Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction
Abstract
Conventional concentrated solar power (CSP) is a reliable alternative energy source that uses the sun’s heat to drive a heat engine to produce electrical power. An advantage of CSP is its ability to store thermal energy for use during off-sun hours which is typically done by storing sensible heat in molten salts. Alternatively, thermal energy may be stored as latent heat in a phase-change material (PCM), which stores large quantities of thermal energy in an isothermal process. On-sun, the PCM melts, storing energy. Off-sun, the latent heat is extracted to produce dispatchable electrical power. Here, this paper presents the design of a thermosyphon-based device with sodium working fluid that is able to extract heat from a source as demand requires. A prototype has been designed to transfer 37 kW of thermal energy from a 600°C molten PCM tank to an array of 9% efficient thermoelectric generators (TEGs) to produce 3 kW of usable electrical energy for 5 h. This “thermal valve” design incorporates a funnel to collect condensate and a central shut-off valve to control condensate gravity return to the evaporator. Three circumferential tubes allow vapour transport up to the condenser. Pressure and a thermal resistance models were developed tomore »
- Authors:
-
- Colorado School of Mines, Golden, CO (United States). Physics Department
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Bucknell University, Lewisburg, PA (United States). Mechanical Engineering Department
- Colorado School of Mines, Golden, CO (United States). Physics Department; National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Publication Date:
- Research Org.:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Sponsoring Org.:
- USDOE Advanced Research Projects Agency - Energy (ARPA-E)
- OSTI Identifier:
- 1393371
- Alternate Identifier(s):
- OSTI ID: 1550598
- Report Number(s):
- NREL/JA-5500-67912
Journal ID: ISSN 1359-4311
- Grant/Contract Number:
- AC36-08GO28308; AR06704918
- Resource Type:
- Journal Article: Accepted Manuscript
- Journal Name:
- Applied Thermal Engineering
- Additional Journal Information:
- Journal Volume: 126; Journal Issue: C; Journal ID: ISSN 1359-4311
- Publisher:
- Elsevier
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 14 SOLAR ENERGY; 47 OTHER INSTRUMENTATION; PCM; sodium; thermal valve; thermosyphon; CSP; heat pipe
Citation Formats
Oshman, Christopher, Hardin, Corey, Rea, Jonathan, Olsen, Michele L., Siegel, Nathan, Glatzmaier, Gregory C., Parilla, Philip A., Ginley, David S., and Toberer, Eric S. Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction. United States: N. p., 2017.
Web. doi:10.1016/j.applthermaleng.2017.01.038.
Oshman, Christopher, Hardin, Corey, Rea, Jonathan, Olsen, Michele L., Siegel, Nathan, Glatzmaier, Gregory C., Parilla, Philip A., Ginley, David S., & Toberer, Eric S. Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction. United States. https://doi.org/10.1016/j.applthermaleng.2017.01.038
Oshman, Christopher, Hardin, Corey, Rea, Jonathan, Olsen, Michele L., Siegel, Nathan, Glatzmaier, Gregory C., Parilla, Philip A., Ginley, David S., and Toberer, Eric S. 2017.
"Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction". United States. https://doi.org/10.1016/j.applthermaleng.2017.01.038. https://www.osti.gov/servlets/purl/1393371.
@article{osti_1393371,
title = {Design of a thermosyphon-based thermal valve for controlled high-temperature heat extraction},
author = {Oshman, Christopher and Hardin, Corey and Rea, Jonathan and Olsen, Michele L. and Siegel, Nathan and Glatzmaier, Gregory C. and Parilla, Philip A. and Ginley, David S. and Toberer, Eric S.},
abstractNote = {Conventional concentrated solar power (CSP) is a reliable alternative energy source that uses the sun’s heat to drive a heat engine to produce electrical power. An advantage of CSP is its ability to store thermal energy for use during off-sun hours which is typically done by storing sensible heat in molten salts. Alternatively, thermal energy may be stored as latent heat in a phase-change material (PCM), which stores large quantities of thermal energy in an isothermal process. On-sun, the PCM melts, storing energy. Off-sun, the latent heat is extracted to produce dispatchable electrical power. Here, this paper presents the design of a thermosyphon-based device with sodium working fluid that is able to extract heat from a source as demand requires. A prototype has been designed to transfer 37 kW of thermal energy from a 600°C molten PCM tank to an array of 9% efficient thermoelectric generators (TEGs) to produce 3 kW of usable electrical energy for 5 h. This “thermal valve” design incorporates a funnel to collect condensate and a central shut-off valve to control condensate gravity return to the evaporator. Three circumferential tubes allow vapour transport up to the condenser. Pressure and a thermal resistance models were developed to predict the performance of the thermal valve. The pressure model predicts that the thermal valve will function as designed. The thermal resistance model predicts a 5500× difference in total thermal resistance between “on” and “off” states. The evaporator and condenser walls comprise 96% of the “on” thermal resistance, while the small parasitic heat transfer in the “off” state is primarily (77%) due to radiation losses. Lastly, this simple and effective technology can have a strong impact on the feasibility, scalability, and dispatchability of CSP latent storage. In addition, other industrial and commercial applications can benefit from this thermal valve concept.},
doi = {10.1016/j.applthermaleng.2017.01.038},
url = {https://www.osti.gov/biblio/1393371},
journal = {Applied Thermal Engineering},
issn = {1359-4311},
number = C,
volume = 126,
place = {United States},
year = {Mon Jan 16 00:00:00 EST 2017},
month = {Mon Jan 16 00:00:00 EST 2017}
}
Web of Science