Building-Integrated Thermoelectrics as Active Insulators and Heat Pumps

2007 ◽  
Author(s):  
Leon M. Headings ◽  
Gregory N. Washington
Keyword(s):  
Air Conditioning ◽  
Energy Transport ◽  
Heat Pumps ◽  
Building Envelope ◽  
Coefficient Of Performance ◽  
Thermal Mass ◽  
Energy Prices ◽  
Commercial Building ◽  
Design And Optimization ◽  
Heating And Cooling

Heating, ventilation, and air conditioning (HVAC) accounts for 40% to 60% of residential and commercial building energy consumption, making this a critical component of energy usage in the face of rising energy prices. Building-integrated thermoelectrics (BITE) may provide a step towards adaptive homes and buildings that offer significantly improved efficiency and comfort. Integrating thermoelectrics into thermal mass and resistance (insulation) wall systems presents a fundamental shift from optimizing heating and cooling source efficiencies and minimizing building-envelope energy losses to a new regime where an active envelope is optimized to most efficiently eliminate those losses. This approach not only offers improved energy efficiency, but improves the uniformity and consistency of temperature, eliminates the need for all other heating and air conditioning equipment including thermal energy transport, and provides the platform for adaptive zone heating and cooling which can provide additional efficiency gains. Because of the solid-state nature of thermoelectrics, such a system would be reliable, low maintenance, silent, and clean. This paper examines various wall configurations and sizing for thermal mass, resistance, and thermoelectric components. A dynamic simulation is used to demonstrate how proper system design of thermal resistance and capacitance elements with existing thermoelectric materials may improve the typically low coefficient of performance of thermoelectric devices, making it competitive with traditional building systems. The results for different wall configurations are shown as a basis for future configuration design and optimization.

Design and experimental analysis of a solar thermoelectric heating, ventilation, and air conditioning system as an integral element of a building envelope

2018 ◽  
Vol 40 (2) ◽  
pp. 220-236 ◽  
Author(s):  
Irfan Ahmad Gondal
Keyword(s):  
Experimental Analysis ◽  
Air Conditioning ◽  
Energy Use ◽  
New Technologies ◽  
Thermoelectric Module ◽  
Electrical Current ◽  
Building Envelope ◽  
Coefficient Of Performance ◽  
Heating And Cooling ◽  
Cooling Effects

This study presents an innovative concept of a compact integrated solar-thermoelectric module that can form part of the building envelope. The heating/cooling modes use the photovoltaic electrical current to power the heat pump. The experimental analysis was carried out and the results of coefficient of performance were in the range 0.5–1 and 2.6–5 for cooling and heating functions, respectively. The study demonstrates that thermoelectric cooler can effectively be used for heating, ventilation, and air conditioning applications by integrating with solar panels especially in cooling applications. The system is environmentally friendly and can contribute in the implementation of zero energy buildings concept. Practical application: In order to help address the challenge of climate change and associated environmental effects, there is continuous demand for new technologies and applications that can be readily integrated into day-to-day life as a means of reducing anthropogenic impact. Heating, ventilation, and air conditioning, as one of the largest energy consumers in buildings, is the focus of many researchers seeking to reduce building energy use and environmental impact. This article proposes using facades and windows that have an integrated modules of solar photovoltaic cells and thermoelectric devices that are able to work together to achieve heating and cooling effects as required by the building without requiring any external operational power.

scholarly journals Thermal Zones Modelling for an Energy Efficient Commercial Building – Case Study

2019 ◽  
Vol 111 ◽  
pp. 03034
Author(s):  
Elena Camelia Tamaş (Papuc) ◽  
Dragoş Hera ◽  
Gianni Flamaropol ◽  
Graţiela Maria Ţârlea
Keyword(s):  
Air Conditioning ◽  
Building Energy ◽  
Building Envelope ◽  
Weather Data ◽  
Commercial Building ◽  
Heating And Cooling ◽  
Modelling Analysis ◽  
Building Geometry ◽  
Lighting Systems

