How to build green substations? An LCA comparison of different sustainable design strategies for substations

Abstract The growing industry of Information and Communication technology necessitates an increase in the construction of data centers and substations that supply them with electricity at high voltage levels. The increase in the construction of data centers and therefore substations on the one hand, and their high energy consumption on the other hand, makes sustainable substation design of utmost importance to prevent environmental degradation. However, current studies often consider only the operation phase of the building and neglect other life cycle stages, resulting in biased decisions that shift the environmental problems from one stage to another that were not included in the scope of these studies. This paper investigates Life Cycle Assessment (LCA) of a typical substation located in Germany, and applies three sustainable design strategies by creating scenarios, each varying in building material composition, waste heat utilization from data centers, and incorporation of green electricity from the grid. The environmental performance of these scenarios was evaluated using the One-Click LCA. Results indicate that switching to green electricity is the most impactful strategy that reduces the Global Warming Potential (GWP) to approximately 33 % compared to the base case. In the best solution which mixed all strategies, sharp reduction of GWP to 17.5 % was achieved. The highest impactful element of the building was its structure where the major building weight and a considerable amount of concrete cause the most GWP. Furthermore, the choice of materials is mainly important because of their embodied emissions, rather than their energetic values.