< PreviousAs the demand for digital infrastructure continues to increase, new-build data centres and a large estate of legacy IT facilities will be vital in underpinning the ongoing demand for digital infrastructure. The question is, how can we best meet today’s sustainability challenges, alongside the equally important imperative of reducing energy costs? In an ideal world, it would be nice to imagine that any data centre over a certain age would be quietly taken offline and retired – many being inefficient and ill- equipped to deal with today’s increasingly high-density IT demands. However, in the same way, that the switch to electric vehicles allows for a long transition period away from fossil fuel-powered transport, to cushion the impact and, importantly, the cost of such change, the reality of the digital infrastructure sector is that legacy data centres will be required for the foreseeable future. All such facilities are capable of being replaced in a highly ambitious five-to-ten-year period, but the investment required would be prohibitive. Closing down older data centres without replacing them would mean a massive drop in digital infrastructure capacity, at a time when the demand has never been so high. Establishing the exact global data centre population is not easy. In terms of what might be described as the number of data centres owned and/or operated by professional data centre providers, the US International Trade Commission estimates, as of May 2021, a total of some 8,000 data centres globally. However, when considering the hundreds of thousands of enterprise-owned data centres globally – everything from a cupboard with a few servers, right up to large-scale buildings – then the extent of the legacy problem is truly revealed. Let’s not forget that for every Why legacy modernisation is essential to reduce energy costs Andy Connor, EMEA channel director, Subzero Engineering egacy nisation ential to ergy costs greenfield data centre, there’s at least one older facility upon which one may rely. Why does all of this matter? Today, data centre PUEs have come down from an average of 2.5 in 2007 to 1.55 in 2022, but this current figure is still a long way from the ambition of 1.0. If the average is 1.55, that means that there’s a substantial number of data centres that are not even close to that figure as of now, the impact of which comes at a significant financial and environmental cost. Energy costs for the industry have risen massively since January 2021. While the rate of the increase varies from region to region, many countries have witnessed a more than doubling of the cost of electricity. The silver lining to this energy crisis might be the accelerated development of renewable resources, for longer-term cost and environmental benefits, the reality is that, for many businesses, the price of power has become unsustainable. In the data centre sector, where much of the cost of running a facility is the power bill, the impact has been significant. Smarter operators will pass power costs directly on to customers, which on the one hand, provides a haven from volatile energy costs, but on the other, it risks customers moving their business to cheaper or more energy-efficient colos, as the overall operating costs will be cheaper As for enterprise data centre facilities, the rise in energy prices across Europe is equally, if not more impactful, than it is for the colo and cloud operators. After all, enterprises are unlikely to be able to negotiate the long-term price agreements that have, to some extent, cushioned the energy crisis blow for large-scale operators.FEATURES 32 For legacy data centre operators, the energy crisis is even worse. They are not only paying hugely increased power bills but are paying an additional premium through the inefficient use of power. Legacy data centres, for example, waste more than 60% of cooling energy, meaning higher power consumption, and a much higher energy bill than is necessary. Thanks to inefficient data centre design, and a lack of truly sealed, air-tight aisles of racks and cabinets, the cooling solution deployed in many data centres is having to work for much longer and harder than it would need to do in an optimised environment. Containing the problem The good news is that legacy data centres have a roadmap which can take them a long way on the journey towards minimising their carbon footprint and improving energy efficiency – something essential when considered as part of a wider sustainability programme. The first step is to analyse and understand what’s going on in the data centre today. Without such insight, any attempted improvements will be little more than educated guesses, with no real idea of their likely impact. CFD analysis provides a comprehensive map of how a data centre operates in terms of how effective the existing cooling technology is. It highlights key inefficiencies, such as hot spots, providing an overall picture of where hot air leaks in and/or out of the IT racks, cabinets, and aisles, demonstrating the inefficiency of the existing cooling solution. Armed with this picture of current legacy data centre performance, it is then possible to implement a programme of relatively simple, but extremely effective, measures to bring about a significant improvement. Most notably, the implementation of a comprehensive containment strategy brings with it significant data centre operational efficiencies. These efficiencies