The dataset of optimal designs of the Waste2GridS plant was used in Figure 6 of the publication: Ligang Wang, Yumeng Zhang, Chengzhou Li, Mar Pérez-Fortes, Tzu-En Lin, François Maréchal, Jan Van herle, Yongping Yang. Triple-mode grid-balancing plants via biomass gasification and reversible solid-oxide cell stack: Concept and thermodynamic performance. Applied Energy (280), 2020, 115987. The dataset includes all information on the optimal plant designs with respect to the six technology combinations and three objective functions. With these data, it is easy to create the mass and energy balance of each plant design and to enable a closer look at each design.