Hydro Plants: When analysing the grounding performance of a large hydroelectric complex if one is to represent adequately the topological reality of the environment surrounding such installations, finite heterogeneous soil volume model becomes necessary. This soil structure model is made of a number of finite trapezoidal volumes having arbitrary resistivities different from that of the native soil.

Usually the Hydro plants are huge in size and to account for voltage attenuation along long conductors, recommended package for a Hydro plant is MultiGroundZ. However, if there are substantial reasons to believe that size of grid is small and soil resistivity is reasonably high, MultiGround package can be used.

Thermal Plants
Grounding study of a thermal plant can be easily done using MultiGround or MultiGroundZ packages. However sometimes, the rail track or fuel (coal) conveyance belts are required to be modeled. The above ground structures can only be modeled using Multifields but if the budget is a constraint, the conveyer belts or rail tracks can be modeled as if they exist underground. This provides a certain degree of approximation when fault levels are not very high.