How green is a green data centre?

The public has become increasingly aware of data centres over the last few years. In parallel, there has also been a steep increase in public awareness of environmental issues.

Despite this, the idea of a green data centre has not been taken up by the media yet. This is set to change. The data centre industry needs to be ahead of the game and get its green credentials in order before it rises to media and public attention.

At the very high levels, there is some recognition of this. The recently announced RenewIT initiative by the European Commission is an example. This aims for 80 per cent of the European data centre industry to be powered from renewable and sustainable resources. This indicates an increasing awareness of the data centre, its green profile and how much room for improvement still exists.

Organisations and consultancies specifying and buying data centre services have become more aware of green operations. Larger organisations often have written environmental policies and those will be reflected into their buying decisions. Green data centres are here because the customers want them and operators must respond to that.

However, many data centres are still operating inside organisations on a legacy basis. Often, no-one is really in charge of them and nobody considering the environmental impact. Gradually, those are being replaced and, often, the organisation migrates to a cloud or hybrid cloud implementation. That migration removes the activities taking place in the old communications room and moves them to a professional data centre. The professional data centre will certainly be highly focused on environmental efficiency.

Cloud computing has a more far-reaching impact on green data centre issues. Moving an organisation’s IT and communications operations from an environmentally inefficient in-house communications room to an environmentally efficient professional data centre is likely to reduce its carbon footprint and environmental impact.
Even within a professional data centre, the process of steadily increasing environmental efficiency goes on, as new equipment comes onto the market and new ideas gain ground. Even the most state-of-the-art data centre will only stay that way for a moment in time. Once that moment has passed, it needs upgrading to the latest standards and thinking.

Cooling systems are a good example. Ten years ago, almost all data centre cooling systems were direct expansion (DX) systems and the suppliers of such systems designed for the minimum capital cost because the buyers bought the cheapest unit that would do the job. Electricity consumption and energy efficiency were a secondary consideration and the decision making was about financial comparisons and benefits. Today, energy efficiency is the primary selling point for DX chiller manufacturers. No data centre designer installs a chiller system without knowing its COP (Coefficient Of Performance – the ratio of energy moved to energy used to move it). The UK government offers tax relief for purchases of equipment with a COP better than a pre-set threshold, currently around 3.0 depending on configuration. Any sensible data centre operator will be continuously reviewing and replacing equipment to keep up.

Environmental considerations are not just energy efficiencies. Most data centres use diesel generators for back-up power. Whilst they may not be running for a high percentage of the time, they can be a significant source of pollution, especially in urban areas, where the inability to dissipate pollution quickly can be a problem. Older diesel generators generate huge clouds of black smoke on start-up. Biodiesel can be used, reducing the carbon footprint of diesel engines, but it needs more care and more frequent cleaning. Again, a data centre operator needs to keep updating to stay in line with his environmental responsibilities.

The green data centre is here to stay. Rising public awareness of green issues and the drive for environmental responsibility mean greenness is no longer a selling point which differentiates one data centre from another, but is an essential fact of life for everyone involved with data centres. Being green requires significant on-going investments, but the benefits are not just to data centre operators but to the global community as well.