Embracing sustainability

6 mins read

Just how sustainable are data centres and what are the new energy-saving technologies being embraced as tech giants look to invest in a more climate-friendly infrastructure?

Investment in ‘clean’ energy for large scale data centres has been going on for years with the likes of Microsoft, Amazon and Google committing to more sustainable operations – last year Microsoft said it would be looking to use more solar and wind power, for example.

Consequently, tech companies are now investing in next-generation technologies that might be able to deliver significant energy and carbon savings, which will be critical at a time when industry and the public alike are becoming more aware of the environmental impact of their consumption.

Take video usage as an example. In 2023, according to new research from Research Rethink Technology, global energy consumption of video hit 3,398 TWh annually as streaming and short form video have become increasingly popular and new forms of video consumption from live events, to watch parties and interactive education and training are set to further boost demand. All of this is putting immense strain on data centres and the energy they require to operate leading to calls for ‘greener streaming’.

However, how seriously some of the big tech giants are taking this issue remains open to question.

While companies are pledging to be more energy efficient and to keep their data centres cleaner, many are exaggerating their sustainability gains by using the purchase of renewable energy credits and carbon offsets to make over-inflated claims about their levels of sustainability.

Does this mean that data centre operators aren’t taking the issue seriously? Well, no. Many are embracing cleaner and greener operations, but the industry could certainly be doing more. In truth, while sustainability is a key priority for many, for others the priority is the bottom line and less their carbon impact. Others are focused on skills shortages and being able to attract enough engineers to the sector.

But while that may be true Sophia Flucker, Managing Director, Operational Intelligence, speaking before last month’s Data Centre World held in London, believes that that while those issues are important, “Sustainability and the imperative of acting in a more environmentally friendly way are now driving investment. There is certainly a business case for that investment too, and policy is influencing it as well.

“IT will make the biggest difference to the sector. For example, making power and cooling systems more efficient, and there’s certainly more we can do to improve IT’s performance.”

Flucker makes the point that the sector also needs to bring more ‘circulatory’ to its supply chain.

“Data centres use a lot of critical materials in PCBs, for example, and there’s a significant environmental impact there, which is not as visible as it should be,” she suggests.

According to Flucker the advent of artificial intelligence, big data and the Internet of Things will result in the need for even more computational power which will, in turn, increase the demand for energy.

“Hopefully increased demand will be offset by greater IT efficiency,” believes Flucker. “It’s a challenging and interesting sector to be in but we do need to build in much greater adaptability and flexibility.”

Organisations that are looking to design or upgrade their data centres to better embrace sustainability are encouraged to consider a number of design factors in achieving net-zero data centre emissions.

For one, they need to conserve energy better - employing air containment and liquid cooling for example. Organisations are also being encouraged to invest in more sustainable computer processing hardware, uninterruptible power supply (UPS) systems and innovative cooling systems.

Critically they need to embrace clean renewable energy sources, such as solar and wind, but while there is also growing interest in leveraging hydrogen as a power source for data centres, with around 99% of hydrogen still derived from fossil fuels according to the International Energy Agency (IEA), cleaner alternatives will need to be developed.

While energy consumption is at the heart of delivering more sustainable data centres, there is also growing awareness of the role of water consumption, too. Several companies including Amazon, Google and Microsoft have made commitments to becoming water-positive, meaning that they will make more water available than they consume - water plays a critical part in the management of data centres as it’s used to prevent over-heating in facilities that incorporate thousands of ICs to process data.

Technical innovation

When it comes to computing resources, such as CPUs, they are increasing in density and power output each year and while they may be delivering faster speeds and increased workloads, they need more power which creates more heat.

With more hyperscale and traditional data centres coming online over the coming years there will be a need to provide more power and the need for more cooling will increase, which will put additional pressure on those all-important sustainability targets. 

While Intel recently announced an effort to create a reference design for immersion cooling, a technique that involves immersing servers and other equipment in non-conductive liquids to enable hyper-efficient cooling, scientists from Nanyang Technological University in Singapore (NTU Singapore) have invented a more sustainable and green method for cooling down servers in data centres, which could potentially reduce both energy costs and carbon footprint by as much 26 per cent. (Pictured left)

The hottest component in a server is the central processing unit (CPU) which currently requires a dedicated air-cooled heatsink for heat dissipation.

