach maximizes installed computing power while avoiding unnecessary energy consumption.

The virtualization process also helps identify underutilized applications or servers. By centralizing resource management, it becomes easier to monitor CPU, RAM, and network usage levels. As a result, organizations can determine how many VMs are truly needed and how many physical servers can be decommissioned. However, care must be taken to avoid uncontrolled VM proliferation, known as VM sprawl. Establishing governance policies and periodically cleaning up obsolete VMs is essential.

Ultimately, virtualization not only reduces energy costs but also simplifies infrastructure management and enhances resilience. Many companies have reported significant savings in electricity and cooling costs, as every eliminated physical server translates into lower power consumption and reduced heat output. For more information on virtualization benefits, visit the official VMware page.

Upgrading Servers with Energy-Efficient Hardware

Hardware upgrades may initially seem like a significant expense, but they often result in substantial savings in the medium and long term. New generations of servers typically incorporate more efficient processors, optimized power supplies, and advanced energy management systems. This allows them to deliver the same (or even greater) performance with lower power consumption.

When discussing how to reduce energy consumption, one of the most effective steps is to replace older, obsolete servers, especially those that have been in operation for several years. These machines often lack the latest energy-saving technologies and, as they age, may also experience increased failures or require constant maintenance.

To maximize efficiency, look for servers that come with energy-saving certifications, such as the ENERGY STAR standard or power supplies with an 80 PLUS certification (Bronze, Silver, Gold, Platinum, or Titanium). These certifications ensure that the server meets certain efficiency standards and minimizes energy loss. Additionally, modern servers often include variable-speed fans controlled by temperature sensors, which automatically adjust based on actual workload.

Another benefit of upgrading hardware is higher processing density. A single new server with multiple CPU cores and large amounts of memory can replace several older servers. This setup saves rack space, reduces electricity costs, and simplifies management. Additionally, transitioning to solid-state drives (SSDs) instead of traditional mechanical hard drives also reduces power consumption and improves input/output (I/O) performance.

If you're considering acquiring next-generation equipment, remember that Licendi offers a wide variety of servers at competitive prices with activation guarantees. In fact, if you need to buy a server to upgrade your data center, their catalog and expert consulting services can be an excellent option. Ultimately, investing in modern servers is justified by continuous energy savings and reduced technical issues.

Key Factors: Power Supplies and Efficient Components

Inside each server, several components determine overall energy consumption. One of the most important is the power supply unit (PSU), which converts alternating current from the grid into direct current for the motherboard, processors, disks, and other elements. If the PSU is inefficient, a significant portion of energy will be lost as heat during conversion.

To prevent this, it's recommended to choose power supplies with 80 PLUS certification in Bronze, Silver, Gold, Platinum, or Titanium levels. The higher the level, the greater the guaranteed efficiency across different workloads. This means that for every 100 W consumed internally, fewer watts are drawn from the power source, saving energy and generating less residual heat.

In addition to the PSU, there are other components worth monitoring:

• Low-power processors: Some manufacturers, such as Intel and AMD, offer CPU lines specialized in energy efficiency without significantly sacrificing performance.
• Low-voltage RAM: Using lower-voltage DDR modules helps reduce power consumption in large installations.
• Hard drives: SSDs consume less power and generate less heat than traditional HDDs while offering superior performance.
• Cards and peripherals: Every additional component (network interfaces, graphics cards, etc.) adds to power consumption. Evaluate whether they are truly necessary.

In a comprehensive efficiency approach, paying attention to these details makes a difference. Heat generated by inefficient power supplies and components increases cooling demands, leading to higher electricity costs. Conversely, by reducing PSU losses and using optimized components, you will see a positive impact on both power consumption and thermal load.

Configuring Power Management and Monitoring Usage

Having efficient hardware is not enough if it is not properly configured. Many servers and operating systems include advanced power management options, but they are not always enabled by default or set optimally. Reviewing these settings can make the difference between a server running at full performance all day and one that adjusts its consumption based on actual workload.

