For the design of the finned- plate LHTES system the afore presented simulation model is used. Apart from the
mere design, one of the objectives of the paper is to compare it with a conventional storage solution. Thus, the
design is constrained to provide approximately the same amount of storage capacity of 8.7 kWh. Moreover, a flow
rate of 5 l/min is imposed and a maximum duration for the charging/discharging process is set at 3 hours, which is a
common period for residential thermal solar or cogeneration installations. This information is used as input for a
parametric optimization , where the simulations are carried out sequentially by the FORTRAN programming
environment.
The simulations where made considering a 1 second times tep and a grid size of 1 cm in the x direction (as
validated in [16] ) . The nature of the simulation allows carrying out a high number of simulations at a low CPU cost.
Specifically more than 3000 simulations were carried out , using an AMD Turion Dual Core -Mobile 2.30 GHz with
6,00 GB RAM PC. Only a few hours were required to complete them. The optimal design for the imposed
constraints is presented in Table 3.