Our paper is referring to a commercial building having a good thermal insulation, compacted shape with three basements, from which two are for parking and technical areas in the underground, and the other floors are mainly for retail, technical rooms, offices and a terrace for walking and events. The methodology used in our building thermal zones modelling analysis is including: all used measured areas within the building; all materials related to the building envelope with high thermal efficiency values; all activities performed within the respective areas; the heating and cooling activities for each zone; the lighting and controls used for each zone; the building geometry related to the data requirements, loads, air conditioning and lighting systems areas; the building usage schedules; Heating Ventilation and Air Conditioning (HVAC) and electrical system specifications along the weather data. The building thermal zones modelling simulation was performed based on the air set point temperature, ventilation fresh air rate and the room destination. After monitoring the building along four operational years, the energy consumptions for heating and cooling systems were obtained for each thermal zone and for the entire building. Some technical measures to improve the building energy performances are proposed based on the monitoring period.

Modeling and Design of Building-Integrated Thermoelectrics

2011 ◽  
Author(s):  
Leon M. Headings ◽  
Gregory N. Washington
Keyword(s):  
Thermal Response ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Conventional Heating ◽  
Net Energy ◽  
Arbitrary Boundary ◽  
Heating And Cooling ◽  
Temperature Oscillations ◽  
Wall Structures ◽  
And Control

The goal of this research is to develop a framework for replacing conventional heating and cooling systems with distributed, continuously and electrically controlled, building-integrated thermoelectric (BITE) heat pumps. The coefficient of performance of thermoelectric heat pumps increases as the temperature difference across them decreases and as the amplitude of temperature oscillations decreases. As a result, this research examines how thermal insulation and mass elements can be integrated with thermoelectrics as part of active multi-layer structures in order to minimize net energy consumption. In order to develop BITE systems, an explicit finite volume model was developed to model the dynamic thermal response of active multi-layer wall structures subjected to arbitrary boundary conditions (interior and exterior temperatures and interior heat loads) and control algorithms. Using this numerical model, the effects of wall construction on net system performance were examined. These simulation results provide direction for the ongoing development of BITE systems.

Preliminary Feasibility Study of Groundwater Source Geothermal Heat Pumps in Mason County and the American Bottoms Area, Illinois

2014 ◽  
Author(s):  
Xinli Lu ◽  
David R. Larson ◽  
Thomas R. Holm
Keyword(s):  
Ground Surface ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Weather Data ◽  
Single Family ◽  
Geothermal Heat ◽  
Geothermal Heating ◽  
Heating And Cooling ◽  
Groundwater Source ◽  
Mason County

Groundwater source heat pumps exploit the difference between the ground surface temperature and the nearly constant temperature of shallow groundwater. This project characterizes two areas for geothermal heating and cooling potential, Mason County in central Illinois and the American Bottoms area in southwestern Illinois. Both areas are underlain by thick sand and gravel aquifers and groundwater is readily available. Weather data, including monthly high and low temperatures and heating and cooling degree days, were compiled for both study areas. The heating and cooling requirements for a single-family house were estimated using two independent models that use weather data as input. The groundwater flow rates needed to meet these heating and cooling requirements were calculated using typical heat pump coefficient of performance values. The groundwater in both study areas has fairly high hardness and iron concentrations and is close to saturation with calcium and iron carbonates. Using the groundwater for cooling may induce the deposition of scale containing one or both of these minerals.

scholarly journals Heat pump systems: A mini review

2021 ◽  
Vol 4 (2) ◽  
pp. 73-81
Author(s):  
Mohammad Omar Temori ◽  
František Vranay
Keyword(s):  
Heat Pump ◽  
Electricity Consumption ◽  
Cost Savings ◽  
Electrical Energy ◽  
Primary Energy ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Heating And Cooling ◽  
Ground Source ◽  
Reduce Electricity Consumption

