13 minute read
Data Centre Management
David Craig is chief executive officer at Iceotope
When air just won’t cool it
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David Craig believes that liquid cooling of servers is the most energy-efficient way to drive the data centre industry forward as energy use in the sector continues to surge
The data centre market uses massive amounts of energy and water in its role as a key economic and research platform for this data-led era. The last year of corporations shifting to WFH, home schooling and binge-watching content, has witnessed immense growth in data generation and consumption.
The market will continue to experience huge growth partly due to online device installation up from 18.4bn devices in 2018 to 29.3bn devices expected by 2030. To support this expansion the network of data centres continues to grow, and with it, the power, cooling and connectivity that maintains it.
Gartner predicts that public cloud services will grow to a $368bn market by 2022, with all major countries experiencing between 15 per cent and 33 per cent growth.
Furthermore, the growth of small edge data centres, typically drawing up to 10kW per site, will require a roll out of tens of thousands of units across individual countries to monitor, analyse and take action on specific applications such as intelligent road and vehicles, hospitals and many more.
The Uptime Institute recently stated that, average data centre PUE in 2020 was 1.58. This has not significantly improved in the last seven years. Many data centre developers are still wedded to a chilled air-cooled approach to technology spaces, which rolls out the older style fan assisted servers. This legacy approach consumes large amounts of water and up to 30 per cent of the data centre’s energy in cooling reducing the total IT load available. A more enlightened approach whether in data centres or at the Edge is chassis-level precision immersion liquid cooling technology, which has a significantly lower PUE 1.03.
Liquid cooling is 1,000 times more efficient than air cooling and
Liquid cooling of servers is the most energy-efficient way to drive the data centre industry forward
eliminates the requirement for refrigerants. It also removes the need for server fans while dramatically increasing the compute density that can be effectively managed in each server rack. Within the technology space liquid cooling within HPC environments allows guaranteed operational temperatures within tightly configured server clusters.
The classic design of a data centre is to use cool airflow across the hot components within server racks to maintain the operational temperature within the technology suite. It is often the case that more energy is used to power the mechanical systems to cool the technology hall than is used to run the servers, ITE and network equipment. At a time when AI (Artificial Intelligence)based applications require highperformance computing (HPC), air cooling and the excessive water it uses is no longer the most effective strategy to cool the technology suite. Pressure from investors, customers, legislators and the public is causing the industry to rethink data centre cooling strategy.
Template to optimise energy
Liquid cooling of servers is the most energy-efficient way to drive the data centre industry forward. It provides a template to optimise energy use in the technology suite, so more power drives the applications on the servers, rather than the cooling systems. As local ‘edge’ data centre designs are implemented, these too benefit from liquid cooling technology over air cooling techniques, in what are much more constricted spaces.
Today’s view on sustainability and reductions in CO2 from data centres is partly driven by the cost considerations as energy and water become more expensive and less available, as well as the threat of legislation to reduce emissions. Also, the massive increase in AI and ML (Machine-Learning) applications which require HPC and graphical processing unit (GPU)-rich servers to process compute-dense workloads has increased the average server power usage from 5kW/rack to upwards of 15kW/rack and in instances like Iceotope’s Ku:l 2 up to 42kW/rack. These HPC configurations no longer work effectively with air-cooled processes.
The HPC market was valued at $39.1bn in 2019 and is expected by research companies to grow at a compound annual growth rate (CAGR) of 6.5 per cent from 2020 to 2027. This market is also referred to as supercomputing and involves the use of increasingly large parallel processing clusters to throughput the data at high-speeds and accuracy reducing results timescales. This capability is making HPC a must have for many corporations, governments and research facilities, which is contributing to the market’s growth.
As new-build and legacy data centres consider the requirements to accommodate HPC environments, with their concentrations of servers, the heat created must be effectively removed and dealt with. Precision immersion technology can now capture and efficiently reject over 97 percent of the heat generated.
Liquid cooling techniques have become more flexible in the devices that can now be accommodated into the systems. To greatly increase energy efficiency in legacy data centres it is possible and cost effective to retrofit chassis level liquid cooled servers in similar racks in the technology suites. In fact, a shared space can greatly increase the efficiency of the space. It is not unusual that technology suites layouts have void spaces where the air cooling is not effective. These areas can be used by liquid-cooled technology, increasing the total space utilisation, creating a more efficient suite.
