Published on Friday, Dec 18 2009 by
Retailers are highly dependent on IT to provide services such as online shopping and EPOS systems. This dependence on IT brings with it rapidly rising power demands and increased costs. However, huge energy savings can be achieved through increasingly efficient UPS systems, explains Alan Luscombe, sales and marketing director at Uninterruptible Power Supplies Ltd (UPSL).
The personal relationship nurtured with customers means that the retail sector experiences higher expectations of its environmental performance than many other industries. While this is met on the shop floor with low-energy store design, eco-friendly sourcing of produce and recycling initiatives for example, energy and emissions targets are a major challenge for upstream parts of the business.
The drive for new technologies that reduce power consumption and emissions has been key to the development and uptake of modern uninterruptible power supply (UPS) solutions that offer significant improvements in efficiency and reduction of carbon and physical footprints.
IT energy consumption has increased by 400 percent per server rack since 2003 and continues to grow almost exponentially. Trying to cater for future needs with traditional stand-alone UPS systems can lead to over-specification, creating a wasteful gap between installed capacity and the size of the actual critical load, and makes inefficient use of costly floor space. However, today’s modular, rack-mounted systems can be right-sized by inserting or removing ‘hot-swappable’ modules, enabling power to be added as requirements grow without any footprint penalty. A traditional standalone parallel redundant system is typically less than 50 percent loaded whilst a modular solution typically achieves a 70 percent or higher loading. This reduces both energy and UPS cooling costs.
Transformerless UPS technology has also made a major contribution to energy efficiency. The new three-phase PowerWAVE 6000 for example features intelligent energy management and has been designed to reduce consumption, generate less CO2 and minimise space requirements. By comparison with equivalent stand-alone UPS systems, it reduces the overall physical footprint of the unit to 0.41m² (up to 100kVA) and 0.64m² (up to 200kVA), providing class-leading power density of up to 250kW/m². Cost savings equal to expenditure on power and cooling can be achieved within a few years of operation.
Right-sizing and flexible growth are key to maximising UPS efficiency. Additionally, post-installation, regular inspection and maintenance also have an important role to play. Tesco for example employs UPSL for preventive maintenance of the high-power UPSs protecting data centres for its distribution network. As well as ensuring that such UPS units can support round-the-clock IT availability, scheduled maintenance helps to optimise their efficiency. Over the lifetime of a system, correct calibration and monitoring/replacement of components can add significantly to energy savings - an important contribution given the challenge of balancing rising IT power demands with cost control and environmental targets.
In addition to large scale power protection at head offices, distribution hubs and data centres, UPS systems also cater for individual stores. A swap-out programme at Waitrose has gradually replaced existing UPS installations at its supermarkets with MINIpowerPLUS units, providing flexible, easy-maintenance support for its EPOS systems. The compact, modular configuration allows cost-efficient output expansion and redundancy within a small footprint, and reduces running costs through high operating efficiency and near-unity power factor.
With scalable architecture and energy saving technology, modern UPS systems of all sizes ensure the highest level of power protection for critical loads, while meeting retailers’ requirements to build and operate energy-efficient and environmentally friendly IT infrastructures.
Power protection case study: mains failure success
Many prominent retail chains in the UK outsource their IT infrastructure and data processing to Retail Assist. A UPS and standby generator supplied and maintained by Uninterruptible Power Supplies Limited protects the power to Retail Assist’s critical systems.
When their data centre experienced an interruption of the utility electricity supply that lasted approximately 18 hours - “The first we knew about it was when one of our night shift operators heard the diesel-generator start up in the early hours of the morning,” said Andy Struthers, technical services manager at Retail Assist. “Despite the loss of power, all of our critical equipment and systems continued to run as if nothing had happened. None of our servers either experienced or logged any unusual event. When the power was eventually restored, the UPS managed the transfer back to the utility supply, the generator automatically stopped and we were once again fully powered by mains electricity.”
The UPS serves two main functions. Firstly it continuously conditions the mains or generator voltage to ensure that Retail Assist’s critical load receives only the highest quality power, and secondly, using its battery back-up, it ensures continuous power to the critical load.
“It’s reassuring to know that the power protection solution performed as intended and that our business operations remained uninterrupted.” Andy Struthers commented.