Producing geothermal energy with a deep borehole heat exchanger: Exergy optimization of different applications and preliminary design criteria
| Autor: | Paolo Conti, Claudio Alimonti, Elena Soldo |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Exergy
deep borehole heat exchanger 020209 energy Borehole 02 engineering and technology Geothermal energy Industrial and Manufacturing Engineering geothermal energy exergy 020401 chemical engineering Heat exchanger ORC district heating absorption cooling plant 0202 electrical engineering electronic engineering information engineering 0204 chemical engineering Electrical and Electronic Engineering Process engineering Geothermal gradient Civil and Structural Engineering business.industry Mechanical Engineering Building and Construction Absorption cooling plant Deep borehole heat exchanger District heating Pollution Power (physics) General Energy Cascade Exergy efficiency Environmental science business |
| Zdroj: | Energy. 220:119679 |
| ISSN: | 0360-5442 |
| DOI: | 10.1016/j.energy.2020.119679 |
| Popis: | This paper aims at proposing fast and plain design tools to evaluate the best energy application for deep borehole heat exchangers, exploiting geothermal resources. Exergy efficiency has been chosen as a performance index. Five possible utilization solutions have been analyzed: district heating, adsorption cooling, ORC power production, a thermal cascade system, and combined heat and power configuration. An extensive sensitivity analysis on source characteristics and well geometry has been performed to find the design criteria that ensure the maximum exergy performance. Results show that configurations involving district heating are recommended for exclusive power production. If optimized, district heating exergy efficiency can reach values in the range 40%–50% when a geothermal source at the well bottom is lower than 300 °C. For higher values, the combined heat and power production is a preferable choice, reaching an exergy efficiency of up to 60%. Design charts are also provided to read first-attempt values of the well operative temperatures and flow rate to maximize exergy efficiency for each utilization layouts. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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