How Capgemini keeps its Merlin datacentre green and energy-efficient

360-degree view to green datacentre strategy

But why Swindon? “Although technology and latency has moved on, proximity was a key factor in setting up the datacentre because some of our enterprise customers have business applications that are very sensitive to latency,” Hammond says.

The IT team assessed several other locations in the UK and found Swindon to be the most favourable. It is not just cold temperatures that affect the energy efficiency of a datacentre. It is also the quality of the air, the dampness and the moisture content in the air.

“Another key factor was adequate power supply and building the Merlin datacentre on the site of a car factory meant that power supply would not be an issue,” Hammond says.

Capgemini also wanted a site that would help the company minimise construction activity. Re-using the car factory meant it could cut down on environmental damage by construction as well as make use of telecommunications and power infrastructure at the site.

Merlin datacentre’s energy efficiency

The IT team designed the Merlin datacentre with a targeted power usage effectiveness (PUE) of less than 1.1. “It was an over-ambitious target but we are delighted how efficient and green the datacentre actually is,” Hammond says.

Currently, the facility has a PUE of between 1.03 and 1.07. During the winter months when the ambient temperature is cool, the datacentre uses free air cooling to have a PUE of 1.03. A combination of free cooling and use of electricity in summer months takes the PUE to 1.07.

One of the reasons the Merlin datacentre is highly energy-efficient is because of its modular design.

Rather than build a 3,000 square metre datacentre, complete with all the infrastructure required, Capgemini adds datacentre modules containing data racks every time there is demand for additional capacity. 

A modular datacentre is different from a traditional datacentre in that it is a portable infrastructure which is designed for rapid deployment, energy efficiency and high density. It can be shipped to anywhere in the world and set up anywhere that has power sources, network connection and cooling equipment.

But having a vision for an energy-efficient datacentre is just one thing. Getting the go-ahead and investment from the financial department for building a new one in the middle of a recession is more crucial.

“It would always be a challenge to convince the stakeholders to build a new datacentre in the middle of a recession,” Hammond says. But the IT team overcame the investment challenge with its green modular datacentre strategy. “Because it was modular, we did not need all the capital expenditure to build a large, fully-equipped, scalable datacentre,” he adds.

“We just had to make investment in the necessary things such as the site, WAN, CCTV, first module of datacentre rack etc,” he says. Once the site began operations and as more customers embraced it, the team started adding additional capacity.

In addition to using a modular approach, the datacentre’s energy efficiency could be attributed to the team’s clever management and IT strategy.

The Merlin datacentre uses a sophisticated building and datacentre infrastructure management systems from Schneider Electric. “Our datacentre management tools are so sophisticated that it does not just detect problems within the datacentre. A while ago, there was a bonfire nearby and the infrastructure started using other modes of cooling until the air was heat and contamination free,” Hammond says.

One of the biggest datacentre energy-efficiency challenges is that as the density of a facility increases, it starts consuming more power and the PUE rises. But the team at Capgemini has a strategy to overcome this issue.

For instance, if it adds a new module for additional capacity, it uses “blanking plates” that cut off energy supply to that part of the module which is not in use. “By blanking off sections of the racks, we make sure that the air or energy that goes in is used to cool down servers that are in use rather than cooling the full module,” he says.

The team has also developed a technique to ensure that there is no leak between the hot and cold aisles so that energy waste is minimised.

The Merlin datacentre started off with just one of its enterprise customers using it. And three years on, it serves over 15 Capgemini customers from both the public and private sectors.

And the service provider is saving costs on power and is able to pass it on to its customers.

Chris Howes, the head of corporate information services at the Environment Agency, one of its public sector clients, said: “We’re proud to be associated with the Merlin datacentre, where a growing number of our own services are sustainably and securely hosted. Energy efficient datacentres are a vital part of mitigating the carbon cost of IT. Capgemini’s success is a great example, to anyone providing IT services, of how to improve the energy efficiency of datacentres.”

That’s not all. The European Commission has awarded Capgemini UK with the 2013 EU Code of Conduct for Datacentres award for datacentre innovation and energy efficiency. 

The facility has also won other green IT credentials such as an ISO-14001 certification for its environmental management system, a place in the Sunday Times Best 60 Green Companies, and platinum status in the Corporate Responsibility Index published by Business in the Community.

But despite its heavy use of free air cooling, the IT team have made provision for multi-diesel power generators and UPS systems for full resilience.

The IT infrastructure in Capgemini’s Merlin datacentre includes standard x86 servers and IT equipment from datacentre IT providers including IBM, Dell and HP.

Is the Merlin datacentre too advanced for its equipment providers? “We are asking our technology suppliers to design and ship equipment that will fit a modular datacentre,” says Hammond.

“We want them to ship equipment with fewer nuts and bolts as currently we are stripping out a lot of unnecessary pieces before fitting it into our datacentre for maximum efficiency.”

But apart from that the IT team has not faced any big challenges in the last three years. The datacentre has been resilient and has had no downtime, loss of power, energy issues or security problems.

While most of the IT hardware is new-generation, Hammond and his team recently added some legacy IT into the datacentre. “We added mainframes and some legacy storage systems as one of our enterprise customers wanted to run applications that were more suited to the mainframes,” Hammond says.” But that has not changed the efficiency or performance of the facility, he adds.

The Merlin datacentre is now becoming a case study within Capgemini itself with its other datacentres looking to replicate it for cost and energy benefits.

Because of its high performance, reliability and efficiency, the datacentre runs mission-critical workloads such as core SAP and Oracle  business applications for Capgemini’s customers.

“The facility is cloud-ready too”, Hammond says adding that the team is now looking to implement Skysight – the cloud orchestration service jointly developed by Capgemini and Microsoft.

The company is also looking to use some of its Merlin datacentre learning in its other four UK facilities. “We have tried to make our Bristol datacentre a bit more energy-efficient using techniques from our Merlin facility.

“In the future if we build new datacentres or consolidate existing ones, it will be based on the Merlin datacentre blueprint,” adds Hammond.

The demand for Merlin-like energy efficient datacentres will increase as companies become more energy conscious and as power costs begin to bite, hopes Hammond. He is also seeing a change in attitude in CIOs towards green IT.

“Three years ago, sustainable technology and Green IT was just a consideration but it wasn’t followed by enough action,” Hammond says. “But that is changing now with CIOs becoming more interested and making it as one of the key criteria.”

“And it is the public sector CIOs that got to the green IT agenda sooner than the private sector CIOs who are, only now, catching up.”