Can we make the internet less power-thirsty?

So much of what we do every day involves a data centre. Shopping online, streaming TV shows, reading this story - they all need data to be stored and readily available.

The immediacy and convenience of those services is great, but that comes at a cost.

Data centres need huge amounts of electricity to keep them going - a large facility will use as much electricity as a medium sized town.

The situation is particularly acute in Ireland, where a relatively small electricity grid is hosting a ballooning number of data centres.

More than 20 of these are in Dublin where Microsoft and Amazon have built very large sites.

Altogether the nation hosts 75 data centres with 11 more under construction and, according to energy consultants Baringa, they could take up 27% of the national electricity output by 2029.

That alarming demand for electricity has forced the Irish government to take action.

Sustainability is now a pre-condition of approval for new data centres with the government stating that "new-build data centres must be able to flexibly reduce power consumption".

Technology is being deployed in the hope of making data centres less of a burden on the power grid.

A new facility, opened at Grange Castle on the outskirts of Dublin, has its connection to the electricity grid managed by software from the firm Eaton.

If the wider electricity grid is under stress, the electricity to the data centre is shut off and back-up systems immediately kick-in.

All data centres operate sophisticated stand-by systems that keep them running in case of any electricity outage.

The first line of this defence is Uninterruptible Power Supply (UPS) devices. These are effectively sophisticated batteries that cut right in the split second they're needed and run for enough time to allow a diesel generator to kick in or for mains power to be restored.

At Grange Castle, Eaton's UPS intervenes and frees up power on the grid when the grid's electrical frequency, measured in hertz, fluctuates in a way that indicates it is under stress.

This might be when power from unstable sources, such as Ireland's vast wind farms, dips.

Many data centres already remove demand from the grid for a pre-defined period using established technology from companies such as Schneider Electric and Vertiv.

But the Grange Castle arrangement is claimed to be the first time a live, dynamic relationship has been established between a data centre and a national grid.

Ciaran Forde from Eaton is a physicist who specialises in data centres. He says Eaton's system acts like a pressure valve pulling the data centre off the grid for valuable interludes.

The owners of the data centre get paid for this flexibility by the Irish grid operator.

Jay Dietrich, from the Uptime Institute which certifies data centres for resilience and reliability, says that income is probably the primary reason that data centre owners are keen to be flexible.

"They're not doing this for noble reasons. They are doing it for cash flow and revenue," says Mr Dietrich, whose career has involved working on energy policy and climate change at IBM.

Ireland provides a snapshot of a global problem.

In July 2022 London's governing body, the Greater London Authority, wrote to housing developers in the west of the capital warning they could face prolonged waits before new developments could be connected to the grid.

Despite a housing shortage across London, new residential projects could face a delay of a decade because data centres in the Thames Valley were hoovering up electrical capacity leaving the gird unable to guarantee power for London's growing population.

How did we get here? Eaton's Mr Forde says it is really down to the explosive growth of cloud computing - the trend which has seen companies outsource much of their data storage and processing to third-party firms like Amazon and Microsoft.

He points out that using the term "cloud" is highly misleading, as it is "a very physical thing".

The cloud does not float in the atmosphere, it consists of computer servers with a vast appetite for electricity.

The Irish example highlights how a combination of environmental concerns and worries about capacity in the grid have triggered a race to save the reputation of the data centre industry.

New technology fixes are being developed.

At Brunello, a town near the Swiss border in Northern Italy, data management business Pure Storage is putting a data centre on a digital diet by trimming bits and bytes and junking surplus information.

Storage devices at Brunello use software that spots when information is duplicated unnecessarily and deletes that material. This process of perpetual review and removal restrains ballooning volumes of data.

It sounds like a mundane job for the IT department, but this program is tackling the data centre industry's biggest enemy head-on. It is reducing the horrific appetite for electric power that characterises all data centres. Pure claims it can slice as much as 80% off a data centre's power usage.

Pure executive James Petter, who came to technology via the British Army and Coca-Cola, takes a blunt approach to the problem of power consumption and has no illusions about how important this is.

"We design our equipment around the principle of lowering power use. And right now all the requests we get from prospective data centre customers are about power consumption.

"They used to ask about technology and price first, but today carbon emissions and renewables are what count. It's all about carbon footprints, everyone's on the bandwagon."

He says that this trend has taken off in the past two years as energy consumption rose to dominate "the CEO agenda". Speaking from Riyadh he describes how the last three data centre providers he spoke to in Saudi Arabia were all deeply concerned about their carbon footprint.

Mr Petter is reluctant to concede that there might be a limit to how much data we can store. "The macro trend is for data to increase. I do think innovation will continue, there will be new ways of storing the data."

It's not in the technology industry's commercial interest to impose limits on how many photos we all store in the cloud.

But if data centres want to win planning permission and maintain public approval they will have to concentrate on imaginative moves that slash their enormous power consumption.