Until datacentre operators transition their backup generators from diesel to cleaner alternatives, they should not be used to power datacentres for extended periods of time or feed energy back into the grid.
While the UK government’s most recent projections expect massive growth in renewable energy up to 2035, plans to close all the remaining coal plants by 2025 and retire the majority of Britain’s current nuclear reactors by 2030 suggests there is a real possibility of a low-carbon energy gap in the 2030s.
At the same time, datacentres are proliferating to meet the increasing demand for digital data, which will place a greater strain on the supply of electricity. In Ireland, for example, the state-owned transmission system operator EirGrid expects that datacentres and other large users will consume 29% of Ireland’s electricity by 2028.
A report by the Irish Academy of Engineering (IAE) has estimated this datacentre expansion will require almost €9bn in new energy infrastructure by 2027 to cope with the growing demand, which is projected to add at least 1.5 million tonnes to Ireland’s carbon emissions by 2030.
While the UK datacentre market is already well-established and therefore not set for anywhere near the same kind of expansion as in Ireland, if efficiency gains in datacentre technology do not keep pace with the increasing demand for digital data, it could lead to an uptick in the amount of power consumed by datacentres.
On top of this, increasing electricity demand for electric vehicles, internet of things devices and general industrial electrification leaves the door open for an energy gap to emerge if there is not enough new capacity developed for the grid.
To ease the burden on the UK’s National Grid and to plug the expected supply and demand gap, energy companies have previously called on datacentre operators to use their backup generators to exclusively power their sites for extended periods, and have suggested that they could be used to boost the supply of energy flowing through the grid during high usage periods.
However, running datacentres or feeding back energy to the grid using their current diesel generators is not a sustainable alternative, as they would release over double the amount of carbon dioxide per kilowatt hour and significantly reduce local air quality.
To solve the issue, experts on datacentre emissions and power consumption told Computer Weekly that datacentre operators should invest more in large sustainability projects in places where they operate, and think more about access to renewable energy when choosing locations for future datacentres.
The environmental effects of the diesel backup generators
According to Ian Bitterlin, a consultant engineer and visiting professor at the University of Leeds, the carbon produced by operators’ use of diesel generators is “negligible” at best.
This is because, despite their use of diesel fuel, they are only run an average of 12 hours per year, sometimes as a means of generating emergency power, but mostly just for routine testing and maintenance.
“There are 8,760 hours in a year, and the carbon you’ll release for 8,750 of them are whatever the grid supplies,” said Bitterlin.
“For the other 10 or so hours, you’re doubling your carbon footprint by burning diesel. The grid in the UK is roughly 300 grams of CO2 per kilowatt hour, but burning oil in a diesel engine produces about 700 or 800 – it is actually the least efficient way of burning a fossil fuel.
“But 10 hours at 700 grams per kilowatt hour is almost indistinguishable from the 8,750 hours of what you use in the grid.”
Emma Fryer, associate director of datacentres at trade association body TechUK, also views diesel generator carbon emissions as a “real red herring” because of how rarely they are switched on, but added that they can reduce local air quality around the datacentre location due to the release of pollutants such as Oxides of Nitrogen (NOx).
“We are breaching both our national and local NOx levels quite frequently,” she said.
“In local areas, you’re allowed to have around 18 exceedances a year, and some place like London basically get that in a week. So there’s a political sensitivity about air quality, and poor quality does shorten lives.”
Given the concentration of datacentres in urban environments, particularly London, Fryer points out that while the generators are rarely used, if they were all switched on at once “there would be a significant air quality impact within the local area”.
This, mixed with the increased level of CO2, rules out using the diesel generators to power datacentre facilities for extended period of time or feed energy back into the grid, at least until the datacentre industry can offer viable clean alternatives.
What can datacentre operators do?
One alternative suggested by Elizabeth Jardim, a senior corporate campaigner at Greenpeace, is for datacentre operators to look more at using batteries for their backup power.
“This is still early stages and would depend on the local context as far as what’s already on the grid and how are the batteries charged up in the first place, but there is potential to use batteries in datacentres to reduce overall carbon emissions,” she said, adding that the proliferation of datacentres, particularly in Amsterdam and Ireland, is changing the energy demand of these regions very quickly.
However, electric batteries require either cobalt or lithium for energy storage, both of which are environmentally intensive to extract.
Lithium, for example, will generally require 500,000 gallons of water to refine and wash a tonne of it. The Washington Post has reported that the Sales de Jujuy lithium plant in Argentina pumps water at a rate of more than two million gallons per day.
“We urgently need a transition to renewable sources of energy to address climate change, but it can’t come at the cost of more destruction or human rights violations,” said Jardim.
Elizabath Jardim, Greenpeace
“We will need more mineral extraction with increasing demands, but it needs to be done in a way that is much more following best practices, doing engagement with communities in mining areas, and ensuring the transparency and sustainability of those minerals.”
She also suggested that datacentre operators should invest in large-scale renewable energy projects to positively change the energy mix of the locations where they operate, and think about access to renewable resources more when choosing locations for their datacentres.
“We’re already seeing that in some places – Amsterdam, the Scandinavian countries because of the hydro power there, and there’s been a trail of datacentres in the pacific north-west region of the US because it has cheap, abundant hydro power,” she said.
Jardim added the warning that if renewable energy projects become too concentrated in renewable-abundant areas, it would still increase energy demand on local grids.
According to Bitterlin, however, if datacentres want to be sustainable they should limit the amount of IT work they do to things that are valuable or meaningful.
“If you take the argument to the extreme, in 20 years’ time sites like Facebook won’t exist because they’re a frivolous use of carbon and it’s not an essential for life,” he said.
A slow transition for a conservative industry
Bitterlin added the datacentre industry is “extremely conservative” and has therefore taken a very long time to move away from tried and tested approaches.
“It would be a brave man to build a datacentre that wasn’t exactly like the one down the road, because a lot of datacentres are not necessarily for individual companies, they’re co-location, and those ‘co-lo’s’ want to attract customers,” he said, adding that, as a service-based economy, the UK relies heavily on datacentres for work and business.
“One kilowatt hour represents about £150 worth of business. The fuel for one kilowatt per hour costs about 10p, so if I say to you I can save you 50% of your fuel costs for a whole datacentre, it sounds great.
“But if you’re putting at risk the £150 for the sake of 5 pennies, you can see why most datacentres are conservative – we want to save energy, but not at any risk above what we’ve already got.”
In 2018, the MIT Technology Review found that, at the current rate of progress, it will take 400 years to complete the global energy revolution necessary to avoid catastrophic climate change.
This is despite the fact that, according to the International Renewable Energy Agency (Irena), the cost of solar panel electricity systems has fallen by roughly 80% since the end of 2009, while the cost of wind turbine prices has fallen by 30 to 40%.
“The market approach thus far is too slow to address the threats of climate change, and something that would help speed that up would be global or country level jurisdictions saying, ‘Okay, no more using fossil fuels, everything coming in here has to be done renewably’,” said Jardim.
“In places where the government has signalled that, you see the companies getting in line to figure it out much more quickly.”