translate into significant financial and environmental benefits, saving as much as 30% of the data centre energy bill and offering a reduced carbon impact. The emphasis is on ‘comprehensive’. For example, there is no point in building a containment system around the IT cabinets, if the power cable ingress ducts are not fully sealed as well. Similarly, if a cabinet is not fully populated with hardware, the containment solution will not be effective unless the gaps are closed with blanking panels. Properly designed and installed, containment systems can deliver huge operational and energy benefits to the data centre. Set alongside other measures, such as an optimised data centre configuration, increased use of free cooling where possible and/or increased operating temperatures, as allowed for in the ASHRAE standards, containment systems can improve legacy data centre performance dramatically. Finally, comes the ongoing monitoring and maintenance requirement. Data centres are dynamic environments. The contents of racks and cabinets, hence the power supply required, will change over time. People will go in and out of the aisles, carrying out various tasks and, inadvertently or otherwise, impact the space. The performance of the IT hardware may also change over time, likely generating more heat. The climate outside the data centre will impact the environment inside. In short, there are many ongoing variables in terms of data centre performance, and, at the most basic level, the IT load could vary dramatically on a daily basis. Making modernisation work Measure, contain and monitor is the mantra for an effective legacy data centre modernisation programme. Whatever the size of your data centre, understanding its current operational performance gives you a baseline from which to plan any improvements. Any such improvements will need at their core a commitment to a comprehensive containment solution. And ongoing monitoring and maintenance will ensure that the newly upgraded and optimised legacy data centre continues to run as energy efficiently as possible. Optimising performance from an energy efficiency standpoint brings with it much-needed financial savings at a time of energy price volatility. Further, by using less energy, not only does a data centre cost less to run, but also enhances its sustainability credentials. Properly modernised and optimised, legacy data centres can continue to support the ongoing digital revolution and be seen as part of a sustainable, green future, and will no longer be seen as the industry’s environmental Achilles heel.FEATURES 33FEATURES 34 Planning and installing with remote power categories for PoE Anyone working with installation who needs to support power over ethernet should be looking at remote power categories RP1 to RP3, the latest remote power standards from EN 50174-2 (for Europe) and ISO/IEC 14763-2 (globally applicable). These provide project managers with essential guidelines and requirements when designing PoE installations – and adhering to them will avoid significant trouble in the future. What can we do to ensure remote power compliance? What benefits does this bring in the short and long term? During planning and installation, the selected remote power category needs to be considered. Of course, the selected cabling products must meet the requirements, but this is less of a challenge. The average permitted DC current in any given cable bundle in the network installation determines the RP category - the higher this is, the greater the current that can be handled. Every time a PoE device is connected, compliance with the maximum permissible current must always be checked. With RP3, cabling is already configured during the planning phase so that all cables can transfer the maximum PoE current at the same time. This makes the system very safe. Fast growth of PoE drivers We expect that eventually, practically every contract will specify that RP3 category-compliant solutions are to be applied for newly built systems. The fast rise of smart buildings, smart city infrastructure, and all the IoT-related equipment that supports this, is a huge driver for PoE. We’re seeing fast-increasing consolidation of functionalities on a structured cabling backbone within buildings, and this will rapidly expand to encompass groups of buildings and networks. The most recent type of PoE - 4PPoE - can supply up to 90W on each PoE port (with a minimum of 71W at the powered device). This allows support for devices such as laptops or TVs. Assurance that the cable bundle will not overheat is essential for RP3 compliance. Every cable in a bundle needs to fully support PoE at the highest level and every cable in that bundle must be able to carry that burden simultaneously. However, undue resistance unbalance will increase the RMS current of a cable and therefore invalidate the RP3 calculation and planning. The challenge for the planner is to ensure that the attenuation budget for data transmission can always be adhered to with RP3 cabling and that the permissible temperature in the cable is not exceeded. This can be achieved for example by adjusting the link lengths. The shorter the cable link, the lower the resistance, heating and attenuation losses during data transmission. By Rod Arnold, sales manager UK, Geoff Dear, technical manager UK&I, Fatholah Zaki, LAN & data centre sales manager - R&MFEATURES 35 Avoiding resistance unbalance Differences in resistance