UPS innovation: Protecting critical loads and the national grid

Given increasing electricity consumption, data centres must evolve and implement new technologies to shift from being energy-guzzling resources to power reserves. It is crucial for the future that they play a more active role in supporting the power grid and being smarter in their energy usage.

In the last few years, the energy and balancing markets in various countries have started to open up – providing new opportunities for consumers and industry to participate in the market. Some data centres have already started tapping into these opportunities, using their back-up generators to participate and selling their capacity for frequency regulation to the grid.

As the energy market moves from fuel-based sources towards renewable energy, power production has the potential to become more volatile – making it harder to both predict and balance electrical supply. With the rise of renewables and increasing demand for electricity, it is also more likely that we’ll see fluctuating power quality in the grid. Data centre technology, specifically uninterruptible power supplies (UPS), can be used to tackle these issues.

Supporting grid capacity

In addition to back-up generators, UPS technology in a data centre or other commercial buildings can be leveraged to help energy providers maintain power quality by balancing power generation and consumption. The primary purpose of UPS technology is to protect the critical load by quickly providing emergency power when the input power source or mains power fails. Yet modern UPS technology is capable of much more.

As a secondary objective, dual-purpose UPS technology can support the power grid – a relatively new concept. The batteries can be discharged in parallel with the mains, with this power sharing seamlessly controlled. Additionally, a modern UPS can, when needed, feed power back to the grid, operating as a regenerative load. This flexible power management capability is unique and perfectly suited to providing grid support.

Balancing power fluctuation

With the correct control methods in place, UPS technology can rapidly respond to grid frequency variation requirements caused by disturbances in power generation. The higher penetration of renewables and modern industrial loads – and the resulting decrease in inertia in the power grid – means these frequency containment reserves against disturbances are becoming more crucial for grid operators. Traditional frequency regulation through hydro and gas turbines is facing challenges, given the need for swifter responses. As a result, we are seeing a need for new faster types of reserves, such as Firm Frequency Response. This is where power electronics and batteries can help.

UPS technology is also suitable for continuous frequency regulation – helping contain the mains frequency within normal limits during normal grid conditions. This requires the correct battery technology, suitable for the type of highly cyclic use where batteries are held in a partial state of charge.

Creating new revenue streams

Beyond supporting the grid, data centres can put investments to work by creating revenue streams from their UPS assets. To put it briefly, data centres can be compensated either for not drawing power, or for offering capacity back to the grid. By implementing UPS-as-a-Reserve (UPSaaR) technology, data centres can ensure they are in control of their energy – choosing how much capacity to offer back to the grid, when, and at what price.  

In this way, data centre operators can support the grid in frequency regulation while generating additional revenue to offset the total cost of ownership of the UPS or make the data centre more competitive on price. When developing the UPSaaR service in close collaboration with Fortum, a leading energy provider in the Nordic and Baltic countries, we demonstrated that data centres can work with a commercial energy aggregator to offer its capacity to the ‘national grid’ or Transmission System Operator, without any risks to the UPS’s primary function.

Smarter use of assets and resources is key if we want to reduce the increasing burden on the power grid. The right technologies exist and markets are opening up to create attractive business opportunities here. Implementing UPS technology to resolve power fluctuation and quality issues is now possible – and must happen sooner rather than later if we are to tackle these challenges.