Geothermal energy costs are modelled from first principles in this data-file. LCOEs of 6c/kWh are available in geothermal hotspots. Outside of the hotspots, enhanced geothermal heat can cost 2-14c/kWh-th for a 10% IRR on $500-5,000/kW-th capex, while a rule of thumb is that geothermal electricity costs 5x geothermal heat.
Geothermal energy is produced from 200 geothermal fields globally, feeding 16GW of power capacity, generating around 110 TWH of useful electricity, which equates to 0.4% of the world’s electricity and 0.15% of its total useful energy.
However this is almost all from geothermal hotspots (e.g., California, Indonesia, Philippines, Iceland), where hot fluids naturally well up to the surface. The levelized costs of geothermal electricity, in these hotspots, is 6c/kWh, as can be stress-tested in our model (chart below).
However, the average geothermal gradient globally is 25ºC per kilometer. Hence 100-300ºC temperatures are accessible by drilling deep wells, down to 3-10km total depth (chart below).
The pace of progress in enhanced geothermal has trebled in the past half-decade. This data-file contains a screen of over 20 enhanced geothermal pilots, tabulating their timings, total depth, bottom-hole temperatures, thermal capacity (in MW-th), electrical capacity (in MW-e), capex costs and other relevant details (chart below).
One factor that is hurting the economics of the geothermal power projects we have tabulated is that they are all small-scale pilots, with an average size of just 4MWe. We plot a line of best fit over the past data-points in the model. While it is always dangerous to extrapolate lines of best fit, we cannot resist doing this, as a simple ballparking exercise, to estimate where costs could end up at larger scale.
The levelized costs of enhanced geothermal are built up from first principles in the data-file, covering the costs of enhanced geothermal electricity, and enhanced geothermal heat. The capex costs for geothermal draw on our models, which capture the costs of drilling wells, heat exchangers and Organic Rankine Cycles.
Please download the data-file, to stress test geothermal energy costs, in hotspots (first tab), across geothermal electricity (second tab), geothermal heat (third tab), in other enhanced geothermal systems, and for other useful background data-points.