Above: A close up of spray nozzles used to cool down CPUs of a server

When servers are stacked together in a rack vertically, they produce a substantial amount of heat, so cold air is required to be drawn in to cool them. The hot air is then expelled to the surroundings, explaining why data centres have to run on energy-intensive air-conditioning systems to lower air temperatures.

The new method developed by NTU consists of an enclosed spray-cooled server rack capable of operating near atmospheric pressure, a water pump, sprays with multiple nozzles over each CPU, a collection system to collect the vapourised liquid, and an energy-efficient room-temperature condenser to convert the gases back into liquid again. Unlike conventional air-conditioning systems, no chiller system is required.

Spray cooling has the potential to carry away more heat than air cooling, which will allow for CPUs to run faster and perform better, and a spray-cooling prototype has been shown to be able to dissipate significantly more heat, handling rack densities as high as 23kW per cubic metre.

If spray cooling is adopted industrially, it’s likely we will see higher computing power servers packed into a smaller space than current data centres. The NTU team estimates that it could translate into space savings of 30 per cent when compared to conventional data centres that use air-cooling systems, a significant advantage for land-scarce countries like Singapore.

Studies by the team showed that based on a data centre IT load of 1 megawatt, their spray-cooled system (see the image above) could save up to 1550 tons of CO2 emission annually when compared to conventional air-cooling systems - given that most data centres consume 1000 kWh per metre square that would see a significant saving.

A spokesperson from AFTERSHOCK PC, Singapore’s largest high-performance custom personal computer builder and which is collaborating with NTU on another sustainability project, said that “spray cooling technology offers superior cooling capability, and this certainly helps to unlock the full potential of computing chips and graphics card currently in the market by overclocking beyond its normal operating range.”

Currently, data centres use a mixture of cooling techniques to dissipate the heat away from hardware and in the coming years both AI and automation are likely to be employed to better manage cooling systems.

CPU design

Considerable work is also being undertaken into CPU design and AMD in partnership with 451 Research recently conducted research that found that improving core processors would have a massive impact on a datacentre’s carbon footprint and would help to keep power costs in check.

The survey found that nearly half of IT decision-makers already recognise that IT operations account for most (25% of respondents) or all (19%) of their environmental impact and have set specific targets to reduce it – so digital transformation is seen as having a massive impact on the environment if not managed carefully.

According to AMD, in 2019 alone, if datacentres and server rooms in the US represented a country, that country would rank above Mexico in terms of total energy consumption – so the issue is not a small one!

According to the research choosing the right processor, that utilises fewer physical servers, is one way that enterprises can reduce overall energy consumption and improve operational efficiency by reducing datacentre footprint and power consumption. Both AI training and high-performance computing applications running on accelerated compute nodes are seen as key to saving billions of kilowatt hours of electricity and reducing the power required to operate systems efficiently.

Data centres

Soaring fuel costs together with climate events have added weight to the need for data centres to transition from being carbon-intensive to being more carbon neutral and sustainable by design.

It’s not just about building more environmentally sound data centres but ensuring that waste is better managed, and designers will need to find ways to optimise asset and resource lifecycles by moving away from single use designs, and embracing recycling, reusing, and remanufacturing.

Designing using a modular approach is increasingly popular as it is seen as a better way to manage growth while avoiding over-provisioning.

When it comes to IT and innovation it is certainly fast paced and unpredictable, according to Flucker.

“The issue with much of the research in this space is when will it go mainstream and could I end up jumping too soon, which could put me at a competitive disadvantage.”

Much of the debate around sustainability is whether sustainability and scalability are compatible with cost effectiveness.

According to Flucker, “They’re not in conflict. I think a common myth is that sustainability is more expensive and that you have to compromise on reliability. That’s simply not possible as you cannot, as a data centre, compromise on reliability.”

Flucker points to designs that use air cooling which she suggests, “Dematerialises the size of the electrical infrastructure and there’s a good business opportunity in using it. But at the end of the day with reporting and policy pushing businesses towards employing more renewable energy and requiring a strategy that embraces and delivers sustainability companies will no longer have a choice. There really will be no option other than to embrace a more sustainable form or operation,” she concludes.