Start with the server’s BIOS/UEFI, where you will often find settings such as SpeedStep (Intel) or PowerNow!/Cool’n’Quiet (AMD). These technologies allow the CPU to adjust its frequency and voltage according to demand, reducing power consumption during low-load periods. It is also important to check power plans in the operating system. Windows Server, for example, offers "High Performance," "Balanced," and "Power Saver" plans. In Linux systems, you can choose CPU governors (ondemand, conservative, performance, etc.) to optimize efficiency or performance.

Additionally, continuous monitoring is essential. Data Center Infrastructure Management (DCIM) tools or specialized software can measure real-time consumption, detect spikes, and analyze usage patterns. Some power distribution units (PDUs) or monitored racks provide power consumption data per outlet, making it easier to identify inefficiencies or servers in prolonged inactivity.

With this monitoring, it becomes easier to identify potential improvements. For instance, if you find that workload is minimal during nighttime hours, you can automate the shutdown of certain servers or migrate virtual machines to allow some equipment to be powered down. Similarly, temperature monitoring helps better manage cooling and prevent overheating that increases fan power consumption.

In summary, power management and usage monitoring are part of a continuous cycle. You adjust settings, measure results, and make corrections if anomalies are detected. Over time, this leads to significant cost savings and a more stable IT environment.

Optimizing Server Cooling and Environment

Although this article focuses on servers, we cannot overlook the importance of cooling in the overall energy consumption of a data center. Every watt consumed by a server turns into heat, and that heat must be removed from the room through air conditioning or other systems. Therefore, improving thermal efficiency can lead to significant savings.

A common practice is organizing racks in hot and cold aisles. In this design, servers' air intake aligns in designated "cold aisles," while hot air exhausts are grouped on the opposite side ("hot aisles"). This prevents airflow mixing and allows air conditioning to operate more efficiently. For even greater efficiency, containment doors or panels can be installed to seal aisles, concentrating cool air where it is needed most.

It is also essential to adjust room temperature appropriately. Traditionally, some data centers are kept at excessively low temperatures (below 20°C) out of fear of overheating. However, many manufacturers certify that their equipment operates perfectly with intake air temperatures around 25°C or higher. Raising the thermostat by just a few degrees can drastically reduce electricity costs without risking operational stability.

Another growing trend is liquid cooling, whether through water circuits or even immersion in specialized fluids. These systems can transfer heat more efficiently than air, reducing the need for powerful cooling systems. While implementing liquid cooling requires additional investment and planning, it can be highly cost-effective in large data centers with high server density.

Finally, do not forget routine maintenance: regularly cleaning filters and fans, ensuring airflow paths are unobstructed, and checking for air conditioning leaks. A data center with optimized cooling will experience lower energy costs and extend the lifespan of its equipment.

The Commitment to Sustainability in Modern Data Centers

Globally, major tech companies are making significant efforts to reduce the carbon footprint of their data centers. Giants like Google and Microsoft have announced carbon neutrality goals and invested in cooling techniques using renewable energy, AI-driven temperature management, and strategically locating facilities in colder climates.

This commitment to sustainability is not just a marketing strategy—there is increasing regulatory and social pressure demanding corporations take environmental responsibility. Additionally, from an economic perspective, being more energy-efficient leads to significant savings. This is why there is a growing convergence between profitability and sustainability, benefiting everyone.

An efficient data center can even transition from being a major heat emitter to a source of useful heat for nearby communities. Some pioneering projects channel residual heat to warm buildings or greenhouses in adjacent areas, maximizing the use of invested energy. This “circular economy” perspective turns what was once waste into a valuable resource.

Moreover, the rise of renewable energy has enabled the emergence of data centers operating under green energy contracts. In some cases, solar panels or wind turbines are installed on-site, reducing reliance on traditional energy sources. These strategies, combined with virtualization, efficient management, and advanced cooling, help achieve Power Usage Effectiveness (PUE) values close to 1, meaning that very little energy is wasted compared to the amount used for actual computing.

