The economic model uses a number of parameters. The assumption is that the investment must be earned back in fifteen years. This is also the duration of the SDE+ scheme (Stimulation of Sustainable Energy Production).
The CAPEX consists of well costs and other (installation) costs. The well costs are depth dependent. They are calculated as:
Well CAPEX = 375000 + 1150 x depth + 0.3 x depth² [€]
The OPEX is partially dependent of the produced power and partially dependent of the amount of produced energy (heat). Apart from this, the electricity cost for running the pump is calculated. Using a discounted cash flow model, the cost price per unit of energy is calculated [€ct/kWh].
Next, the economic potential is calculated by comparing the cost price with a reference price. The reference price is 5.1 €ct/kWh, which corresponds to the SDE+ amount for geothermal energy. For doublets deeper than 4,000 m another SDE+ category is valid, which uses a reference price of 6.5 €ct/kWh. For the maps shown in the Map viewer, the following classes are defined:
- Unknown: P10 cost price > reference price
- Indication: P10 cost price < reference price
- Moderate: P30 cost price < reference price
- Good: P50 cost price < reference price