An interdisciplinary debate on project perspectives
Table 4 Wedge 3—subsoil heat extraction with a low-enthalpy geothermal system: assumptions.
Wedge 3. Footprint | ||
|---|---|---|
Probes sizing | ||
Construction | 2,320 | kWh/m |
24.378 | m3/m | |
Use | 1.747 | kWh/m |
0.472 | m3/m | |
Storage tank/boiler | ||
Construction | 4.18E−03 | kWh/m3 |
1.27E−01 | m3/m3 | |
Use | 4.00E−04 | kWh/m3 |
7.87E−03 | m3/m3 | |
Thermal needs | 10.00 | kW/m2 |
Geothermal power | 0.05 | kW/m2 |
Drilling depth | 120.00 | m |
Number of 4-pipe probes | 1 | Probe/250 m2 |
Storage tank/boiler | 2.50 | l/m2 |
Gross cost of the system | ||
Drilling | 90.00 | Eur/m probes |
Installation and cementation of the probes | 30.00 | Eur/m probes |
Heat pump | 45.00 | Eur/ m2 |
Storage tank/boiler | 0.35 | Eur/l |
Design | 7.50% | Net cost |
Works supervision, testing assistance | 5.00% | Net cost |
Testing | 2.20% | Net cost |
Safety charges not included in unit costs | 3.50% | Net cost |
Surveys, assessments, and investigations | 2.00% | Net cost |
Connection to the grid | 5.00% | Net cost |
Unforeseen costs | 5.00% | Net cost |
Average service life | 25 | Years |