Is Hot IT a False Economy?

Understanding the impact of data centres and the efficiency of IT hardware is central to the work that we do at Techbuyer – we work to create high-performance, yet highly efficient devices for our customers on a daily basis. However, our research team are continuously working to deepen our understanding of data centre best practice and efficiency to explore how we can best service our clients.  

This month, our research team have had their work, exploring the impact of hot IT across an entire data centre’s environment, published within the IEEE Transaction on Sustainable Computing peer-reviewed journal.  

This paper examines and releases findings on the current data centre trend of hot IT, asking the question: does reducing the cooling of your data centre save money?  

What is Hot IT?  

Hot IT is a process of reducing the external cooling of a server, or entire data centre, to reduce running costs and, in theory, increase the energy efficiency of the facility.  
Data centres measure efficiency in terms of PUE, meaning that, in order to be deemed efficient, the facility must direct as much of their energy consumption towards the IT hardware. This means that, reducing the cooling of the data centre, according to PUE, makes the data centre more energy efficient as they are reducing the energy that they expand outside of the IT hardware itself.  

But what does this achieve in practice?  

The Effects of Hot IT on Hardware 

Within this study our research team ran different server models at different temperatures to explore the effect of hot IT on the device. Within every case, the hotter the environment in which a data centre is housed, the more inefficient the device became. This is because the fans within the device need to work harder to dispel more of the generated heat and keep the server cooler. 

However, we also observed an increase in leakage current as the server became hotter. This means that the server was working harder, and expending more energy, in order to perform the same tasks.  

For a singular device, the increase in energy consumption is measurable, yet not drastic. However, how does this change if we apply this to an entire data centre?  

Data Centre Performance in the Face of Increased Temperature 

Using software from Green Grid, we developed a digital data centre based off the makes and models of servers that we were testing and transplanted this data centre into different conditions and countries around the world to observe the effects on performance and efficiency.  

In terms of hot IT, we observed a digital data centre based in London, running the same tests as outlined above.  

What we observed was that, if you cooled less but, as a result, increase the air temperature of the data centre, you negate some, or in some cases all, of the savings that you would expect to see. You also run the risk of a higher failure rate and decreased lifespan of components and devices.  

Data centres that used water chillers, rather than direct expansion (traditional air conditioning), still performed at a net positive, however, the amount of saving depends on model, age, condition of servers and location.  

What This Means 

When making changes throughout your data centre, it is important not to make decisions in isolation – adjustments that impact multiple systems will have unforeseen consequences, and efficiency is about balancing these consequences to create a net positive.  

Techbuyer is a leading specialist in sustainable IT solutions with a dedicated research team working to deepen our understanding of hardware through front-line research. We use this research to inform the solutions we supply to our customers, including server design, infrastructure consultancy and performance analysis. Find out more about everything that we can offer here.