In this work, a mini review of heat pumps is presented. The work is intended to introduce a technology that can be used to income energy from the natural environment and thus reduce electricity consumption for heating and cooling. A heat pump is a mechanical device that transfers heat from one environmental compartment to another, typically against a temperature gradient (i.e. from cool to hot). In order to do this, an energy input is required: this may be mechanical, electrical or thermal energy. In most modern heat pumps, electrical energy powers a compressor, which drives a compression - expansion cycle of refrigerant fluid between two heat exchanges: a cold evaporator and a warm condenser. The efficiency or coefficient of performance (COP), of a heat pump is defined as the thermal output divided by the primary energy (electricity) input. The COP decreases as the temperature difference between the cool heat source and the warm heat sink increases. An efficient ground source heat pump (GSHP) may achieve a COP of around 4. Heat pumps are ideal for exploiting low-temperature environmental heat sources: the air, surface waters or the ground. They can deliver significant environmental (CO2) and cost savings.

scholarly journals Recovery and Utilization of Low-Grade Waste Heat in the Oil-Refining Industry Using Heat Engines and Heat Pumps: An International Technoeconomic Comparison

Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2560 ◽  
Author(s):  
Nikunj Gangar ◽  
Sandro Macchietto ◽  
Christos N. Markides
Keyword(s):  
Heat Source ◽  
Thermal Energy ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Oil Refining ◽  
Low Grade ◽  
Energy Prices ◽  
Steam Generation ◽  
Electricity Prices ◽  
Oil Refineries

We assess the technoeconomic feasibility of onsite electricity and steam generation from recovered low-grade thermal energy in oil refineries using organic Rankine cycle (ORC) engines and mechanical vapour compression (MVC) heat pumps in various countries. The efficiencies of 34 ORC and 20 MVC current commercial systems are regressed against modified theoretical models. The resulting theoretical relations predict the thermal efficiency of commercial ORC engines within 4–5% and the coefficient of performance (COP) of commercial MVC heat pumps within 10–15%, on average. Using these models, the economic viability of ORC engines and MVC heat pumps is then assessed for 19 refinery streams as a function of heat source and sink temperatures, and the available stream thermal energy, for gas and electricity prices in selected countries. Results show that: (i) conversion to electrical power with ORC engines is, in general, economically feasible for heat-source temperatures >70 °C, however with high sensitivity to energy prices; and (ii) steam generation in MVC heat pumps, even more sensitive to energy prices, is in some cases not economical under any conditions—it is only viable with high gas/low electricity prices, for large heat sources (>2 MW) and higher temperatures (>140 °C). In countries and conditions with positive economics, payback periods down to two years are found for both technologies.

Dynamic Simulation of Organic Rankine Cycle-Assisted Ground-Source Heat Pump Based Micro-Cogeneration System in Cold Climates: A Case Study in Canada

2021 ◽  
Author(s):  
Wahiba Yaïci ◽  
Evgueniy Entchev ◽  
Michela Longo
Keyword(s):  
Storage Temperature ◽  
Organic Rankine Cycle ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Net Energy ◽  
Combined System ◽  
Ground Source Heat Pumps ◽  
Heating And Cooling ◽  
Ground Source ◽  
Cogeneration System

Abstract As the energy needed for heating and cooling involves a substantial amount (> 80%) of residential energy utilisation in Canada, there is a demand for ultra-efficient energy systems for heating, cooling, and power generation. Two efficient systems to assist these systems are ground-source heat pumps (GSHPs) and organic Rankine cycles (ORCs). Of particular interest, this paper presents the integration of these two systems in a parallel configuration. A transient simulation model developed in TRNSYS program has been utilised to simulate the thermal performance of the combined ORC-GSHP based microco/trigeneration system. This later supplies heating and cooling to the residential load during the heating mode as required, with the capability to switch to a charging mode, where the ORC unit is directly coupled to the ground heat exchanger (GHE), which operates as a thermal energy storage and provides energy to the GSHP. The feasibility of this combined system configuration as well as its comparison with a conventional GSHP system are investigated for use in residential application in Ottawa, Canada temperature conditions. Results disclosed that the proposed micro-cogeneration system had the operating hours and performance of the GSHP improved by the addition of the ORC unit, resulting in about 11.8% reduction in hours in the colder city of Ottawa. The COP (coefficient of performance) of the GSHP system sustained a much higher value overall due to the addition of the ORC system to maintain the GHE storage temperature. In terms of net energy reduction between the conventional GSHP system and the ORC-assisted one, results revealed that Ottawa had energy usage reduction of 82.0%, demonstrating that the addition of an ORC to provide heating and recharge the GHE of a GSHP system has many advantages that could be accomplished by the end-user.

