| Title | Economic Comparison of Seasonal Heat-Storage in Combination with a Deep Geothermal Doublet with Two Doublets, Example from the Pilot Project in Bern, Switzerland |
|---|---|
| Authors | Dieter Ollinger, Peter Meier, Florentin Ladner, Martin Jutzeler and Urs Spring |
| Year | 2018 |
| Conference | Asian Geothermal Symposium |
| Keywords | Seasonal heat-storage, sandstone layers, economic analysis, combination of geothermal heat production from deep wells and heat storage in shallow formations |
| Abstract | In climate zones with hot summers and cold winters and with geothermal gradients (<= 35°C/km) requiring to drill deep wells (> 3000 m) for district heating at 90-110 °C it may be economically advantageous to construct one well doublet (> 3000 m) together with a seasonal underground heat storage at shallow depth of around 500 m and to operate the system also during summer, instead of constructing two well doublets which operate only in cold months of the year. Of course, such a concept relies on good hydrogeological conditions in the lower deep geothermal reservoir and in the upper storage reservoir. We present the concept and the plans for a pilot project in the city of Bern, being part of HEAT-STORE GEOTHERMICA. |