In the race to satisfy voracious demand for computing power, data centre managers are feeling the heat.

That is not just a figure of speech. Power-hungry servers packed into IT facilities are sending temperatures soaring, says Tom Bradicich, vice president of IBM’s systems and technology group.

“Companies are constantly introducing new servers with faster processors, increased memory, and greater storage. This equipment consumes more power and gives off more heat, so it’s no surprise that data centre thermostats are hitting all-time highs,” he says.

High temperatures, however, tend to make servers crash. In order to keep machines cool, Dr Bradicich says, equally power-hungry air conditioning systems must be added to the mix.

With energy prices rising at about 30 per cent annually, however, the corporate electricity bill is starting to generate a different kind of heat – a heated debate over the amount of power that IT is consuming.

“For the first time, the IT department is suddenly being asked to account for its share of energy bills, and to think about how it might go about reducing its share. Quite frankly, that’s come as a shock to many IT managers,” says Andy Butler, an analyst with Gartner, an IT market research company.

For a start, they are starting to think more seriously about server running costs, says Reza Malekzadeh, vice president of international business development at VMWare, a virtualisation software company.

“Plummeting hardware prices mean that acquiring a new server is now less a question of capital expenditure and more of operational expenditure. The realisation that the cost of running a server over its lifetime will outstrip its upfront cost many times over is starting to really hit home,” he says.

The situation is set to get worse. Right now, energy accounts for less than 10 per cent of the average IT budget, but within five years, it will rise to more than 50 per cent, according to analyst estimates.

Power and cooling are not just a burden on costs – they also exert a hefty environmental impact.

Analysts at IT analyst company Forrester Research have calculated that a data centre with 2,500 servers – relatively small compared to many – will use enough electricity in one month to power 420,000 homes for a year. This issue has not escaped the attention of legislators and regulatory bodies. According to Mr Butler at Gartner: “Data centres are a clear contributor to greenhouse gas emissions, which makes them an easy target for legislative and regulatory initiatives.

“It can only be a matter of time before the carbon footprint associated with a company’s data centre is as tightly regulated as the disposal of redundant computing equipment is today,” he predicts. That suggests that a shift in thinking – and in computing architectures – is urgently required.

Fortunately, key technologies have emerged in recent years that, combined, promise huge reductions in data centre power consumption. These are virtualisation, autonomic (or self-managing) computing and multicore processors.

All three will be key to building the data centre of the future, says Paul Miller, vice president of marketing for industry standard servers at Hewlett-Packard.

“In this environment, distinctions between individual applications, servers and network components will blur,” he says. “Instead, computing power will be seen more as a utility – one that can be switched on and off according to need, in a more power-efficient way.”

Virtualisation is key to this vision, as it makes it possible to run more than one application on a single machine.

By consolidating application workloads on to fewer, more highly utilised servers and storage devices, many companies are reducing the number of physical servers in their data centres and thus their energy requirements, says Reed Smith, global product manager for EDS, a server hosting and systems integration company.

That is a great start, he says, but today’s virtualisation technology is in its infancy, and the benefits in terms of power savings will be far greater when it can be applied across the data centre, rather in isolated pockets as it is today.

“In future, virtualisation will provide a level of abstraction so complete that data centre managers will be able to take a single, transparent view of all the processing power at their disposal,” he predicts.

That capability, combined with recent advances in autonomic computing, could lead to serious energy savings, says Bruce Lynne, director of server and tools technology at Microsoft UK.

“Now, much of the work that’s involved in provisioning servers and scheduling workloads needs to be carried out by systems administrators. Autonomic computing enables this work to be performed automatically, according to predetermined business rules,” he says.

By building rules around power usage issues, and allocating workloads accordingly, companies will be able to slash energy bills, says Mr Lynne. “For example, you might build a rule that says that, during periods where applications are idle – perhaps overnight, for example – they should automatically be allocated to a particular server, so that others can be shut down entirely,” he says.

Eventually, say industry pundits, high levels of data centre automation will enable organisations to decouple the physical engineering from the logical management of IT services entirely.

That will mean data centres can be moved offshore where power is cheaper or put close to sources of natural energy – dams or windfarms, for example.

Technological advances in microprocessors, meanwhile, will help to conquer the performance limitations presented by today’s software-only approach to virtualisation technology, which makes it inappropriate for many applications, especially those with high input/output requirements.

Chip manufacturers Intel and Advanced Microprocessor Design (AMD) are working on building virtualisation into their products. “These kinds of chips won’t replace virtualisation software, but will work in tandem with it to eliminate performance degradation and open the doors for new applications to be virtualised,” explains Margaret Lewis, AMD’s director of commercial solutions.

At the same time, she adds, multicore processors – which combine two or more independent processors into a single package – are making it easier for companies to consolidate many small servers on to fewer, more powerful systems and thus to reduce power consumption: “A server built on a quad-core processor will give companies a number of options when it comes to virtualisation: they can decide to run more virtual machines on a single server; or the same number of virtual machines, but with the ability to support more users; or the same number of virtual machines, handling more transactions. It all depends on what the business needs to achieve.”

The data centre of the future is some way off – but forward-thinking companies are exploring ways of reducing the power consumed by their data centres.

BT, for example, recently used virtualisation technology to consolidate 1,503 servers into just over 100, and slashed its energy bill by about £600,000 per year.

“Power consumption very much guides our thinking these days,” confirms Tim Oldham, an infrastructure architect at the company. “In fact, our rule of thumb when it comes to servers is: if it’s near end-of-life, get rid of it. If not, virtualise it. Fewer servers using less energy is definitely the way forward.”