A thermoelectric building envelope (TBE) is a new type of active building envelope that incorporates thermoelectric material in the building's enclosure. In TBE, the electrical energy and thermal energy can transfer between them through thermoelectric material. As a result, TBE can provide cooling or heating to indoor space if power is applied. TBE-based cooling or heating has high reliability and a low maintenance cost, low CO2 emission, and no refrigerant use. TBE is conducive to the operation of net-zero energy and greenhouse gas emission buildings by using renewable energy. In this study, a multi-stage TBE prototype for space heating and cooling was designed, assembled, and tested. The performance of the TBE prototype was evaluated in two psychrometric chambers with controlled temperature and humidity in Herrick Laboratory at Purdue University. The performance was analyzed, including the surface and air temperatures, cooling capacity, and COP defined as the ratio of cooling capacity to the power input. The test result indicated that the COP of TBE in summer scenarios ranged from 0.46 to 2.4 with varied power inputs. The cooling capacity of one prototype can exceed 6.3 kW/cm2. The findings discussed can guide the design and operation of TBE.
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Performance Modeling and Analysis of a Thermoelectric Building Envelope for Space Heating.
To provide energy-efficient space heating and cooling, a thermoelectric building envelope (TBE) embeds thermoelectric devices in building walls. The thermoelectric device in the building envelope can provide active heating and cooling without requiring refrigerant use and energy transport among subsystems. Thus, the TBE system is energy and environmentally friendly. A few studies experimentally investigated the TBE under limited operating conditions, and only simplified models for the commercial thermoelectric module (TEM) were developed to quantify its performance. A holistic approach to optimum system performance is needed for the optimal system design and operation. The study developed a holistic TBE-building system model in Modelica for system simulation and performance analysis. A theoretical model for a single TEM was first established based on energy conversion and thermoelectric principles. Subsequently, a TBE prototype model combining the TEM model was constructed. The prototype model employing a feedback controller was used in a whole building system simulation for a residential house. The system model computed the overall building energy efficiency and dynamic indoor conditions under varying operating conditions. Simulation results indicate the studied TBE system can meet a heating demand to maintain the desired room temperature at 20 °C when the lowest outdoor temperature is at -26.3 °C, with a seasonal heating COP near 1.1, demonstrating a better heating performance than electric heaters. It suggests a potential energy-efficient alternative to the traditional natural gas furnaces and electric heaters for space heating.
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- Award ID(s):
- 1805818
- NSF-PAR ID:
- 10348987
- Date Published:
- Journal Name:
- 2022 (7th) International High Performance Buildings Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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A thermoelectric building envelope (TBE) is a new type of active building envelope that incorporates thermoelectric material in the building’s enclosure. In TBE, the electrical energy and thermal energy can transfer between them through thermoelectric material. TBE can provide cooling or heating to indoor space if power is applied. TBE-based cooling or heating is quiet and reliable and has low maintenance cost, low or no CO2 emission. TBE is conducive to the operation of net-zero energy and emission buildings by using renewable and low-grade energy. In this study, a multi-stage TBE prototype was designed, assembled, and tested. The performance of the TBE prototype was evaluated in two psychrometric chambers with controlled temperature and humidity in Herrick Laboratory at Purdue University. The test result concludes that the highest COP of TBE is 0.46–2.4 in summer scenarios for different power inputs. The findings discussed can guide the design and operation of TBE.more » « less
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