Electrical Review feature: The Evolution of UPS

Leo Craig Gen Mgr Riello UPSElectricity demand is set to double by 2050 but this year is also the EU’s ‘deadline’ for cutting greenhouse gas emissions by up to 95 per cent.

These will be tough targets to achieve and will only be done if major ‘energy efficiency’ changes are adopted by industry. Data centres account for more than seven per cent of the total UK energy consumption – a figure which is only going to rise in the data hungry world we live in. Leo Craig, explains.

The Uninterruptible Power Supply (UPS), when used correctly, can become part of a data centre’s efforts to reach strict environmental targets. Here are four ways the UPS is evolving to help reach efficiency goals…

One: Right sizing the UPS

In 2000, we lived in an era of ‘oversizing and wasting’ – future proofing meant that data centre owners were forced to install much bigger UPS’ to meet capacity for the years to come. Fast forward 15 years and the focus is on ‘reducing and saving’ and this is possible through new UPS technology and improved data centre design. 

Rightsizing a UPS makes it possible to invest only in the functionality required for the current load requirement, minimising up-front costs for capital equipment and maximising efficiency. This ‘modular’ approach allows the system to be scaled up or down to meet future demands. Modular UPS systems can be expanded vertically – provided there is room within the existing cabinet for additional UPS modules. Alternatively, a modular UPS system can expand horizontally with the addition of a further UPS cabinet. Riello UPS recently launched its Multi Power UPS, a modular three-phase double conversion system scalable for any business requirements. Using up to 28 power modules of 42kW each, it gives complete scalability from 42kW to 1176kW.

 Advances in the design of standalone UPS systems has also led to the introduction of smaller-footprint systems and taller cabinet designs. For example, a standalone UPS system at 80kVA can have a comparable footprint to a similarly rated modular component UPS system and in some instances, slightly less. While the modular UPS system can offer a more future-proof approach with right-sizing the load on day one, no UPS should ever be 100 per cent loaded as this leaves no room for expansion and can lead to increased component stress.

 Two: Storing energy in the UPS

Where UPS technology has established benefits in terms of power quality, business continuity and guarantee of power supply, in the future its role as a form of energy storage will become increasingly critical.

There is certainly industry uptake in the notion of energy storage. Electric car giant Tesla recently hit the headlines when it announced a Lithium-Ion (Li-ion) ‘Powerwall’ battery system for storing locally generated electricity. Experts say this technology has the potential to ‘revolutionise’ the energy systems for homes and businesses, and could even mark the ‘nail in the coffin’ for utilities. Tesla stated that about two billion of the Powerpacks could ‘store enough electricity to meet the entire world’s needs.’ These are bold words but they clearly demonstrate the growing interest in using energy storage in the transition to a more sustainable world. There are, of course, other companies developing similar energy storage technologies. Large scale energy storage is being tested in Manchester as part of a European project to develop smart city districts and an ‘energy storage test bed’ has been launched at Newcastle University to store energy from the local grid and test innovative new technologies like super-capacitors and long life batteries.

Using Lithium Ion (Li-ion) batteries with a UPS presents an opportunity to use the UPS as an energy accumulator, allowing the data centre to use stored power during times of peak demand. As Li-ion batteries have greater cyclic properties (10,000 cycles) compared to valve-regulated lead acid batteries (500 cycles) they have a faster rate of recharge which makes them suitable for energy storage applications. Li-ion batteries now give data centres the ability to store sufficient power capacity to keep the data centre running for 30 to 60 minutes or more without having to run the generator.

Three: Integrating UPS into the smart grid

UPS manufacturers are developing products that are smart grid ready so that they can be integrated with alternative renewable power sources and facilitate switching between the grid and solar, while allowing export back to the grid. Smart grid ready UPS’ can independently select the most efficient operating mode based on the status of the National Grid. Riello UPS has invested heavily in developing a number of smart grid ready products such as the Master HP, Master HE and Multi Sentry ranges.

In addition, more and more data centres are taking up ‘triad’ or ‘smart’ contracts with electricity Distribution Network Operators (DNOs) which means that when demand from the grid is high, instead of cutting power from a facility without warning, the data centre receives a request from the DNO to remove itself from the grid and use generators instead to support the data centre. For operators, this not only helps to manage energy costs but also creates an additional revenue stream and offers an opportunity to test the resilient power system in real time with minimal operational risk.

Four: Using the UPS to measure power

As the UPS is continuously monitoring power, it can be used as an effective management tool. Used in conjunction with data centre infrastructure management (DCIM) software, real time information can be collated on the performance of the data centre overall and historical reports can be collected and analysed. This can include for example, measuring the air temperature entering the server racks and the return temperatures to the computer room air conditioners (CRAC). Simple monitoring of just these two parameters enables the data centre manager to firstly ensure that the equipment is actually performing efficiently and that the flow of cooling around the data centre is where it should be and not bypassing the server racks and returning straight to the CRAC. Riello UPS recently launched its Multi Sense power and environmental monitoring software which gives data centre managers an important tool to analyse their environmental performance. Multi Sense offers an events log and graphic display of the main parameters and displays the location and operating status for any given criteria. It also shows run time and maintenance information and detailed real time and historical data reports.

What a difference a year makes…

Statistics from Ofgem indicate that efficiency improvements have already had a big impact on the UK’s energy supply in just one year. At the beginning of 2014, the regulator predicted there would be a one in four chance of power cuts this year and next year if no action was taken. That reduced to one in 37 this year as a direct result of energy efficiency measures taken across homes and businesses. This goes to show that energy efficiency methods are working but this is just the start of a long journey in which hopefully industry will see that it does have the power to change.

ESOS is coming…

Data centres should be prepared for one mandatory scheme which will take effect from December – the Energy Savings Opportunity Scheme (ESOS). This was introduced by the UK government in response to the EU Efficiency Directive. The scheme obligates large companies to have four yearly energy audits from which detailed reports on energy use and the efficiency of their organisation will be produced.

ESOS will affect companies with more than 250 employees or companies with fewer than 250 companies but with an annual turnover exceeding €50m/£40million. Failure to comply with ESOS could result in fines up to £50,000 and / or an additional fine of £40,000 in daily penalties – much more expensive than an audit. Companies which do not comply will also be publicly named by the Environment Agency. 

Obligated businesses will be required to carry out this assessment and reporting process in each four year compliance period, ending on 5th December 2019, 2023, 2027 and so on. It is worth being aware that if a company is approved to the energy management standard, ISO 50001, then they do not need to comply or take any actions under ESOS or need ESOS audits. However, they are still required to register with ESOS.