Off-grid solar thermal water heating system using phase-change materials: design, integration and real environment investigation

Jyoti Prakash, Daryn Roan, Wajeha Tauqir, Hassan Nazir, Majid Ali, Arunachala Mada Kannan

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

A solar thermal water heating system using a custom-built latent heat storage tank with paraffin wax, puretemp68 and stearic acid/palmitic acid eutectic mixture based phase-change materials was designed, developed and its performance evaluated in real-time. The fully autonomous off-grid solar thermal water heating system was packaged by integrating solar thermal collector, phase change material tank, photovoltaic modules, operational controller, circulation pumps and battery, along with a data logger. A water-glycol with anti-freeze characteristics with efficient energy storage in cold weather was employed as heat transfer fluid for solar thermal energy harvesting for charging and discharging of phase change materials to heat the water tank. Solar charge-discharge and water charging results with phase change materials during May to October 2018 (Mesa, AZ 85212, USA) showed that the stearic acid/palmitic acid eutectic mixture outperformed the paraffin wax and exhibited comparable performance with puretemp68 storage system. The efficiency of water charging from stearic acid/palmitic acid (55%) is higher compared to that from paraffin wax (20%) and better than puretemp68 (45%). Even though, the paraffin wax melts quickly during charging, it exhibited super-cooling behavior during discharging, leading to incomplete discharge. The storage energy density of stearic acid/palmitic acid (∼0.48 MJ kg −1 ) is comparable to puretemp68 with uniform thermal energy distribution inside the storage container due to higher thermal conductivity and lower melting point. The solar thermal water heating system demonstration proved that the domestic hot water system using stearic acid/palmitic acid could be a practical solution for effectively harvesting solar thermal energy for rural areas.

Original languageEnglish (US)
Pages (from-to)73-83
Number of pages11
JournalApplied Energy
DOIs
StatePublished - Apr 15 2019

Fingerprint

Phase change materials
thermal water
Palmitic acid
Stearic acid
Paraffin waxes
heating
Heating
acid
Thermal energy
Water
wax
Energy storage
Eutectics
Water tanks
Heat storage
Energy harvesting
Latent heat
Hot Temperature
material
Glycols

Keywords

  • Latent heat
  • Off-grid system
  • Phase change material
  • Solar thermal water heating

ASJC Scopus subject areas

  • Building and Construction
  • Energy(all)
  • Mechanical Engineering
  • Management, Monitoring, Policy and Law

Cite this

Off-grid solar thermal water heating system using phase-change materials : design, integration and real environment investigation. / Prakash, Jyoti; Roan, Daryn; Tauqir, Wajeha; Nazir, Hassan; Ali, Majid; Mada Kannan, Arunachala.

In: Applied Energy, 15.04.2019, p. 73-83.

Research output: Contribution to journalArticle

@article{e0e2730436174824b5a7e6b434e4c1bc,
title = "Off-grid solar thermal water heating system using phase-change materials: design, integration and real environment investigation",
abstract = "A solar thermal water heating system using a custom-built latent heat storage tank with paraffin wax, puretemp68 and stearic acid/palmitic acid eutectic mixture based phase-change materials was designed, developed and its performance evaluated in real-time. The fully autonomous off-grid solar thermal water heating system was packaged by integrating solar thermal collector, phase change material tank, photovoltaic modules, operational controller, circulation pumps and battery, along with a data logger. A water-glycol with anti-freeze characteristics with efficient energy storage in cold weather was employed as heat transfer fluid for solar thermal energy harvesting for charging and discharging of phase change materials to heat the water tank. Solar charge-discharge and water charging results with phase change materials during May to October 2018 (Mesa, AZ 85212, USA) showed that the stearic acid/palmitic acid eutectic mixture outperformed the paraffin wax and exhibited comparable performance with puretemp68 storage system. The efficiency of water charging from stearic acid/palmitic acid (55{\%}) is higher compared to that from paraffin wax (20{\%}) and better than puretemp68 (45{\%}). Even though, the paraffin wax melts quickly during charging, it exhibited super-cooling behavior during discharging, leading to incomplete discharge. The storage energy density of stearic acid/palmitic acid (∼0.48 MJ kg −1 ) is comparable to puretemp68 with uniform thermal energy distribution inside the storage container due to higher thermal conductivity and lower melting point. The solar thermal water heating system demonstration proved that the domestic hot water system using stearic acid/palmitic acid could be a practical solution for effectively harvesting solar thermal energy for rural areas.",
keywords = "Latent heat, Off-grid system, Phase change material, Solar thermal water heating",
author = "Jyoti Prakash and Daryn Roan and Wajeha Tauqir and Hassan Nazir and Majid Ali and {Mada Kannan}, Arunachala",
year = "2019",
month = "4",
day = "15",
doi = "10.1016/j.apenergy.2019.02.058",
language = "English (US)",
pages = "73--83",
journal = "Applied Energy",
issn = "0306-2619",
publisher = "Elsevier BV",