Data Centre Management
Jack Bedell-Pearce is chief executive officer and co-founder at 4D Data Centres
The conundrum of going green
As we become more environmentally conscious as a society, it is of paramount importance that we push for more sustainable business practices, believes Jack Bedell-Pearce
For the average individual, being more sustainable may amount to taking on more eco-friendly habits, such as recycling and reducing water consumption, or investing in electric or hybrid vehicles. It’s all about making small adjustments that will amount to bigger results in the long run.
In recent years, there’s been noticeable public and shareholder pressure on corporations to prove they’re taking the necessary steps towards tackling climate change, mainly by publicly setting goals on how they plan to reduce their carbon footprint and embrace a more sustainable vision.
One good example is the IT industry, which is routinely looking into effective ways to minimise electrical power generation from fossil fuels, as well as improve waste management and water conservation. However, IT also happens to be a sector that is in constant expansion, predominantly due to our increasing reliance on digital tools and platforms, which means that reducing energy consumption presents something of a conundrum, especially when it comes to data centres.
IT sector and so it is vital that, as growth continues, so do the efforts to become more sustainable.
For the data centre industry, which is single-handedly responsible for at least 1 per cent of global energy consumption, sustainability takes on a more intense and innovative path.
If we think of these hubs as the core of connectivity, data storage and processing, as well as a variety of business-critical applications, it is only natural to believe that data storage and internet use are only set to increase in the years ahead.
We must therefore work to ensure we keep energy consumption at sustainable levels using green
The last year has shown unprecedented growth across the IT sector so efforts to become more sustainable must redouble
technology in data centres. After all, we’re growing ever more dependent on the kind of technology that’s driving innovation, such as 5G, IoT and machine learning, all of which require data centres to operate.
It could even be argued that data centres have an ethical responsibility to be champions of change, and therefore take on the crucial role of implementing measures that minimise the impact that data storing is having on our ecosystem.
Accelerating change
There are many steps being taken to address the energy usage of data centres, but this process will need to be accelerated if consumption is to be kept to a minimum, especially when considering that data usage increased by 47 per cent just in the first quarter of 2020, during the first COVID-19 lockdown. As we try to predict what the future might look like post pandemic, in the short term at least data usage will remain high.
Data compression is one example, which facilitates far greater levels of efficiency especially when incorporating advancements in cloud technology. The process involves the reduction of a file’s size by re-encoding the file data to use fewer bits of storage when compared to the original file.
The main advantage presented by data compression is that a compressed file requires less time for transfer and consumes less network bandwidth. By diminishing file size, data transmission time and communication bandwidth, less storage capacity is required, which results in decreased energy consumption, increased productivity, as well as significant cost savings.
Immersion cooling, on the other hand, represents a more practical measure for addressing challenges around energy inefficiency. The process sees computer components or even full servers being immersed in a dielectric liquid that enables higher heat transfer performance than air.
This solution was recently adopted by 4D, which installed a highly energy efficient “pod” at its Gatwick site that uses immersion cooling technology. The “pod” uses a biodegradable dielectric fluid – that has half the density of water – and heat exchangers to cool down IT equipment. The fluid is kept cool by using intercoolers and water, via an internal heat exchanger that extracts heat from the fluid and redistributes it into chill water, which is subsequently pumped away and cooled down again in 4D’s adiabatic cooling towers, a similar process is used in the automotive industry.
Harness renewable energy
Another sustainable option for data centres is harnessing renewable energy sources. With electricity being the primary source for running daily operations, a single data centre’s environmental impact will be largely determined by where it gets its electricity from. This means that, depending on their resources and location, there is scope for data centres to implement a set-up that relies more on environmentally friendly energy sources, such as wind, solar or even tidal.
Data centres have a real opportunity to drive long-lasting change by embracing sustainability. Committing to a green agenda is obviously a step in the right direction for any organisation but, to become a truly sustainable company, business owners need to ensure energy efficiency is at the heart of every aspect of a data centre’s daily operations.
