Sustainable design: a holistic approach towards green energy data centres
Data centre power consumption: a growing concern
Data centres are notorious for their high power consumption, mainly driven by the energy requirements of countless servers and networking equipment. According to IEA, the global data centre industry accounts for around 0.9-1.3% of the global electricity demand. Thereby contributing to both operational costs and carbon emissions linked to energy usage. Addressing this issue is crucial for reducing the environmental impact of data centres, gaining social acceptance and moving toward a more sustainable future.Designing green energy data centres
In the era of increasing environmental awareness and the urgent need for sustainable solutions, green energy data centres have gained significant traction. These innovative facilities prioritise energy efficiency, reduce carbon emissions, and harness renewable energy sources to power their operations. Transitioning into a green energy data centre entails more than purchasing green energy; it requires a holistic approach to energy usage. We will explore how green energy data centres adhere to the trias energetica framework, examining the vital strategies and innovative technologies that underpin the development of environmentally conscious data centres. Let’s take a look.
1. Minimising energy consumption
The most effective strategy for achieving sustainable energy consumption is to eliminate the need for energy altogether. Hence, the initial phase of the trias energetica focuses on minimising energy consumption. Three effective approaches to reduce energy consumption that we’ll dive into are energy-efficient infrastructure, energy recovery and recirculation, and strategic considerations for location and site selection.Energy-efficient infrastructure
To minimise energy consumption, data centre design and infrastructure are crucial. Employing energy-efficient servers, cooling systems, and power distribution units can significantly reduce power requirements. Modern cooling techniques, such as hot aisle/cold aisle containment and liquid cooling solutions, enhance cooling efficiency and minimise energy waste. Additionally, using energy-efficient lighting and implementing smart power management systems can further optimise energy consumption.Power Usage Effectiveness (PUE) stands as a pivotal metric in evaluating the energy efficiency of data centres. It represents the ratio of total energy consumed by a data centre to the energy utilised solely for IT equipment. The ultimate goal is to achieve a PUE as close to 1 as possible, indicating the highest level of efficiency. According to The Uptime Institute, the average reported PUE in 2022 was 1.55, reflecting a marginal improvement compared to previous years.
Even though achieving a lower PUE is standardised in the market and has become a key objective in enhancing energy efficiency it does not measure the efficiency of IT devices themselves. To comprehensively evaluate the energy efficiency of a data centre, additional metrics focusing on the IT devices within the data centre such as Data Centre Infrastructure Efficiency (DCiE) or Compute Efficiency Ratio (CER) are often considered. These metrics focus specifically on the energy efficiency of the computing and processing equipment, providing a more detailed assessment of the effectiveness of IT devices in relation to energy consumption.
Energy recovery and recirculation
In a data centre, the energy input generates a substantial amount of heat as output. However, instead of considering excess heat as a waste product, green energy data centres embrace innovative solutions to harness and repurpose this energy.Heat recovery systems can redirect waste heat to provide warmth for neighbouring buildings or to power other industrial processes. While reducing the dependence on traditional heating systems and contributing to energy savings for the neighbouring buildings, this also presents an opportunity for data centres to establish partnerships with local communities and organisations, fostering collaborative efforts towards sustainability.
Implementing heat recovery systems can present infrastructure challenges, particularly when establishing the required heat exchange mechanisms with surrounding buildings. Overcoming these challenges requires careful planning, coordination, and investment in facilitating infrastructure to ensure effective heat transfer.
Another approach is the implementation of efficient air recirculation systems within data centres. These systems leverage the warm air expelled by servers to heat incoming cooler air, thereby reducing the need for additional energy consumption.
