Using data centre waste heat to dry coffee whilst supplying small-scale farmers with ICT:a case study based on a novel systems-based approach

Terenius, Petter and Garraghan, Peter and Harper, R.H.R. (2020) Using data centre waste heat to dry coffee whilst supplying small-scale farmers with ICT:a case study based on a novel systems-based approach. In: 2020 International Conference on Sustainable Development, 2020-09-212020-09-22, Online.

Abstract

In light of the current climate crisis, a holistic approach to infrastructural matters regarding energy, communication, data and sustainable communities, as well as the water-food-energy nexus in general, is critical. One enabler for building sustainable communities around the Globe is ICT (information and communications technology). In the near future, the number of ICT systems will expand significantly in warm parts of the world, because of larger populations and increased relative wealth. As the backbone of ICT, data centres and mobile networks consume up to a few per cent of the world’s electrical energy, energy ending up as waste heat. In cold areas, the waste heat is sometimes reused to heat buildings. However, hitherto excessive heat has not been given much thought in regards to warm countries. In our research, we address waste heat from these systems, to reuse perhaps one or two per cent of the world’s future electrical energy. The relatively low outgoing temperature of a data centre’s airflow makes turning heat to electricity a non-viable option, as energy conversion losses would be massive. Hence, we focus on secondary uses for hot air. Based on a systems science approach, one of the themes we currently explore involves coffee drying. Many low- and mid-income countries are producing coffee, which needs drying as part of its production process. In some regions, coffee beans can be sun-dried, but other areas are too humid. In those cases, drying is commonly carried out using electricity-powered machinery. For a drying facility, the prospects of instead using waste heat to dry coffee are appealing. Conversely, if the presence of a drying facility in a community may be powered by waste heat, this may call for small-scale data centre construction, in turn increasing ICT availability locally or regionally. In other words, there is a bond between environmental gains and sustainable growth of a community. We are therefore investigating not only environmental but also societal benefits of this idea. For example, our approach gives more power to local producers of sustainable coffee: drying coffee beans close to source and then, through ICT, take a more active part in the supply chain may massively increase the profit for local farmers or collective efforts. Through a site selection based on a newly developed index, we have chosen Costa Rica for our case study, and arrived to an estimate for data centre waste heat drying capability in that country. We also discuss our findings in relation to the UN Sustainable Development Goals (SDGs). Due to the complexity of this project, it is too early to say to what extent data centre waste heat can indeed be used in these specific circumstances. Still, as coffee drying is achieved in different manners depending on topography, humidity, social structures, legislation and tradition, the innovative approach may have merit in some low- and mid-income country contexts.