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Backup datacentre power: Using diesel generators to plug the UK's energy supply gaps

Energy market stakeholders are calling on the datacentre community to help them close the UK's energy demand and supply gap by hooking up their diesel generators to the National Grid, but will it work?

With the government committed to closing all coal-fired power stations by 2025, ensuring the demand for energy never outstrips supply is a top priority for the National Grid.

To alleviate some of the supply and demand pressure, the organisation concluded its 2017/2018 capacity auction at the start of February 2017.

This saw it award contracts worth £378m to energy companies across the UK in exchange for a commitment to keep the National Grid topped up with power during times of peak winter demand.

As well as incentivising energy suppliers to do their bit, the National Grid, the government and the big five energy suppliers are also calling on some of the UK’s biggest energy consumers to get involved as well, including the datacentre community.

Ian Bitterlin, consultant engineer and visiting professor at the University of Leeds, says, given the sheer volume of power the datacentre industry consumes, it should not come as a surprise to know its usage habits are of interest to National Grid and others.

“Domestic power consumption has been falling fast and industrial consumption has bottomed out at a low level now that we are an 80% service-led economy. The only growth is in commercial power [use] and a part of that is the 7-10% annual growth in datacentre power,” he says.

“With the UK having 40-50% of all of Europe’s datacentres, the amount of power datacentres consume always attracts attention.”

Sharing the power wealth

Centrica-owned British Gas is actively courting datacentre operators, and pushing them to consider hooking up their backup generators to the National Grid to boost the supply of energy flowing through it during high usage periods.

Operators are also being urged to think about “islanding” their facilities by using their backup diesel generators to exclusively power their sites for extended periods. The idea being that this will reduce the amount of electricity they draw from the National Grid and, in turn, their reliance on it.

Speaking at the Datacentre Summit London in February 2017, Russell Park, head of energy and sustainability solutions at British Gas, confirmed the idea is being piloted by an unnamed colocation provider, as well as a telecommunications company.

“It is early doors, and we were uncertain if [datacentres] was a marketplace we wanted to be in, but we have been proven right. That gives us a case study and a proof point and [gives the industry] that bit of confidence they need to see this is something they can take advantage of,” he says.

Risk versus reward

But will a couple of examples and case studies really be enough to convince the notoriously risk-averse datacentre community that opening up access to their backup power generators is something they should do?

“Datacentre operators are inherently a very conservative group and wouldn’t want to do anything that could jeopardise uptime and reliability,” says Andrew Donoghue, European research manager for datacentre technologies at analyst house 451 Research.

Focusing on availability and redundancy to the detriment of everything else has been the standard approach up to now.

Given the important contribution a functioning and efficient generator plays in mitigating datacentre downtime during power outages, it is scheme some will be wary of participating in, says Bitterlin.

“Focusing on availability and redundancy to the detriment of everything else has been the standard approach up to now”
Andrew Donoghue, 451 Research

That said, there are a few operators involved in similar schemes, he concedes, but they tend to favour the “island” approach because the technical risks associated with connecting to the National Grid are far too great for them.

“Whether ‘real’ or ‘perceived’, most datacentres don’t embrace the concept of taking risk in exchange for money. Starting your generators and running a facility in parallel with the utility does have a technical risk,” says Bitterlin.

“That risk can result in the connection tripping and the generators going offline if the grid suffers an overload. The only reason the generators have been called upon is that the utility is under pressure, so the risk is real and tangible.”

Regulatory pressure

There are also a slew of regulations governing how diesel generators can be used. These are geared towards minimising the carbon emissions and pollutants created when in use, says Donoghue, which might limit the appeal for operators as well.

“Datacentre generators are primarily designed for backup, so if you want to use them in this way, that [constitutes] operational use, and there are other regulatory issues around that,” he says.

“In fact, organisations might have to invest in different types of diesel generator if they want to use them operationally.”

On the regulatory front, Guto Owen, a director at Wales-based clean energy consultancy Ynni Glan, says there are changes afoot that look set to tighten up the rules on using diesel generators even further, which could make it even harder for datacentre operators to participate.

For instance, the UK government’s proposed Medium Combustion Plant Directive (MCPD) is geared towards limiting the amount of air pollution generated by diesel generators but, unlike previous versions, it is targeting smaller gensets too.

“The direction of travel for the legislation is against diesel gensets,” he says.

For this reason, he says datacentre operators should explore the idea of ditching their diesel generators altogether and investing in non-combustion fuel cell technology, because it is exempt from the MCPD proposals.

“While the fuel cells plus datacentre is new to the UK, it is well-established in the US where banks, technology companies and city centre operations and other run their energy-hungry datacentres off cost-effective fuel cells,” he claims.

Environmental impacts

When used as originally intended in a datacentre backup context, diesel generators create relatively little pollution because they are rarely used, says Donoghue.

“They’re typically tested and, if they have to be used in anger, they do not usually have to run very long because the grid should be back up before too long,” he says. “The actual impact from the diesel emissions – compared to other sources of diesel emissions – is pretty minimal.”

If operators start using their diesel generators more regularly, the environmental impact of their activities will increase, leading to increased nitrous oxide, particulate emissions and noise pollution, says Bitterlin.

“Diesel has the highest carbon emissions of all of the fossil fuels, other than brown-coal, so burning diesel to support the grid is not ‘clean’ in any way”
Ian Bitterlin, University of Leeds

“Diesel has the highest carbon emissions of all of the fossil fuels, other than brown-coal, so burning diesel to support the grid is not ‘clean’ in any way,” he says.

“The emissions from diesel generation meet all the international standards, but these only apply once the engine is running hot and loaded. Starting [one up] as fast as you can, as you would with a datacentre, produces high smoke and particulates, which often is a cause of complaint from neighbours.”

Given the pressure the datacentre industry is already coming under, from environmental lobbyists such as Greenpeace, to power their facilities with clean energy, operators should consider how users might view their decision to take part in such a scheme.

Dominic Ward, vice-president of corporate and business development at Iceland-based colocation provider Verne Global, says: “Sourcing clean, reliable, affordable electricity is critical to decision makers and CIOs, and there are only a small number of markets in the world that meet this combination of requirements.”

Changing perceptions

While there is plenty for the datacentre community to mull over when it comes to deciding whether or not to share their backup capacity, the fact of the matter is schemes – like the one British Gas is proposing – should not be needed, according to Bitterlin.

“We should have planned to grow our renewables, cut our coal and replace our nuclear power plants 20 years ago, not get ourselves into the position where our grid needs to burn oil in small, localised polluting installations instead of centralised efficient plants,” he says.

“Looking five or 10 years into the future, I think there is going to be a move towards more software-based redundancy and availability”
Andrew Donoghue, 451 Research

Even so, while there may be a degree of uncertainty and apprehension from operators about embracing new ways of working now, Donoghue believes the influence of the hyperscale cloud providers and their approach to datacentre operation may change that in the years to come.

“Looking five or 10 years into the future, I think there is going to be a move towards more software-based redundancy and availability. Putting more intelligence into the IT layer, instead of investing all of the main focus being on the physical infrastructure, such as generators, uninterruptible power supplies and other redundant components,” he says.

“That does feedback into things like demand response, because it means, if you have a less conservative attitude to physical redundancy, you might have more of an appetite for these kind of approaches in the future.”

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