Ehsan Nasr, Senior Engineer, Data Centre Advanced Development at Microsoft and Janne Paananen, Technology Manager at Eaton EMEA, spoke to DCR about how the humble UPS could help bring stabilisation and sustainability to the grid.
If the recent spate of hurricanes bombarding the US tells us anything, it’s that climate change is a problem we need to tackle in the here and now. Never has the adoption of sustainable energy been more important – and the energy-hungry data centre industry needs to be part of the solution.
At the beginning of September, Eaton and Microsoft released a whitepaper explaining how UPSs could be leveraged to both stabilise the grid and promote the adoption of more renewable energy sources.
DCR sat down with the two authors of the whitepaper, entitled Grid-interactive data centers: enabling decarbonisation and system stability, to find out a bit more about the technology behind the idea, and what it could mean for the future of the grid.
DCR: How did the whitepaper come about?
Janne: “Eaton has been working on this one for a few years, and we have been doing testing with grid operators and piloting in Europe. It was the natural next step, then, to make pilots with customers like Microsoft.
“The reason for writing the whitepaper is to clarify to the industry: What does it actually mean if you are using grid interactive UPS?
“It’s to bring some awareness to the market about the concept and the technology. To clarify some doubts, and try to create awareness and interest towards the technology, as both companies believe that this is the way to the future.”
DCR: Why is the UPS ideal for use in ancillary services for the grid?
Janne: “With the batteries connected to a UPS in a data centre, you get the stored energy that you need to provide the ancillary services. Then you also have the fast-switching power electronics that enable you to provide the fast and accurate response to the needs of the grid.
“If you leverage the capabilities of the hardware and you build the additional control layers, then it’s almost purpose-built to provide this type of service for the grid.
“If you compare the UPS, for example, to the large, grid-scale battery energy storage built for similar use for the grid – they are almost identical. They are made from the same components, same hardware, same technology and so on.
“You just need to bring similar functionalities into the UPS, and then you can start to leverage the existing assets, instead of building and investing more on separately dedicated assets, that would then increase the cost.”
DCR: Is there a lot of industry knowledge about this idea?
Ehsan: “Microsoft were assessing how to better utilise our existing assets to provide some services back to the grid – because traditionally, everything is just designed for the data centre. In this case, the UPS – and the battery inside of the UPS – is providing the backup application for the data centre.
“But with the new approach, we were thinking how we could innovate with our partners, like Eaton, to better utilise existing assets inside of the data centre, not only to provide the basic functionality as a backup, but also to provide extra services and provide more to the grid. Which is basically the transition from the UPS as only the backup to acting as a distributed energy resource.
“So in practice, the technology itself – that is not very new. But the application and the level of development happening is the new innovation.”
Janne: “From Eaton’s perspective, as the supplier of the equipment, we have also seen UPSs as underutilised assets, and knowing the capabilities of the technology, it could be done with the correct control algorithms.
“We can actually provide more value for the product itself and for the existing assets and use those more smartly.”
DCR: How can data centre operators be sure the UPS will always be available for the data centre’s needs?
Janne: “The job of the UPS is to secure the critical load – and you can never jeopardise that. Whenever you talk about this type of concept, people start to have their doubts about risking the load – but it’s actually quite easy to use certain methods to make sure that you don’t. So you’re going to always reserve enough energy in the back that is for the critical load.
“If you have an abnormal situation, the UPS reverses to its basic operation and stops the additional things.
“So when you know what you are doing, you have the experience of the UPS design and you know what the priority is, then you can mitigate your risks.”
Ehsan: “One of the key aspects for data centre operation is ensuring the complete integration of the new technology into the existing traditional UPS system that we use for backup. And that’s why we are using the pilot project, to make sure there is no impact or any risk on the load.”
DCR: What’s the impact going to be in terms of maintenance and replacement for the UPS?
Janne: “It depends on the market. But, especially if you are aiming for things like fast frequency response that is providing support for the grid during low inertia and against the larger disturbances, the amount of activations and the additional use on the UPS is marginal.
“But of course, like in every case, the UPS needs to have annual maintenance and you need to follow how things are working. And maybe in some other markets, where the use of the UPS would be more continuous – it’s not really a problem for the UPS itself, but you need to have a closer look at the batteries.
“But that’s why we are collecting data and monitoring – the equipment is under continuous supervision, so there’s no problem.”
DCR: Do you think it will be a struggle to incorporate more renewable energy into the grid, and to make it reliable enough for use, without these sort of innovations?
Janne: “There are a couple of challenges relating to renewable energy and the most obvious one is the intermittent nature of the production of renewable energy.
“And for that, one, you need to have more long-term balancing reserve systems – bigger power plants, or bigger energy storages, like pumped hydro and so on.
“Then the other, not so often discussed, challenge is the impact to inertia from renewable energy with non-synchronous generation. When the inertia is reduced on the power grid, then the system becomes more vulnerable against large disturbances, and you’re going to have much bigger and faster frequency variations. And worst case, you need to shut down parts of the grid or the complete grid goes down – like what happened in the UK in August a couple of years ago. So that’s the major concern.
“So when the amount of renewables goes up, and especially in the smaller, synchronous areas, like Texas or the UK, Ireland, the Nordics, Australia, New Zealand – in those grids, you need to have some form of fast response to contain the frequency.
“And then the question is, from where do you get this fast response? Do you need to separately build a large battery and storage system to do it? Or can you leverage existing assets? And we believe that leveraging the existing assets to provide the services for the grid is the correct way of doing it. You reduce the cost, you use the resources more smartly and you also reduce the need for additional investments and use of natural resources.
“So there’s a need for the technology.”
Ehsan: “From a data centre aspect, for every megawatt of the IT load that we build, we need to have one megawatt of backup. And we do have a one megawatt of energy storage or battery inside of the UPS. Typically, we have a power plant or a battery plant close to the data centre, because of the need that we have for a backup.
“So it means that there’s a significant opportunity inside of the data centre, because we already have all of those batteries and the generation asset inside of the data centre, because that is the design for a backup.
“At Microsoft, we see this as a huge opportunity if we can use our existing assets to provide the functionality that we need, for example, for frequency regulation, or other applications like bill management or load shifting.
“This is a huge opportunity that can address some of the challenges that the grid has.”