scholarly journals Modeling of an Air Conditioning System with Geothermal Heat Pump for a Residential Building

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Silvia Cocchi ◽  
Sonia Castellucci ◽  
Andrea Tucci
Keyword(s):  
Heat Pump ◽  
Air Conditioning ◽  
Residential Building ◽  
Heat Pumps ◽  
Geothermal Heat ◽  
Air Conditioning System ◽  
Heating And Cooling ◽  
Ground Source ◽  
Geothermal Heat Pump ◽  
Geothermal Plant

The need to address climate change caused by greenhouse gas emissions attaches great importance to research aimed at using renewable energy. Geothermal energy is an interesting alternative concerning the production of energy for air conditioning of buildings (heating and cooling), through the use of geothermal heat pumps. In this work a model has been developed in order to simulate an air conditioning system with geothermal heat pump. A ground source heat pump (GSHP) uses the shallow ground as a source of heat, thus taking advantage of its seasonally moderate temperatures. GSHP must be coupled with geothermal exchangers. The model leads to design optimization of geothermal heat exchangers and to verify the operation of the geothermal plant.

Design and Testing of a Separate Sensible and Latent Cooling Packaged Terminal Air Conditioning Unit

2015 ◽  
Author(s):  
Abdullah Alabdulkarem ◽  
Michael Cristiano ◽  
Yunho Hwang ◽  
Reinhard Radermacher
Keyword(s):  
Air Conditioning ◽  
System Optimization ◽  
Cooling Capacity ◽  
Lessons Learned ◽  
Coefficient Of Performance ◽  
Vapor Compression ◽  
Cost Study ◽  
Climate Conditions ◽  
Future Design ◽  
Heating And Cooling

Packaged terminal air conditioning (PTAC) systems are typically utilized for space heating and cooling in hotels and apartment buildings. However, they cool the air to low temperature for dehumidification and some reheating may be required to resolve overcooling. A prototype of a solid desiccant wheel assisted separate sensible and latent cooling (SSLC) PTAC system was designed and constructed, which has a cooling capacity of 3.5 kW. The heat exchangers and vapor compression cycle were modeled in in-house software, CoilDesigner and VapCyc. The modeling results show improvement in the coefficient of performance from 3.12 to 4.05 or 30%. Cost study was conducted to evaluate the economics of SSLC PTAC units within the U.S. climate conditions. The study shows the payback period for the national average could be as low as 2 years. The system was experimentally tested and its performance was not as expected due to some design challenges. This paper highlights the lessons learned from the modeling and experimental work and discusses the economic analysis in addition to future design improvements and system optimization.

Analysis of Building Envelope Performance Effects of an Insulating Semi-Transparent Photovoltaic (STPV) Glazing Unit

2014 ◽  
Author(s):  
Dirk V. P. McLaughlin ◽  
Konstantinos Kapsis ◽  
Andreas K. Athienitis ◽  
Sam Siassi ◽  
Livio Nichilo
Keyword(s):  
Performance Standards ◽  
Energy Performance ◽  
Building Envelope ◽  
Commercial Building ◽  
Heating And Cooling ◽  
Performance Effects ◽  
Gas Consumption ◽  
U Value ◽  
And Performance ◽  
Cooling Loads

This paper presents characterization results for the electrical and thermal properties of a unique insulating semi-transparent photovoltaic (STPV) glazing unit using calorimetry hot box methods finding a U-value of 1.09 W/m2·°C and a SHGC of 0.11. These properties are then applied to an energy model of a case study commercial building in a continental climate region to examine the effects of utilizing STPV in the building envelope on the electricity and natural gas consumption levels and peak demands. The results indicate that such a building envelope can significantly reduce heating and cooling loads compared to standard glazing which would help architects maintain the desirable properties of highly glazed façades while avoiding the drop in building energy performance that could make adhering to increasingly stringent building codes and performance standards difficult. The paper also presents simulation results for the photovoltaic energy generation of the vertical STPV façades at two building orientations.

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