3.2. Impact of tower design on tower storage
To calculate the potential energy storage capability in the tower volume of a wind turbine, the NREL 5 MW baseline is modified to include the hydraulic-electric design integrated with a novel isothermal CAES as shown in Fig. 1c (and described in Refs. [7] and [8]). For the hydraulic-electric/CAES combination, the open accumulator concept has been shown to be compatible for this combination [18], and its compressed air energy density (Eη) can be computed as