between wires in cable pairs are widespread in LAN cabling, which can have a negative effect on the delivery of PoE. Unbalanced resistance in a cable pair, or between cable pairs, may be caused by substandard cable and connector manufacturing, poor installation practices at the point of termination, or unreliable termination technology that degrades over time. In the worst case, unbalanced pairs can introduce signal transmission failure due to induced insertion loss in transceivers. The signal transformers of active equipment can easily be saturated by the DC current and fail to receive data sent along lines if the power is mismatched on that Another issue (albeit less serious) is heating of cables and the Power Sourcing Equipment (PSE) which supply DC power and data connectivity. This can reduce equipment lifetimes, waste power, and lead to unreliable power provision. The thermal loads can only remain in check if resistance unbalance is minimised. Fortunately, resistance unbalance testing verifies the deviation in resistance between each of the cores in a twisted pair. However, although ISO 11801- 1 (6.3.3.7. Direct current resistance unbalance) defines maximum resistance unbalance figures, it specifies this element to be tested as optional. Testing offers insight into pair resistance unbalance, which expresses how much the DC resistances of the conductors of a pair differ from each other. Due to the critical nature of resistance unbalance in links requiring remote powering, this test may become mandatory in future editions of the standards. Previously, the advice has always been to test the permanent link and then attach standards compliant patch cords. However, this may present problems for PoE, if cords and their connectors present resistance unbalance errors that are not tested as part of the complete channel. Therefore, we strongly recommend testing the complete channel in any system, with the patch cords in place. To use tested permanent links without surprises, one would need to choose specifically specified patch cords that have been designed to prevent resistance unbalance. For example, patch cords with IDC termination will ensure a reliable, low resistance wire termination over the entire service life of the cord. Fortunately, test equipment manufacturers are currently making it possible to test beyond the basic requirements of standards such as ISO/IEC 11801. FEATURES 36FEATURES 37 Selected devices now provide options to test for additional parameters. With PoE becoming increasingly widespread, supported by developments in systems convergence and ‘all over IP’, field testing is more important than ever. Resistance unbalance testing ensures installations support PoE without introducing data transmission issues or excess heat, making it vital to warranty agreements and avoiding costly equipment replacement and rework. Future-proofing PoE today We’ve seen installations with multiple panel lighting fixtures drawing over 70W each - if heat generation is not correctly managed, that brings vast issues. Previous PoE versions powered much smaller devices such as IoT sensors and actuators, so this was much less of an issue. Whereas many buildings don’t use PoE-powered lighting today, they will in the future, and to ensure that the network is capable of supporting that, you need to ensure Remote Power category RP3 compliance today. Although the standards were introduced in 2020: there’s still not enough market awareness regarding RP category compliance and people don’t always adhere to the specifications. However, as more and more equipment is introduced that requires 4PPOE, networks incapable of supporting this will be scrutinised and installer contracts re-examined. If RP category compliance in line with EN 50174-2 and ISO/IEC 14763-2 hasn’t been respected, a vast amount of costly and time- consuming rework might be required. If you plan and install with compliance in mind, using suitable products, your cabling system will be able to meet the ever-higher PoE requirements of today and tomorrow. FEATURES 38FEATURES 39 Counting the Cost The financial implications of climate change are taking centre stage. One of the biggest issues raised during COP27 was reparation for the three-and-a-half billion people living in countries highly vulnerable to climate impacts, with the UN chief making a call for progress on adaptation and building resilience to future climate disruption. He insisted that countries need to build on the promises made at COP26 of $40 billion in adaptation support by 2025, with needs estimated to reach more than $300 billion dollars a year by 2030. Adaptation will require far more than handing over funds to devastated communities. From improving food security and providing clean water, to reducing the environmental impact of farming and tracking the risks to life associated with weather events, innovation is now essential. But how can effective change be achieved without a detailed understanding of the current situation? How can farmers manage the transition to a different climate and embrace smart farming or agriculture 4.0 practices without the information required to support more effective methods or the ability to remotely monitor livestock, equipment and soil? Eric Menard, VP, strategy and business, Astrocast on why innovative systems integrators have a key role to play in delivering climate change solutions Delivering environmental value – the SI opportunityNext >