Sustainability is therefore as much on their minds as those of the legislators for ensuring energy efficient and carbon-free operation of existing facilities. Equally, to secure the permits and planning permissions necessary for delivering data centres in new locations.
Using renewable energy and leveraging on-site power generation are key factors including solar, wind, biogas and hydrogen. However, looking to the future, the implementation of innovative sustainable solutions in collaboration with the local community is also a priority. nLighten terms this “sector coupling” which is not a new term in the energy sector but one which has excluded data centres until recently.
Sector Coupling
This is the practice of energy recovery and reuse between producers and users of energy to affect lower aggregate emissions and a higher overall efficiency. It is no longer the data centre in isolation: the new definition of data centre operations takes the community infrastructure into account and redefines the data centre as a lever to environmental improvement.
After all, in our digital economy we are now as dependent on data as we are on established industrial utilities such as power, water, heating or cooling. The energy transition and increasing trend toward weather dependent generation makes the energy sector dependent on energy storage and recovery. Yes, our utilities are all in a state of change to protect the environment and data centres are a part of this as a significant energy user.
Heat Exchange & Re-Use
Heat recovery and re-use as a by-product of data centre operations provides an emission free source of heat, which often offsets carbon rich energy sources for heating such as oil or natural gas. Northern Europe, for example, has significant potential for heat re-use with the growing demand for regional edge data centres. Increasingly, these are being strategically located close to end users and therefore ideally positioned to export excess heat.
Renewable power sources therefore offer the potential to substantially reduce emissions while supporting power and heat sharing with local utilities. Having more data centres closer to urban areas will significantly facilitate local recovery and export of heat energy to the community.
The latest generation of cooling systems have the ability to seamlessly upgrade heat exported from data centres and create a carbon free heat source to assist district heating systems. New cooling solutions for higher power densities additionally assist heat recovery efficiency via their higher operating temperatures, while removing the need for evaporative cooling, conserving water usage in the local community.
In 2023, for example, the City of Eschborn and the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH in Germany signed an agreement with nLighten for heat exported from its edge data centre at high temperatures. The recovered heat will warm the public swimming pool complex and several city buildings, contributing positively to the local energy infrastructure.
Grid Stabilisation
Ongoing energy transition requires an increasing amount of renewable power generation which is often weather-dependent. This results in a variable grid capacity and regular mismatches between the supply and demand of power in the system – in particular the constant data centre load profile is increasingly incompatible with the renewable targets of the utility sector. For example, in countries such as Norway and Sweden, weather conditions can greatly impact hydropower generation. During dry periods, production can decrease, leading to a reduction in grid capacity and potential energy shortages.
The solution is the deployment of grid balancing systems. These can use energy storage systems and onsite generation at the data centre to support capacity and create a varied load profile that is more compatible with renewable generation. The increasing capacity of data centre power systems offers enormous potential to reduce grid dependence on fossil fuel power plants during periods of frequency deviation.
Using carbon neutral on-site generation and energy storage, nLighten’s ambition is to evolve our data centres such that they support utilities in their energy transition. This can create a synergy between the growth of data centres for the digital economy and emissions reduction in community infrastructure.
