Data centre going green with eco design

While many data centre owners have complained about the EU carbon tax regime for data centres, it has done nothing to slow the rate at which they are being built. Globally we are in the middle of a vast build out which shows no signs of slowing down. Cloud is a key driver for the expansion of data centres, especially as governments start to crack down on data residency.

Companies moving to cloud are often told that one of the unpublicised benefits is that they can lower their carbon costs. This plays well in the enterprise space as companies look to beef up their environmental friendly credentials in shareholder statements. The reality however is that cloud providers are already adding in carbon taxation costs to the price companies pay for access to cloud services and infrastructure. In a competitive market however, those same cloud operators are realising that while they can pass on costs, there is a need to improve their own bottom line.

Last month, Google and Apple announced separate renewable energy deals as part of their commitment to fighting climate change. Apple intends to spend $850m (£571 million) to buy solar energy for the next 25 years. Google, who has so far spent well in excess of $1 billion (£672 million) in renewables has signed a 20-year deal for wind capacity. Unfortunately, these are the exceptions when it comes to the widespread use of renewables to power data centres.

At the Datacentre Dynamics Converged conference held at CeBIT, Ari Kurvi from Russian internet giant Yandex talked about their latest data centre which will open soon in Mäntsälä, Finland. Like Apple and Google, Yandex is keen to show off what it is doing and to position itself as a responsible data centre provider. The challenge for Yandex is that until Mäntsälä is fully built and the data halls populated, its savings are just projections.

Kurvi chose to talk about the data centre in terms of a heat factory, a view that anyone who has worked in a data centre knows only too well. Mäntsälä is designed to be a free air cooled data centre. There has been a lot of work on this type of cooling, with some successful and others encountering problems with particulates.Further problems that have been encountered with this kind of data centre is corrosion due to sea air, and savings being eroded by the use of additional cooling when temperatures soar.

As part of the Yandex design, they invested heavily in environmental data to understand the implications of where to place the data centre and how best to orientate it to the wind. They have also designed the building to have a roof shaped like an aircraft wing. Kurvi explained that this creates a negative pressure zone on the opposite side from where the air enters. This reduces the need for mechanical fans to extract the air from the building by 6-12 per cent, adding to the savings.

Perhaps the most interesting features, and admittedly one that only really applies in a small part of the world, is the recycling of waste heat to a local power company. Cities in Finland used what is known as District Heat systems where any waste heat from power stations or industrial processes is recovered and reused.

Yandex has installed a series of 30 coils that circulate water that is heated by the air coming from the server. This water is then transferred to a local company Calefa, who use a heat pump to send the water which is not at 36-37 Celsius to the local community. The water is then returned to Yandex to be reheated but the returned water is still at 17 Celsius, hot enough to heat for the Yandex office facility. Kurvi describes this as a perfect win:win for all parties as everyone is consuming waste from each other.

In terms of sustainability, the more dense the equipment in the data centre, the more water can be heated and the more energy can be recovered. At the design load for the facility, Kurvi believes that 75 per cent of the heat from the data halls is wasted energy that can be used to heat water for Calefa to pump away. Higher workloads will mean greater heat waste which can then be used to heat water to higher temperatures, increasing the amount of recycling.

The impact of this is not just to reduce the carbon footprint of Yandex substantially but it also provides a one off reduction in carbon footprint for local energy companies of up to 40 per cent. From a financial perspective, heating and pumping this water costs just 20 per cent of what would be required to heat the water using other technologies.

This is not the only project that Yandex is looking at. The possibility of using wind and solar have been considered, especially as costs continue to fall. With the initial environmental research for Mäntsälä providing detailed information on wind speed and direction, they could use turbines to power parts of the data centre and potentially still have enough left over power to supply to the local grid.

Kurvi was unable to say as and when this would happen, just that it was under consideration. There was also no indication if success at Mäntsälä would lead to Yandex using this as a model for other data centres.

With companies already looking to buy their power from sustainable sources, choosing cloud and data centre providers with this type of environmental credentials would play well to investors and help companies show that they were keen on reducing global warming.