PDF ESTIMATION OF SOIL PERMEABILITY

FAQS about Energy storage field permeability calculation

Does permeability affect energy storage performance?

When permeability exceeds the critical value, energy storage performance worsens as permeability increases in the flat aquifer. However, when permeability is below the critical value, the energy storage performance remains almost unchanged. Fig. 4. Variation of energy efficiency and gas recovery ratio across different permeability values in CAESA.

What is the optimal permeability for energy storage?

An optimal permeability of 100md is identified for achieving the best energy storage performance. With a cyclic rate increase, the performance shows the opposite trends in different permeability regions and the optimum permeability becomes larger.

What is the optimal permeability?

The optimal permeability varies from 100 md to 300 md with the increasing cyclic rate due to the increasing competitive advantage of the deliverability. A large initial air bubble mass with sufficient air pressure support can improve the energy storage performance across all permeability cases.

How is relative permeability determined?

The relative permeabilities can be determined in various ways. If the local water saturation in Eq. (5) is known, the relative per-meabilities can be determined using one of the available relative permeability functions, f and g, of the water saturation as shown in Eqs. (8) and (9).

Why are relative permeabilities different from field data?

The reason for this difference can be that the relative permeabilities from the experimental data represent two phase flow in porous matrix rather than in fractured material as the relative permeabilities from the field data do.

How are relative permeabilities of water and steam calculated?

Relative permeabilities of water and steam were calculated, by applying the Shinohara method, using data from geothermal wells in Iceland. This method does not require that the local water saturation of the two phase mixture is known, but requires production history of mass flow and enthalpy from each well.