}

TY - JOUR

T1 - Off-grid solar thermal water heating system using phase-change materials

T2 - design, integration and real environment investigation

AU - Prakash, Jyoti

AU - Roan, Daryn

AU - Tauqir, Wajeha

AU - Nazir, Hassan

AU - Ali, Majid

AU - Mada Kannan, Arunachala

PY - 2019/4/15

Y1 - 2019/4/15

N2 - A solar thermal water heating system using a custom-built latent heat storage tank with paraffin wax, puretemp68 and stearic acid/palmitic acid eutectic mixture based phase-change materials was designed, developed and its performance evaluated in real-time. The fully autonomous off-grid solar thermal water heating system was packaged by integrating solar thermal collector, phase change material tank, photovoltaic modules, operational controller, circulation pumps and battery, along with a data logger. A water-glycol with anti-freeze characteristics with efficient energy storage in cold weather was employed as heat transfer fluid for solar thermal energy harvesting for charging and discharging of phase change materials to heat the water tank. Solar charge-discharge and water charging results with phase change materials during May to October 2018 (Mesa, AZ 85212, USA) showed that the stearic acid/palmitic acid eutectic mixture outperformed the paraffin wax and exhibited comparable performance with puretemp68 storage system. The efficiency of water charging from stearic acid/palmitic acid (55%) is higher compared to that from paraffin wax (20%) and better than puretemp68 (45%). Even though, the paraffin wax melts quickly during charging, it exhibited super-cooling behavior during discharging, leading to incomplete discharge. The storage energy density of stearic acid/palmitic acid (∼0.48 MJ kg −1 ) is comparable to puretemp68 with uniform thermal energy distribution inside the storage container due to higher thermal conductivity and lower melting point. The solar thermal water heating system demonstration proved that the domestic hot water system using stearic acid/palmitic acid could be a practical solution for effectively harvesting solar thermal energy for rural areas.

AB - A solar thermal water heating system using a custom-built latent heat storage tank with paraffin wax, puretemp68 and stearic acid/palmitic acid eutectic mixture based phase-change materials was designed, developed and its performance evaluated in real-time. The fully autonomous off-grid solar thermal water heating system was packaged by integrating solar thermal collector, phase change material tank, photovoltaic modules, operational controller, circulation pumps and battery, along with a data logger. A water-glycol with anti-freeze characteristics with efficient energy storage in cold weather was employed as heat transfer fluid for solar thermal energy harvesting for charging and discharging of phase change materials to heat the water tank. Solar charge-discharge and water charging results with phase change materials during May to October 2018 (Mesa, AZ 85212, USA) showed that the stearic acid/palmitic acid eutectic mixture outperformed the paraffin wax and exhibited comparable performance with puretemp68 storage system. The efficiency of water charging from stearic acid/palmitic acid (55%) is higher compared to that from paraffin wax (20%) and better than puretemp68 (45%). Even though, the paraffin wax melts quickly during charging, it exhibited super-cooling behavior during discharging, leading to incomplete discharge. The storage energy density of stearic acid/palmitic acid (∼0.48 MJ kg −1 ) is comparable to puretemp68 with uniform thermal energy distribution inside the storage container due to higher thermal conductivity and lower melting point. The solar thermal water heating system demonstration proved that the domestic hot water system using stearic acid/palmitic acid could be a practical solution for effectively harvesting solar thermal energy for rural areas.

KW - Latent heat

KW - Off-grid system

KW - Phase change material

KW - Solar thermal water heating

UR - http://www.scopus.com/inward/record.url?scp=85061356455&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85061356455&partnerID=8YFLogxK

U2 - 10.1016/j.apenergy.2019.02.058

DO - 10.1016/j.apenergy.2019.02.058

M3 - Article

AN - SCOPUS:85061356455

SP - 73

EP - 83

JO - Applied Energy

JF - Applied Energy

SN - 0306-2619

ER -