In this scenario, server and system efficiency is not just an isolated goal but part of a broader strategy to create infrastructure that is environmentally friendly. Every company, big or small, can join this movement by making improvements to their data centers that benefit both their business and the environment.

Immediate Savings and Success Stories

The benefits of optimizing server energy consumption become evident quickly. For example, shutting down or removing inactive servers can result in thousands of euros in annual savings on electricity and maintenance, even for small businesses. In large organizations, virtualization and workload consolidation have been proven to reduce the number of physical machines required by 50% or more, leading to lower electricity costs and thermal loads.

Companies from various industries have publicly shared their success stories. For instance, major banking institutions have managed to relocate their applications to just one-third of the servers they previously used after careful evaluation and migration. This not only led to cost savings but also streamlined infrastructure management and significantly reduced obsolescence risks.

Another notable example is organizations that have adopted continuous development and deployment methodologies (DevOps) combined with containers to dynamically scale their applications. During peak traffic periods, more containers are activated on available servers, while during off-peak hours, these resources are freed up, even allowing certain physical nodes to be shut down. This level of elasticity is especially valuable for businesses with fluctuating workloads (such as e-commerce during peak seasons).

Some data centers in Nordic countries have optimized cooling so effectively that they achieve extremely high efficiency levels and minimal operational costs. Some even sell their residual heat to district heating networks, monetizing what was once considered waste. This demonstrates that efficiency strategies can sometimes open up new revenue streams or foster collaborations with the local community.

Ultimately, every step counts. From the simplest measures, like identifying zombie servers, to more advanced strategies like liquid cooling or software optimization, all contribute to cumulative and sustainable savings.

A Partner for Upgrades: Licendi

Upgrading your infrastructure is key to improving efficiency, reducing operational costs, and ensuring optimal performance. At Licendi, we offer digital server licenses with activation guarantees and personalized support, allowing you to implement your solutions hassle-free.

Avoid excessive hardware costs and maximize your servers’ potential with original Windows Server and SQL Server licenses tailored to your company’s needs.

Purchase licenses for Windows Server and SQL Server securely and at the best price.

Additionally, at Licendi, we guarantee European-origin licenses with secure activation and expert support to address any questions or issues.

Final Conclusions

In an increasingly digital world that is aware of environmental impact, reducing the energy consumption of your data center is a goal that brings significant rewards. You have seen how servers are at the core of this challenge, being responsible for a considerable portion of energy consumption and heat generation. However, they also present the perfect opportunity to implement improvements that lead to a more cost-effective, reliable, and sustainable data center.

The concrete actions we have reviewed include:

1. Shutting down or removing inactive servers to eliminate phantom energy consumption.
2. Consolidating workloads through virtualization and containers, minimizing the number of active machines.
3. Upgrading to more efficient hardware, with a focus on 80 PLUS power supplies and low-power processors.
4. Adjusting power settings and continuously monitoring resource usage to identify optimization opportunities.
5. Optimizing cooling through hot and cold aisle layouts, temperature adjustments, and potential liquid cooling solutions.
6. Enhancing software efficiency, as well-optimized code and design prevent unnecessary server overloads.

Of course, all of this is part of a broader strategy that encompasses sustainability in data centers. Current trends go even further, exploring the integration of renewable energy, waste heat recovery, and the use of artificial intelligence to dynamically manage demand. Regardless of how far you want to go, every step toward efficiency will result in tangible savings and a reduced carbon footprint.

If you are also looking to modernize your infrastructure, consider upgrading your equipment with a trusted provider. This way, you not only reduce energy consumption but also ensure the reliability and security of your IT environment. We hope this guide has provided you with a clear and practical understanding of the steps to optimize your server consumption, helping you build a profitable, robust data center aligned with the green future of technology.