Location and site selection considerations
Choosing an ideal location can enhance the energy efficiency of a green data centre. Considering natural climate conditions can help optimise cooling requirements, reducing the need for energy-intensive cooling systems. For example, regions with naturally cool climates, such as the Nordic countries in Europe, can significantly reduce the need for energy-intensive cooling systems because of the lower average temperatures throughout the year. Data centres in these regions can optimise their cooling processes by harnessing the natural cool air from the environment.2. Use of sustainable energy generation
The second step of the trias energetica emphasises the utilisation of sustainable energy sources. Leveraging renewable energy sources such as solar, wind, hydrogen, and geothermal power are sustainable options over fossil fuels. For data centres, harnessing renewable energy sources has long been the standard. It is commonplace to procure renewable energy as their primary energy source. As stated in the IEA report “ICT companies are major purchasers of renewable energy, accounting for half of all corporate renewable PPAs.”However, it is important to be aware of the potential downsides associated with using renewable energy sources. One challenge lies in the integrity of renewable energy purchases. While some may proudly claim to be powered by renewable energy, it is essential to scrutinise the sources and ensure that the renewable energy procurement aligns with genuine sustainability practices. Greenwashing, where renewable energy usage is falsely portrayed or exaggerated through the purchase of certificates or credits, can undermine the true environmental impact of data centres.
To truly promote renewable energy production, it is crucial to move beyond solely purchasing pre-existing sustainable energy. While power purchase agreements (PPAs) can label energy usage as sustainable and environmentally friendly, it is essential to take further steps. Data centres should aim to become genuine green energy facilities by actively engaging in the generation of renewable energy.
Engaging in on-site renewable energy production, with solar panels or wind turbines directly at the facility, is commonly suggested as a green energy supply. However, on-site solar panels often are an insignificant contribution to energy usage and wind turbines are too risky. Experiments are being conducted with hydrogen on-site but hasn’t been a common practice yet. Implementing a comprehensive strategy that combines both (on-site) energy production and responsible renewable energy procurement is key.
Furthermore, data centres can implement energy storage systems, such as batteries or pumped hydro storage, to store excess renewable energy generated during peak production periods. These stored energy reserves can then be utilised during times of high demand or when renewable energy generation is low. Flexibility plays a crucial role in harnessing the benefits of renewable energy sources. Through efficient management and optimisation of renewable energy resources, data centres can enhance their green energy footprint and reduce their reliance on non-renewable sources.
3. Efficient use of fossil fuels
In situations where renewable energy falls short of meeting the energy demand, green energy data centres face the challenges of efficiently utilising fossil fuels. While the reliance on non-renewable sources may be inevitable at times, prioritising their efficient use is crucial. An approach that remains relatively uncommon in the data centre industry but holds promise for optimising fossil fuel usage is hourly matching.
Hourly matching deviates from the traditional practice of evaluating energy consumption on an annual basis and matching it with an equivalent amount of renewable energy purchases. Instead, it focuses on tracking energy usage on an hourly basis. This approach provides valuable insights into the specific hours when the variability associated with renewable energy necessitates the use of fossil fuels from the grid.
This approach enables green data centres to proactively manage their energy usage and make informed decisions about when and how to optimise their reliance on fossil fuels. By aligning energy consumption with renewable energy availability on an hourly basis, the carbon footprint can be minimised while maximising the utilisation of renewable energy sources.
Adopting hourly matching as a practice in the data centre industry requires sophisticated monitoring and tracking systems that can provide real-time data on renewable energy generation, grid availability, and energy demand. With this information at hand, data centres can fine-tune their operations and adjust workload distribution, cooling systems, and power usage to maximise the utilisation of renewable energy while minimising reliance on fossil fuels. Optimising energy consumption based on this information is the next step for green energy data centres to minimise environmental impact while meeting energy demands.
As we conclude our exploration of sustainable data centre design and the remarkable world of green energy solutions, it becomes evident that we are stepping into a greener era of technology. The environmental concerns surrounding the exponential growth of data centres have spurred the development of innovative strategies and technologies that prioritise energy efficiency and reduce carbon footprints. Embracing sustainable practices in data centre design and operations is not only crucial for mitigating the environmental impact but also for shaping a more environmentally conscious digital future.
By adopting a holistic approach to energy usage, green energy data centres strive to minimise energy consumption and maximise efficiency. If you have any questions or would like to learn more about designing green energy data centres, our team of experts is here to help. Feel free to reach out to us for further information, guidance, or assistance in implementing sustainable practices in your data centre operations. Together, we can work towards creating a greener and more sustainable technology landscape.
