Managers need to know the true cost of emergency power

A few years ago uninterruptible power supplies (UPS) were largely just the domain of data centres and the emergency services, now with the UK facing potential grid power cuts due to under capacity, from 2014, even the smallest companies are installing UPS as standard. However, some of the systems that have been installed are energy inefficient, causing a conflict with the green agenda.

Ian Tucker, managing director of Borri, European manufacturers of high efficiency, 1kVA – 1MVA UPS systems, explores the economic and environmental challenges facing facilities managers

Facilities managers are now tasked with implementing ‘leaner’ solutions, whilst still safeguarding their buildings and cutting costs. With sustainability and environmental matters becoming increasingly important, it’s vital to not only install the right solution for the building but also to know the efficiency rating of the equipment. It almost goes without saying that the vast majority of UK business is now heavily reliant on IT solutions and, with the real threat of a nationwide ‘energy gap’, reliable back-up power is more critical than ever before.

Ambitious energy reforms set out in the 2008 Climate Change Act have created a situation where there is a need to replace large parts of the UK’s power generating infrastructure with nuclear and renewable energies such as wind power. Although some new nuclear power stations are in progress, these won’t become fully operational until at least 2018. With a number of existing nuclear power stations due for decommissioning in 2014, there is now a serious risk of grid power cuts over the coming years.

As a starting point, facilities managers need to quickly reassess their current power protection systems to safeguard buildings against the future deterioration of the UK’s power supply.

To ensure the most appropriate and reliable UPS systems are chosen, reputable manufacturers and suppliers of UPS solutions are placing a lot of resource into educating the industry on emerging UPS technologies, their extended capabilities and the true cost of power.

Design of UPS units has evolved considerably over the last few years but many users remain under the illusion that compromises on protection still need to be made in order to achieve high efficiency levels.

Traditionally, users have chosen transformer-based systems to ensure the highest levels of protection but this type of equipment is renowned for its power inefficiency. However, recent technology advances now mean that some transformer-based UPS solutions can achieve the same high efficiency levels of standard transformerless systems. With a massive 95 percent efficiency rating, energy savings from an ECO UPS are typically between £4,000 - £60,000 (40 – 600kVA) per year, which over the lifetime of the equipment is a substantial payback.

These high efficiency savings can only be achieved if the right UPS solution is selected. When choosing, facilities managers need to take a number of factors into consideration.

The first is the core requirement of the UPS. Does the building support critical loads? If so, then a centralised UPS solution would be the most appropriate, in particular for new builds, to ensure constant protection across all running equipment.

The next question is what is the power load and how long does the building need to be selfsustaining? For heavy on-going power over a number of hours a combined generator and UPS might be the most appropriate solution.

If new equipment is being retrofitted or part of the load doesn’t require constant power support, smaller distributed UPS systems might be preferable. However, distributed UPS arrangements can be more costly and efficiency levels are not as high, so if a large number of units are required it is best to first seek guidance from a reputable supplier.

There will inevitably be a need for investment in switchgear and cabling. With this investment being significant and copper prices rising daily, reducing the sizing of the cables is important for reducing costs. Using a UPS with an IGBT input rectifier significantly reduces the amount of harmonic distortion (THDi) generated, meaning cabling can be reduced typically by up to 25 percent. Fortunately the introduction of efficient UPS with low THDi (less than 3 percent) means that the investment in switchgear and cabling is far less.

For buildings consuming over 20kW of power a three phase UPS solution is typically recommended. However, this does depend on the building’s wiring and power consumption therefore a single phase solution may be better suited.

Ultimately, the correct UPS solution depends on the building’s application and ensuring that whichever UPS system is implemented, it is correctly configured and suited to handling the specified loads. Poor configuration can be a cause for single points of failure.

Don’t forget to check the efficiency of the equipment under partial load conditions. Most UPS efficiency figures are quoted at 100 percent load, however a UPS would never be specified to run at 100 percent capacity, typically it will be specified for 60 percent to allow for peak loadings or future growth, so the efficiency of the UPS at 60 percent load is a far more important figure. It’s also worth highlighting that as energy prices continue to spiral, the electricity cost of running an inefficient or obsolete UPS could be many times greater than the initial cost of the equipment, over its lifetime.

To allow proper maintenance it’s imperative that the UPS solution is fitted with the correct isolation switches and wrap around by-pass, to enable part of the equipment to be disabled for regular servicing. From service work undertaken on other firms’ installations it’s still amazing the number of systems we find that need, sometimes costly and involving downtime, reconfiguring to allow correct maintenance.

It is also important to consider the role of generators, their regular servicing must include running them at full power load for a number of minutes every few months and the impact these will have on fitted UPS systems.

It has been found that many companies are still under specifying their requirements due to a lack of knowledge about what can be achieved from a UPS, the implications of poor configuration, deficient manufacturing and deceptive warranty promises. These oversights can cost a large business millions if an unexpected power failure causes immediate shut down.

When choosing equipment it is essential to look at where the UPS is manufactured, for example only equipment manufactured in the EU comes with a legally bound guarantee that forces the producer to provide service parts for up to 10 years.

Most reputable suppliers are now providing products with a three year manufacturer’s warranty, if it’s less than this you really need to question what faith the supplier has in its own equipment.

It also goes without saying that the supplier chosen must have adequate technical backup and be able to provide lifetime maintenance of the UPS system and have a nationwide team of engineers capable of providing support at short notice.

Always get upfront maintenance costs for the first five years to avoid hidden price hikes, it’s not unusual for some suppliers to sell the initial UPS at cost price, only to make the profit on extortionate maintenance costs throughout the lifetime of the UPS.

On a more positive front businesses can now save money on the replacement of existing inefficient UPS equipment, thanks to the introduction of the Government’s Enhanced Capital Allowance Scheme (ECA) which includes tax incentives and, for certain sized firms, interest free loans from the Carbon Trust.

To qualify, the equipment must be officially listed on the government’s Energy Technology List (ETL). This highly sought after approval means that organisations and businesses needing a UPS can not only save money, but also meet their corporate environmental obligations.

Anyone planning a new build or the replacement of an existing UPS should initially have an energy audit carried out and a handful of UPS manufacturers are now offering these for free.