By sourcing the most sustainable materials and technologies for designing and maintaining these energy-intensive hubs, business owners are able to run their data centres in a smart, efficient and clean way, ensuring that their impact on the environment is minimised as data consumption continues to thrive.
Chris Wellfair is projects director at Secure I.T. Environments
Data Centre Management
Many routes to efficiency
Learn what is happening in your data centre and don’t make any assumptions. Chris Wellfair looks at the challenge of improving energy efficiency
The amount of technology businesses now rely on is immense. The connected nature of business means that we are not simply providing IT systems for staff to use, our businesses are connected to the rest of the world in a way that relies on real-time information and a level of granularity and transparency that has never been seen before. The data centre has truly become the heart of most businesses, even gaining responsibility for systems that would have previously sat elsewhere, such as CCTV/alarm systems, telephony, Internet of Things and building control systems.
While our thirst for technology has grown, we do have to start the conversation about improving data centre energy efficiency by recognising that every single year computing hardware gets smaller, faster and more energy efficient. This is great news when organisations hit their natural hardware refresh cycle, but that is not a ‘get out’ – hardware is only efficient when used efficiently. We see lots of situations where there are racks of servers that might be running at only 10-20 per cent utilisation. There are some very easy wins to be had when it comes to improved energy efficiency in data centres by consolidating appropriate loads on servers and those servers into fewer cabinets. So, start by conducting a load analysis of your servers to learn where those efficiencies could be gained.
Another opportunity for a quick and relatively inexpensive win is to switch light sources in the data centre to LED. That may mean just changing bulbs, or it could be a strategic decision to switch from being a ‘lights on’ data centre to a ‘lights out’ environment, where intelligent motion tracking LED systems are used to only light the area of a data centre in which motion is taking place.
When designing a data centre, take account of its evolution as cabinets move and grow and loads change
The use of radio frequency sensors and tags has become much more common in data centres over recent years. The technology is easy to retrofit in existing data centres, and because of its small size can be used in small spaces, such as tightly packed cabinets. It is very useful in environmental monitoring for everything from basic temperature and fluid detection to differential air pressure, current and voltage sensing. The wireless nature of RF devices is particularly attractive for in-rack environments where clutter and cable dress can be a constant battle. It can bring a whole new level of detail and understanding to what is happening within individual racks – information that will be critical to identifying energy saving opportunities.
Design for efficiency
When a data centre is designed, it should always be approached with energy efficiency in mind, and the best equipment for that task. But just like the servers, the equipment required to keep the DC running also improves with each generation. Over time, the data centre will also physically evolve as cabinets move, numbers grow, and loads change. This all impacts the cooling requirements and efficiency of the space. We need to recognise this and take action to see how it impacts energy efficiency, as yesterday’s design may not meet today’s needs. Sometimes we are forced to rethink cooling systems because they reach end of life or regulatory changes, but it is a good idea to periodically conduct a full assessment of the cooling system and wider data centre energy efficiency. Advances such as liquid cooling, now deliver extremely efficient cooling directly to the CPUs in a server.
When it comes to expanding or upgrading an aging data centre, it is now possible to squeeze so much compute power into a small space, that a room or series of large cabinets may be overkill for your data centre goals. Smaller form factors offer many advantages in overcoming site location and budget challenges, along with rapid build times and lower running costs. They are also extremely energy efficient.
These micro data centres, as they are known, come in a range
of sizes, and include all the same technology that would be expected in a dedicated data centre or larger facility including cooling, environmental monitoring, UPS, CCTV/access control and even fire suppression.
A direct liquid cooled micro data centre can handle as much as 80kW, which is impressive, but only if you need to handle that load – small units starting at a height of 24U can handle up to 7kW, and still retain the same support technology. These new options, sometimes mean that fully functional and resilient data centres can be hidden away into tiny spaces and disguised to sympathetically fit into an open office environment. Units can even be IP66 rated so they can be located outside if required.
As the old proverb goes “there is more than one way to skin a cat.” This is as true for energy efficiency in the data centre as anything else. The most important aspect of improving efficiency is to learn what is happening in your data centre today, not make assumptions, and consider your future plans when making any investment. Getting this aspect of your organisation’s sustainability plans matters as much as anything else, and it certainly matters to your customers.
