Life cycle environmental and economic assessments of zeolite 13X-based space heating systems

• Author / Creator

  Tran, Tien Viet

• The important role of a heat storage system in the transition to a low carbon economy is widely acknowledged in scientific literature. In cold regions like Canada, where fossil-based space heating systems are widely used, the associated greenhouse gas emissions (GHGs) are a major concern. The use of a zeolite 13X adsorbent heat storage system for space heating provides a promising alternative when integrated with renewable resources such as solar and wind. This study developed a bottom-up techno-economic and life cycle assessment models to understand the economic viability and environmental sustainability of the proposed heating system. The storage system is designed to replace a traditional 16 kW furnace installed in an average single detached house in Canada over a 20-year lifetime.
  The life cycle greenhouse gas emissions are estimated to be 0.127 kg CO2 eq per kWh of delivered heat. The largest contribution is due to energy consumption in the operational phase (71% of the total emissions). The material production stage accounts for 28%, primarily a result of the upstream emissions in the manufacturing of air solar collectors. The system is energy efficient due to its net energy ratio of 3.2. The ratio of adsorbent vessel length to diameter and the pallet diameter appear to be the most sensitive parameters both for GHG emissions and net energy ratio. The uncertainty analysis shows that GHG emissions and net energy ratio of the space heating system are in the range of 90.1-205.4 g CO2 eq/kWh and 2.26-3.36, respectively. The low GHG emissions are a strong competitive aspect of zeolite-based space heating system.
  At a cost of $0.05 to 0.06 per kWh of produced heat, the system appears to be competitive with existing space heating systems such as hot water heating electric boiler and hot water heating gas-fired boiler. Photovoltaic thermal air solar collectors are the largest portion of the capital investment, about 67% of the total system cost. Length-to-diameter ratio, zeolite pallet diameter, and solar collector potential were found to be most sensitive variables in Morris sensitivity analysis. Additionally, the system has a scale factor of 0.761, as developed in this study. The research highlights that adsorbent storage using solar heat for space heating is an economically feasible and environmentally sound alternative to conventional heating. The information developed in this study could be used to make investment decisions and formulate policy.

• Subjects / Keywords

  • life cycle assessment
  • techno-economic assessment
  • space heating system
  • adsorbent
  • zeolite
  • zeolite 13X
  • net energy ratio

• Graduation date

  Fall 2021

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-efaa-bz11

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.