According to the latest statistics from the International Energy Agency, data centres and data transmission networks each account for around 1% of the world’s electricity demand – that equates to an estimated 200 terawatt hours (TWh) of power every year.

In fact, despite more servers being added annually, data centres have managed to keep their collective power demand consistently around 2% since 2005, but how long this can be sustained remains to be seen.

In 2020, the world generated 40 ZB of data and this is estimated to grow to 180 ZB by 2025. In the face of such exponential growth, operators need to find new and innovative ways to expand their facilities without raising carbon emissions or taking large amounts of energy out of the grid.

One way to do this is through diligent UPS specification and operation. While UPS provides essential protection against power failures, voltage regulation, power factor correction and harmonics, it must be clean and energy efficient to help data centre operators manage their daily energy use and emissions – and even more so as they rush to add extra capacity.

Choosing cleaner, greener technology

With modern technology, there are now better options for power protection in medium voltage (MV) applications (compared to rotary UPS). New MV UPS solutions provide a valid alternative for low voltage (LV) UPS in applications where centralised critical power systems are preferred. This was not the case in the past, where the benefits of modern static UPS were superior to MV-side alternatives.

Now, data centre builders can choose the system that best meets their needs. As data centres continue to grow in terms of size, configuring UPS protection at the MV level offers an energy-efficient and environmentally friendly alternative and it will gain more and more popularity.

Both LV and MV UPS technology is advancing all the time, and we are now seeing new models hitting the market which increase energy efficiency significantly – this year, we’ve seen an MV UPS solution come to market that offers 98% efficiency, which would have been unheard of a few years ago.

One reason that higher efficiencies are possible is that the design of UPS systems is moving away from traditional diesel rotary systems and adopting more innovative static converter architecture. When comparing the two types of UPS, a static converter-based system can deliver substantial energy savings when compared to a rotary system during its lifespan.

Another consideration should be your UPS’ back-up power systems. The most common back-ups are diesel and slow-paced gas generators – which both add to a data centre’s carbon emissions – and turbines. In the future, back-up power could be provided by alternative, low or zero carbon energy sources such as hydrogen. Although we are a little way off the infrastructure to make that a reality, it is worth considering the specification of UPS which can be adapted to work with alternative energies in the future.

Furthermore, LV and MV static UPSs can protect the load against grid events, providing clean and reliable power in accordance with IEC62040-3 class 1 and ITIC requirements.

Giving back to the grid

Data centres have large static demands, which can put pressure on national power grid operations. But with some advanced UPS systems, data centres can be used to give back to the grid, rather than just taking power out of it.

As electricity grids transform to use more renewable energy resources, they need to find new ways to balance and stabilise the system to meet peaks and troughs in demand. These balancing services used to be provided by coal and gas fired power stations, but unfortunately electricity system operators can’t switch wind and solar generation on and off when they need to! So other ways to balance the grid are needed.

UPS can be fitted with Frequency Regulation Functionality (FRF) which allows the power grid to tap into a data centre’s unused reserves of power to respond to varying load demands and to maintain the grid’s frequency levels. Severe frequency deviations can cause power blackouts, so by helping the grid operator, a data centre also help resolve issues which would affect their own operations.

The way it works is simple. Normally, energy flows from the grid to the load and the battery, to keep it charged. If there is a grid issue (for example if the grid is under pressure to deliver more electricity during a peak period), energy for the load is taken from the data centre’s UPS battery.

This support can also go the other way. If there is an increase of grid frequency and the grid operator needs to offload some power, it can be discharged to the UPS battery banks.

As well as helping to balance the local power grid, adding FRF to UPS installations helps balance the books. Grid operators offer financial compensation for frequency balancing services, so data centres can effectively use their UPS equipment as a revenue generation asset, turning previously depreciating capital into a new revenue stream, while meeting corporate sustainability targets.

The future is green

With careful specification and diligent operation, UPS can deliver reliable, clean power for mission critical infrastructure, giving data centres a way of reducing their energy usage and carbon emissions without compromising on the integrity of their operations.

By supporting the shift to renewable energy generation and helping to reduce CO2 emissions on a national level, incorporating FRF can have a positive environmental impact. It introduces data centres to an effortless way to contribute to a greener world while putting the energy supplier and consumer ahead of the game when it comes to new emissions standards.