Modern Building Services

24 MODERN BUILDING SERVICES JUNE 2022 FEATURE VERTICAL FOCUS: ENERGY IN THE TECHNICAL ENVIRONMENT Why are data centre operators embracing green trends? Increased environmental legislation, coupled with record- high energy prices, is putting European operators under pressure. With energy experiencing a supply crisis at a time of high demand, energy-intensive businesses like data centres are eager to take more control over their energy usage. This will help themmeet new legislation on CO 2 emissions, maintain power continuity, and earn income from energy markets. New UPS and fuel cell technologies can provide both power continuity and power to the grid. The technologies also enable data centres to integrate renewable energy and even generate income by participating in demand and frequency response schemes. Using low-carbon technologies also helps to build an operator’s reputation as a sustainable business, helping them stand out amongst their competitors and attract new customers – an important point for the big players in the market. Why is the medium-voltage level beneficial for a UPS system? Data centre UPS systems traditionally operate alongside servers and HVAC equipment at the low-voltage level. However, data centre facilities are becoming larger and more power-hungry to gain economies of scale. As power requirements increase, moving to medium voltage is a natural step for systems. The two primary benefits are increased reliability and reduced costs, but medium- voltage systems provide other benefits too. Operating at 24 kV, medium- voltage equipment is significantly more robust than comparable low-voltage systems as a data centre requires fewer units tomeet its power needs. As individual modules, these units are easier to install, operate, andmaintain than multiple low-voltage systems spread around the facility. This reduces downtime becausemore equipment automaticallymeans more risks. Themedium-voltage approach also has energy efficiency advantages as it runs lower currents, reducing electrical losses. The latest systems boast an efficiency of up to 98%because of its power conversion equipment. Evaluated against a rotary UPS, this higher efficiency can save up to 4.2 GWh per year. This saving equates to 1,245 tonnes of CO 2 emissions over a 15-year life for a large site. Lower currents also produce less heat, so less power is drawn for HVAC systems, further improving the energy efficiency of the entire centre. Since the MV UPS operates at a medium-voltage level at the grid connection point, it’s flexible enough to support loads anywhere in the data centre. This ensures power continuity for servers to remain stable throughout the centre by overcoming short outages and power quality concerns wherever they are. In contrast, low-voltage UPS capacity can potentially become stranded when power can’t be reassigned elsewhere. This may require an additional capital outlay to ensure full coverage of backup power. Furthermore, operating at the MV level saves on additional capital expenditure, as the UPS units can be installed in an electrical roomor substation rather than occupying high-value server room space. Such a locationmakes it ideal for feeding power back into the grid if necessary. Danel Turk , ABB’s Solution Portfolio Manager for data centres, explains howmodular, medium voltage (MV) uninterruptible power supply (UPS) and fuel cell technologies can protect the availability for customers and provide power back to the grid, all while saving energy and carbon emissions. Why next-gen data centres need modular medium- voltage UPS and fuel cells