Building a sustainable future for data centres
In committing to carbon neutrality by 2030, European data centre operators and trade associations have put sustainability at the very top of their agenda
Digital transformation is a power-hungry business: even as our economies and lives become increasingly virtual and data-driven, their real-world carbon footprints also increase. Take virtual currencies, for example, which depend on an energy-voracious system of computer-based calculations to verify transactions. In February, the University of Cambridge calculated that just one of these currencies, Bitcoin, consumes around 121.36 terawatt-hours (TWh) a year – that’s more than the annual energy consumption of Argentina, the Netherlands, and the United Arab Emirates1.
Like cryptocurrencies, many of the virtual processes that define life as we currently know it – email, online shopping, gaming, banking, streaming services, cloud computing, and Software-as-a-Service (SaaS) – also depend on large amounts of energy for their operations. As the world embraces digital transformation even further – through 5G, the Internet of Things, artificial intelligence, and the fourth industrial revolution – the energy consumption of the virtual world looks set to mirror its demand for ever more data, which in turn will translate into a demand for ever more data centres.
Such data facilities provide governments, organisations and corporations with the necessary computing, storage and networking capabilities to deliver their data, services, and applications, while affording the protection of advanced security. Currently, there are an estimated 7.2 million data centres globally, and even though their number has fallen in recent years. This is due to small enterprise platforms being taken out of service as companies place workload into the cloud with cloud companies deploying new efficient large scale data centres.
As this trend is coinciding with a global shift to reducing energy consumption and achieving net zero, improving the sustainability of data centres – which are estimated to consume two per cent of global energy – has become a priority for industry operators and trade associations. This is especially so in Europe where, in response to the European Green Deal – which aims to make the European Union (EU) climate neutral by 2050 – the sector has agreed to make data centres climate neutral by 2030.
For some data centre operators, achieving this goal will require the introduction of measurable and verifiable targets for energy consumption, prioritising water conservation and the recycling of heat, increasing the reuse and repair of hardware, and the use of low-carbon sources of energy.
The industry measures its energy consumption using a metric called Power Utilisation Effectiveness (PUE), which is expressed as a number and represents the ratio of total facility energy divided by the amount of energy that is used to power its hardware and systems. In addition to technical equipment, data centres are also supported by significant facilities infrastructure that keeps their hardware and software up and running. This includes power subsystems, uninterruptible power supplies, backup generators, cabling, and ventilation and cooling systems dedicated to mitigating the heat given off by all this equipment and maintaining an optimal ambient temperature.
The more efficient a data centre is, the lower its PUE score, which can range from 3.0 to 1.2. If a data centre’s score is more than 2.0, it is effectively using more energy to support its enabling infrastructure than it is supplying to its frontline ICT equipment. Such is the industry’s concern about energy consumption that many data centres are being located above the Arctic Circle, where cooler temperatures and abundant hydroelectric power reduce the need for energy and water-hungry support systems.
For Stuart Gray, CyrusOne’s European Engineering Director, however, a sustainable data centre won’t look very different from the one he already operates. “Our design philosophy hasn’t changed for many years, as we’ve always built using the most up-to-date energy-efficient equipment,” he explains. “We use 100 per cent renewable energy across our whole European portfolio and we've been recording water usage in our facilities to the best of our current abilities for a number of years.”
For Gray, the greater challenge lies not so much in achieving more sustainable outcomes, but in demonstrating that this is the case. “How do you put a stamp on this that shows that we’re doing as much as we can within the limits of the current technology?” he asks.
The most recognised sustainability rating in Europe is BREEAM, a method for master planning projects, infrastructure and buildings. “We have said that every new design going forward must achieve a very good BREEAM rating as a minimum,” says Gray.
BREEAM allows CyrusOne to translate the key performance indicators (KPIs) to its construction partners, which are selected because “they share those kinds of sustainability aspirations in the first place,” Gray says.
One such partner is construction management company Structure Tone, which has been working with CyrusOne for the past decade. “What we have seen over the years is the data centre market grow and mature its approach to sustainability and the global and local environment,” says Structure Tone’s Business Development Director Richard Irwin. “It’s the number-one consideration any time we’re engaging with a data centre company.”
CyrusOne worked with Structure Tone on its flagship Dublin Data Centre, which incorporates areas of grassland, wildflower meadows and wetlands. “We always look to put in natural wildflowers and pollinators where we can,” says Irwin. “If we’re engaged early on, we can do this using local knowledge.”
The company’s data centre campus in Arizona in the US restored 40 per cent more water than it used in 2019, returning water to a community in a drought-affected area. On other projects, builders are encouraged to recycle timber on site and use modular builds where possible, and wastewater is collected and measured, along with CO2.
In its 2019 study, Innovation Landscape for a Renewable-Powered Future2, the UN’s International Renewable Energy Agency (IRENA) found that data centres sit at the nexus of energy efficiency, renewable energy and the burgeoning data economy, and that by integrating the latest technologies and renewable energy they have the potential to set an example that other power-hungry industries might follow.
For Gray, that’s a mantle the industry is already assuming. “We’re not just ticking boxes,” he says. “I would say most of the larger organisations in the industry are doing this and doing it in the right way.”