Standby Power Supply For Increased Risk of Outages

Colin O’Neill from standby power specialist, Dieselec Thistle, explains the implications of the Ofgem Electrical Capacity Report for the data centre sector and advises on how operators need to have a robust energy strategy in place to mitigate an increasing risk of outages 

An effective and reliable standby power supply has always been business critical in the data centre sector.  Loss of power for any reason has the potential to damage expensive equipment, knock out cooling and filtration systems and, most importantly, cause loss of data.  Even temporary problems that make data unavailable for a matter of hours could potentially cause loss of reputation and future business to both data centre operators and their clients, pushing the standby power installations that underpin business continuity up the priority list.

Last October, Ofgem, at the Government’s request, published its first ‘Electrical Capacity Report’; a document that will become an annual assessment of the National Grid’s capacity and the risk of outages.  The next report is due in September and, while we must wait until then to find out whether there have been any changes to Ofgem’s predications last year, it is unlikely that the level of risk will be downgraded… fact it seems likely to be the reverse.

Sobering Discussion

While many of the alarmist headlines when the report was first published plundered the document for some of the more extreme predictions and covered them out of context, the fact remains that the report was an uncomfortable read for most. Uncomfortable for the Government as it clearly highlighted the need for a coherent strategy that could be delivered swiftly to avoid the risk for outages.  Uncomfortable for business critical commercial energy users like data centres because it highlighted that risk of outages is set to increase significantly over the next three years.

At the heart of the problem is a very simple equation:

Increased energy demand + decreased generating capacity = shortfall of electricity

The reasons why the UK has reached a point where that equation is inevitable are more complex. There has been a concerted effort to reduce the energy consumption of individuals, organisations and UK Plc over the past few years which is all very positive….but it has only served to reduce the pace of the growth in energy demand. Better buildings, better energy efficiency behaviours and more energy efficient appliances and equipment cannot prevent growth in demand from an increasingly large, increasingly technology dependant population. As a result, demand on the grid continues to grow and, thanks to some very harsh winters in recent years, at certain points in the calendar spikes in demand have also been noticeable.

Meanwhile, the same emphasis on reducing the nation’s carbon footprint that has helped us control if not halt the growth in energy demand is also reducing our generating capacity.  Carbon reduction targets have led to the phase out of coal-fired power stations, which are being decommissioned and replaced by cleaner technologies.  The problem is that the cleaner generation methods are not coming on stream as fast as the old power stations are being de-commissioned and, as yet, there is no coherent plan in place to replace all the generating capacity we’re losing.  What’s more, even if the Government were to give the green light to major energy projects tomorrow – whether they be wind farms or nuclear power stations – there would not be time for them to have a positive impact on the level of supply available from the National Grid before we lose the capacity of our coal-fired power stations.


Data Centre Implications

All of this is creating the perfect storm, which the Ofgem report predicts will come to a head during the winter of 2015-2016, particularly if that winter happens to be as cold as those we’ve experienced in recent years. At that point, the National Grid will be at its most vulnerable in terms of both the level of demand and the supply capacity, presenting a risk of regular outages.  The report places a wide spectrum of risk on its predictions of outages, ranging from a worst case scenario of a 50% risk to a more modest best case of a one in twelve chance.  Either way, these are worrying figures for the data centre sector where any loss of power could mean loss of data and damage to hardware.

Even more worrying to the commercial world is the report’s discussion of the potential solutions that the Government could put in place to protect continuity of supply to domestic dwellings and essential services such as hospitals and schools. The report discusses the possibility of ‘controlled disconnections’ whereby electricity supplies are managed by disconnecting commercial users at certain times for specified periods to minimise the risk of outages. While many types of businesses could adapt to such a regime if it had to be introduced, it would be catastrophic for the data centre sector.

It seems unlikely that the Government would take such an extreme course of action but the very fact that it is raised as a possibility in the report demonstrates the seriousness of the energy supply and demand problem. It should be clear to all data centre operators that, whether the worst or best case scenario prediction turns out to be closest to the truth, the sector needs to be ready for outages and has only a limited time to ensure the required standby infrastructure is in place.


Suitable Standby

It should be safe to assume that all data facilities, large or small, have some kind of standby power provision, so the question in light of the Ofgem Electricity Capacity Report should not be ‘do you have a standby power system?’, but ‘is your standby system sufficient?’.

The increased risk of outages and the likelihood that they will become more regular means that data centre operators must ensure that their standby provision has sufficient capacity for the entire load required at their facility for prolonged periods of time.  While a standby-rated installation will provide up to 20 hours of emergency power, a prime-rated installation can operate indefinitely, providing a continuous alternative power supply (assuming the proper fuel and maintenance requirements are in place).

As data centres are scaled up, it is essential that their standby power provision keeps pace with the power consumption levels of the whole facility.  Maximum required load should be fully assessed and any specified system should be thoroughly load tested prior to installation to ensure that the standby system’s power output is aligned to the data centre’s actual need. Specifying an appropriate system may not only mean increasing the amount of generator plant installed but may also involve enhancing the control systems that are required to achieve a no-break automated start up, load-sharing between generators and prioritisation of business critical systems. Without a robust and appropriate system, even data centres that have their power supplies protected by standby generators could find themselves vulnerable if frequent and sustained outages start to happen, so a tailored control system designed by standby power experts with experience in the data centre sector has a critical role to play in ensuring that the installation can respond quickly and effectively to any eventuality.

In addition to the standby plant and controls, fuel supply and maintenance are also essential considerations for data centre operators when gearing up to mitigate the increased risk of outages. A prime-rated standby power installation is designed to operate indefinitely in the event of a mains failure but it can only operate for as long as there is a fuel supply available.  As a result, the fuel infrastructure may also need to be upgraded and fuel needs to be managed, not only in terms of availability but also in terms of quality. The reformulation of diesel to include a proportion of biofuel means that fuel stored for prolonged periods may spoil, so ensuring that the available fuel is fit for purpose at all times is critical to the standby power installation’s effectiveness.  Similarly, maintenance must take on even greater importance to ensure that the standby plant is always available.  Dieselec Thistle has already established a dedicated division to cater for increased demand for maintenance contracts in the data centre sector and predictive maintenance and regular testing of the standby power provision is recommended. Fault recognition can also be built into the control system to ensure that potential triggers for system failure can be flagged and addressed before a problem arises.


Be Prepared

The UK has had to manage through times of energy shortages before and the pace of development in terms of renewable technologies is accelerating thanks to energy company investment and carbon reduction targets so our generating capacity should increase again over time.  However, though only three decades ago, previous energy shortages were in a different age before the data centre sector existed and before the UK was so energy hungry both at home and at work.

There is no need to panic and we should all be wary of scaremongering, however, all businesses should ensure they identify risk and take steps to address it.  In the data centre sector, the risk of power outages will be higher over the next few years than it has ever been and operators must ensure that they have reliable standby power solutions in place to underpin business continuity