Doublet and economic parameters in geothermal calculations
The two tables below list the technical and economic parameters that are used in the calculations. The Calculation model section provides a more detailed explanation of these parameters and also of the depth-dependent and optimized parameters.
| Technical parameters | Value | Unit |
|---|---|---|
| aquifer top depth | from map | m |
| aquifer thickness | from map | m |
| aquifer thickness uncertainty (SD) | from map | m |
| aquifer net-to-gross | from map | - |
| aquifer permeability | from map | mDarcy |
| uncertainty in natural logarithm permeability | from map | ln(mDarcy) |
| aquifer temperature | from 3D model | °C |
| aquifer water salinity | depth dependent | ppm |
| aquifer kh/kv ratio | 3 | - |
| return temperature | 30 | °C |
| minimum aquifer temperature | 20 | °C |
| distance between the two wells | optimized | m |
| pump system efficiency | 60 | % |
| production pump depth | 500 | m |
| pump pressure difference | optimized | bar |
| well trajectory curvature factor | 1.1 | - |
| calculation segment length | 50 | m |
| outer diameter (open production interval) | 8.5 | inch |
| inner diameter (casing) | 8.5 | inch |
| casing roughness | 1.38 | milli-inch |
| injector well skin | -1 | - |
| production well skin | -1 | - |
| Economic parameters | Value | Unit |
|---|---|---|
| economic lifetime | 30 | year |
| drilling time | 2 | year |
| annual load hours | 6000 | hour |
| well costs | depth dependent | M€ |
| CAPEX base expense (excl. wells) | 3,5 | M€ |
| CAPEX variable expenses (excl. wells) | 882 | €/kW |
| CAPEX contingency | 0 | % |
| annual OPEX per unit power | 81 | €/kW |
| annual OPEX per unit energy produced | 0.062 | €ct/kWh |
| electricity purchase price for operations | 23 | €ct/kWh |
| tax rate | 25 | % |
| interest on loan | 5 | % |
| inflation | 1.5 | % |
| required return on equity | 14.5 | % |
| debt ratio | 80 | % |