Simon Prichard, Product Strategy Manager at Mitsubishi Electric, explores how energy efficient cooling and heat recovery technologies can help transform data centres into eco-friendly powerhouses.
Demand for data centres is growing. The introduction of hybrid and remote working models, alongside the rapid deployment of technologies such as artificial intelligence, means these buildings are fast becoming a cornerstone of the new digital economy – with the industry now set to grow by 10% per year until 2030.
However, the transmission of vast amounts of data also requires a lot of energy, and data centres are responsible for around 3% of all global carbon emissions as a result. This means we must find ways to cut energy use and reduce these buildings’ environmental impact if we are to reach the goal of net zero carbon emissions by 2050.
Significant steps are already being taken to decarbonise data centres around the world, and the technology is available to help run them more efficiently. For example, a significant amount of data centre emissions comes from keeping equipment cool, so opting for more energy-efficient cooling solutions is one way we can lower the environmental impact of these buildings. Making use of heat recovery can also improve energy efficiency, by using the otherwise wasted heat from data centres to heat nearby homes.
Significant progress is already being made
Awareness of the environmental impact of data centres is growing, and an increasing number of countries around the world are implementing legislation designed to reduce data centre energy use. Ireland, Germany, Singapore, and China have all recently introduced various restrictions covering energy use during construction and operation. For example, Germany’s Energy Efficiency Act, legislated in September last year, establishes targets for energy efficiency during these two phases. Under the new regulation, data centres will be required to reach a Power Usage Effectiveness of 1.2, with owners being advised to avoid and reduce the amount of waste heat generated from these buildings.
The UK government is also moving to decarbonise data centres. The Building Regulations now require the owners and managers of commercial properties, including data centres, to reduce the carbon emissions of these buildings by 27%. The government has also recently introduced the Green Heat Network Fund (GHNF) incentive, which offers funding for projects using waste heat from data centres to heat nearby homes.
With countries worldwide introducing targets for energy efficiency in these buildings, it’s crucial that data centre owners and managers now take action to ensure they are met. But how can this be done?
Energy-efficient cooling is important to consider
Cooling is responsible for around 40% of a data centre’s overall energy consumption, so it’s a key area to consider when reducing energy use in these buildings. However, when deciding which energy-efficient cooling technologies to install, every building will have different requirements, depending on factors like size.
Water-cooled precision air conditioners are ideal for edge-computing or high-density data centres that generate large volumes of heat. These transfer heat generated by IT equipment to chilled water, lowering the temperature of the surrounding building. Air cooling is another potential option, which uses a Computer Room Air Handler (CRAH) or Computer Room Air Conditioner (CRAC) to allow hot air to travel out of the server. This then cools the surrounding space while lowering overall energy use.
Installing a fan wall can also cool your data centre by providing targeted airflow to the surrounding environment. This can match airflow to the specific heat load of the data centre, reducing energy consumption while also keeping IT equipment operating at optimal temperatures. These systems are better suited for hyperscale or colocation data centres with a higher IT load but can also be scaled to the specific size of your building.
Re-using waste heat can also play a role
Another way of lowering energy use is via heat recovery, which uses the waste heat from data centres to heat nearby buildings.
Technologies such as heat pumps can be useful here. The heat output of data centres is around 30°C-35°C, and heat pumps can use water at this temperature as a heat source and increase the temperature to 70°C or 80°C. This heat energy can then be used to heat nearby homes, or to supply domestic hot water to commercial buildings such as gyms or hotels to help meet fluctuating demand.
Heat networks can also be used to distribute some of the waste heat from data centres to homes in nearby towns and cities. These distribute heat and hot water from a central source to surrounding buildings via a large network of pipes, improving energy efficiency while supporting the transition to more sustainable home heating. A key example of this is the Old Oak and Park Royal Development Corporation (OPDC), which has recently been awarded £36 million from the GHNF to create a new district heating system. Once developed, this will use the heat from nearby data centres to provide heating to up to 10,000 West London homes.
With data centre use growing exponentially, we must find ways of reducing their energy use and impact on the planet – and build on the significant progress that has already been made. Opting for energy-efficient heating and cooling technologies can decarbonise our data centres and ensure we are paving the way for a more sustainable data centre industry for all.
