Why the UPS is vital to the data center?

The importance of UPS systems has grown dramatically in the last decade to the point where they now form an essential component of a data center’s power protection. But what do users most need from their UPS?

A recent survey in the UK, conducted by UPS Limited -UPSL, looked into this question. Here is what it found..

Not so long ago a UPS was perceived as a primitive and intrinsically ugly piece of plant room equipment, more at home amongst its generator cousins than sensitive ICT equipment. Fast forward to today, and the role of a UPS has evolved in direct correlation to the consistent advances in computer hardware –becoming an indispensable resource for the protection of critical applications.
This transition to data center essential has driven UPS systems to become more reliable, efficient, cost effective and flexible.

The growth of the data center market has accelerated the development of UPS systems functionally, especially in the areas of efficiency, availability and flexibility. As loads have grown and become more critical, electrical mains power has become, or is at least seen to be, less reliable, further contributing to the growth in UPS demand. When asked, more than 75% of the 2000 IT professionals questioned reported that their UPS system was called upon to protect critical equipment during a power outage within the last 12 months, with 78% saying they also believed the situation would only get worse over the next decade.

This opinion is certainly not without foundation. It has been predicted that up to 19 GW of UK generating capacity will be lost by 2018, as coal, oil and nuclear power stations are decommissioned and close. Timely replacement of these sources, with those compliant with ‘green’ legislation, will be “challenging” according to the Department of Energy and Climate Change and will likely rely on a significant step change in the level of investment from the private sector and government sponsored renewable energy initiatives.  

The rocketing price of oil, and the direct effect this has on the cost of energy, is also, unsurprisingly, of major concern to 80% of those questioned. Reduction of an organization’s energy usage and carbon footprint is therefore also a growing priority, driven in large part by legislation such as the CRC (Carbon Reduction Commitment) Energy Efficiency Scheme in the UK.

Interestingly the survey shows that more than 63% regard reducing overall operating costs as their main driver to reduce power consumption, compared to just 27% which are driven by a more altruistic desire to reduce their organization’s carbon footprint. Furthermore, purchases of capital equipment are significantly affected, with 82% of respondents regarding energy efficiency as a key buying consideration. This figure includes UPSs, with nearly 54% of those questioned reporting that modern UPS systems – designed and manufactured with environmental considerations at their core – have significantly improved power consumption and cooling issues within their organization.

Transformerless technology lies at the heart of modern UPS design. Its immediate impact has improved energy efficiency by around 5% across the UPS’s whole load span. This substantially reduces energy and cooling costs.
Transformerless UPSs also present a higher and more stable input power factor, which reduces input current and sometimes electricity costs.

Transformerless implementations bring many other benefits through their reduced size and weight. A 120 kVA UPS, for example, can be implemented as a 263Kg unit with a 0.42 sq m footprint instead of an installation with a 1.32 sq m footprint weighing 1,200Kg. This has enormous implications for power protection and has enabled UPS systems to become sets of more attractive rack-mounted modules, operating in parallel, rather than monolithic floor standing units.

The modular design also increases UPS availability because a faulty module can be quickly replaced, typically within about half an hour, compared with the six hours typically needed for component level diagnosis and repair. Modules can also be ‘hot swapped’, without needing to divert the critical load onto raw mains.

Availability is defined by the relationship between Mean Time Between Failures (MTBF) and Mean Time To Repair (MTTR), so reducing MTTR increases the UPS’s availability. Transformerless systems also improve battery reliability through using a DC–DC battery charger which eliminates AC ripple – a prime cause of premature battery failure.

From the users’ point of view, there is an overriding urge to do everything it takes to achieve reliability for their power supply, irrespective of the UPS technology employed. More than 90% of the survey’s respondents said they believe that maintenance and emergency call out services are as important as the hardware itself to their business. This pressure reflects the changing role of ICT equipment within commerce and industry.

Originally, computers were something of a luxury, as they automated tasks that had been performed manually – and could be performed manually again if computing resources were denied for any reason. Today, by contrast, organizations compete in a world where customers expect instant responses to any enquiry or transaction request – and they expect this 24/7, as they are increasingly likely to be working from mobile smartphones or pad devices. Failure to deliver is not a viable option; some companies have gone into liquidation as a direct result of a power failure.

Computer-based equipment, however, has not only become critical for commerce and industry; it is also increasingly ubiquitous.
Equipment that has traditionally been primarily mechanical is progressively changing to being primarily electronic, networked and online. This has increased utility and productivity, but at the same time has widened the scope of systems critically dependent on clean, uninterrupted mains power.

An important example of this is seen in industrial process control and manufacturing operations, where production and quality data can be – and therefore must be – transmitted to managers and customers in real time. Life support and monitoring systems are electronic, so present a critical load for obvious reasons. Other examples include telecommunications hardware such as PABXs and point of sale (POS) terminals.

Online technology allows such services to be enhanced by remote monitoring, where key equipment parameters can be interrogated over a telephone link. This interrogation can be initiated by an alarm event to inform field response technicians about the nature of the fault before they arrive.
Alarm notification of an event as it occurs allows immediate response to an emergency, while the remote diagnosis improves the rate of ‘first time’ fixes after arrival at site.

The survey has shown how UPS users’ concerns reflect our current political, business and technical environment. Inexorable growth in data center demand, coupled with increasing concerns about UK power grid availability lead users to value reliability highly, while viewing reliability as the sum of the equipment and its support.

With rising energy costs and increasingly aggressive ‘green’ legislation, energy saving is also a priority to save costs, and to a lesser but significant extent, meet carbon footprint reduction and social responsibility goals. A large majority of the respondents have carbon reduction
policies and strategies to investigate product efficiencies in place. Modern UPS technologies help users to achieve these goals, but the right choice of supplier is essential as well.