Turning data centres green

15 September 2020

Vik Malyala, senior vice president, Supermicro

Vik Malyala, senior vice president, Supermicro

Imagine 350 tons – that’s three times the average weight of a blue whale and the amount of e-waste that could be saved annually by typical enterprise data centres. The energy that could be saved would even provide a big city with light.

Looking at the reality, only 12% of today’s data centres are green. A puzzling number, given that a sustainable approach would not only help the environment by reducing e-waste and consuming less power but also save data centre operators millions of pounds. With data centres playing such an essential role in our data-driven world, the challenge is to align their ecological footprint with sustainability targets.

Today, there are more than eight million data centres. Every year, they not only dispose of tons of hardware but they also account for about 1-1.5% of the global power consumption. This proportion is comparable with the level of carbon emissions of the airline industry around the world (before the pandemic). If the industry is not starting to take actions to reduce these numbers, chances are that in 10 years the energy consumption of data centres could make up more than 10% of the world’s electricity supply.

An increasing number of industry leaders and future-oriented companies already develop innovative solutions to approach this issue. However, there are still various missed opportunities when it comes to data centre efficiency. According to a 2019 green data centre survey undertaken by Supermicro, only 12% of today’s data centres are designed for optimal power consumption. This can cost operators of data centres up to 400,000 pounds per year, for example, due to older equipment. For 50% of survey respondents the success factors that are more closely associated with green data centres, such as Power Usage Efficiency (PUE) or IT Asset Lifecycles, aren’t taken into consideration as measurement, due to the focus for many being on ROI and TCO of the hardware alone without considering the data centre.

Today, data centres don’t have to be the “bad guys” in the green discussion anymore. Many businesses don’t seem to know all the options they have today. In the past couple of years, the industry has joined the green movement and created optimised server technologies, architectures for data centres and cooling techniques supporting this mission. They allow data centre operators to increase efficiency while reducing energy needs to a minimum. Some of the various technologies are better known than others.

One path towards greener data centres is the implementation of Resource Saving Architecture: it’s based on a disaggregated server design that allows individual components to be swapped out or upgraded independently. This eliminates expensive refresh cycles by focusing on upgrading what is needed to make the infrastructure optimized for their workloads, and improves PUE at the data centre level due to better thermal design.

In addition to the disaggregated server design approach, there’s also the option to increase the rack power density. Multi-node and Blade systems allow for more servers to be fitted into a smaller space thanks to their shared power supplies and fans (instead of rackmount servers with individual power supplies). It reduces the costs of cooling and can result in efficiency gains of up to 20%.

Dealing with data can work up a sweat – literally. While the average temperature of data centres lies around 23°C–24°C the survey has shown that more than a third of the data centres measure temperatures between 25°C and 29°C. With increasing temperatures rises the risk of overheating the servers which could cause performance degradation and impact user experience negatively. Plus, data centres thrive at colder temperatures. Thus, developing superior techniques to handle the heat - that are effective and sustainable - is crucial.

Free-air cooling is a common solution, whereby outside air is diverted inside the data centre requiring less air conditioner equipment in the server rooms. The energy savings can be significant, varying from 4-5% for every 0.56°C increase in server inlet temperatures. This can translate into savings of up to 12.000 pounds for the largest inlet temperature increase when looking at the annual OPEX savings per rack.

Alternatively, liquid-cooling is gaining popularity and reduces PUE immensely. Compared to more traditional air-cooling, it increases the processing per square foot and can reduce the OPEX by half. The latter due to the removal of provision power needed that would be necessary to keep the fans running.

Cooling and an increased rack power density are essential factors and a good starting point when it comes to optimising data centres from an energy perspective.

Companies must realise how big their impact is on the environment and that both sides benefit from more eco-friendly data centres. With 5G on the forefront and a growing number of IoT devices, it’s clear that our data consumption won’t reduce – rather the opposite. So, let’s make sure we manage a smooth transition towards a world with green data centres.

By Vik Malyala, senior vice president, Supermicro