Experimental Study to Analyze Feasibility of a Novel Panelized Ground-Source Thermoelectric System for Building Space Heating and Cooling

A thermoelectric module is a device that converts electrical energy into thermal energy through a mechanism known as the Peltier effect. A Peltier device has hot and cold sides/substrates, and heat can be pumped from the cold side to the hot side under a given voltage. By applying it in buildings and attaching it to building envelope components, such as walls, as a heating and cooling device, the heating and cooling requirements can be met by reversing the voltage applied on these two sides/substrates. In this paper, we describe a novel, panelized, ground source, radiant system design for space heating and cooling in buildings by utilizing the Peltier effect. The system is equipped with water pipes that are attached to one side of the panel and connected with a ground loop to exchange heat between the cold/hot sides of the thermoelectric module and the underground region. The ground loop is inserted in boreholes, similar to those used for a vertical closed-loop Ground Source Heat Pump (GSHP) system, which could be more than a hundred meters deep. Experiments were conducted to evaluate the feasibility of the developed panel system applied in buildings. The results show that: (1) the average cooling Coefficients Of Performance (COP) of the system are low (0.6 or less) even though the ground is used as a heat sink, and thus additional studies are needed to improve it in the future, such as to arrange the thermoelectric modules in cascade and/or develop a new thermoelectric material that has a large Seebeck coefficient; and (2) the developed system using the underground region as the heat source has the potential of meeting heating loads of a building while maintaining at a higher system coefficient of performance (up to ~3.0) for space heating, compared to conventional heating devices, such as furnaces or boilers, especially in a region with mild winters and relatively warm ground.

Energy efficient house using ground source heat pump: mathematical model of thermal imbalance of soil around the ground loop

Energy efficient house using ground source heat pump: mathematical model of thermal imbalance of soil around the ground loop

Energy efficient house using ground source heat pump: mathematical model of thermal imbalance of soil around the ground loop

Energy efficient house using ground source heat pump: mathematical model of thermal imbalance of soil around the ground loop

Viability Of Hybrid Ground Source Heat Pump System With Solar Thermal Collectors

This thesis presents a study for examining the viability of hybrid ground source heat pump (GSHP) systems that use solar thermal collectors as the supplemental component in heating dominated buildings. Loads for an actual house in the City of Milton near Toronto were estimated. TRNSYS, a system simulation software tool, was used to model the yearly performance of conventional GSHP as well as the proposed hybrid GSHP system. The house was equipped with a data monitoring system which was installed to read and record fluid flow, temperature and electricity consumption in different components of the system. The actual yearly data collected from the site was examined against the simulation results. In addition, a sensitivity analysis was carried out to determine the relationship between the solar collector area and the ground loop heat exchanger (GHX) length. It was shown that the ratio of GHX length reduction to solar panel area of 4.7 m/m This study demonstrates that a hybrid GSHP system, combined with solar thermal collectors, is a feasible choice for space conditioning for heating dominated houses. It was shown that the solar thermal energy storage in the ground could reduce a large amount of ground loop heat exchanger length. Combining three solar thermal collectors with a total area of 6.81m

Viability Of Hybrid Ground Source Heat Pump System With Solar Thermal Collectors

This thesis presents a study for examining the viability of hybrid ground source heat pump (GSHP) systems that use solar thermal collectors as the supplemental component in heating dominated buildings. Loads for an actual house in the City of Milton near Toronto were estimated. TRNSYS, a system simulation software tool, was used to model the yearly performance of conventional GSHP as well as the proposed hybrid GSHP system. The house was equipped with a data monitoring system which was installed to read and record fluid flow, temperature and electricity consumption in different components of the system. The actual yearly data collected from the site was examined against the simulation results. In addition, a sensitivity analysis was carried out to determine the relationship between the solar collector area and the ground loop heat exchanger (GHX) length. It was shown that the ratio of GHX length reduction to solar panel area of 4.7 m/m This study demonstrates that a hybrid GSHP system, combined with solar thermal collectors, is a feasible choice for space conditioning for heating dominated houses. It was shown that the solar thermal energy storage in the ground could reduce a large amount of ground loop heat exchanger length. Combining three solar thermal collectors with a total area of 6.81m

Towards determining the effect of shallow depth horizontal ground loop clearance on the heat loss of a single family residential dwelling

Using solar energy stored in the ground to preheat incoming fresh ventilation air with ground loops is a renewable energy system which is becoming more frequently used in new residential developments. The purpose of this research was to examine the effect of ground loop to foundation wall clearance on building heat loss. Additionally, the thermal properties of the soil were examined to determine their impact on the ground loop’s effect on heat loss. A simulation based research approach was conducted using HEAT3, which is a three-dimensional transient heat transfer software. This study found that ground loop clearance had a larger impact on building heat loss for areas with low thermal conductivity soils than for areas with high thermal conductivity soils. On average, ground loop clearances of 10cm, 50cm, 100cm, and 200cm resulted in increased building heat losses of 20%-83%, 19%-55%, 16%-35%, and 12%-15% respectively.

Development of an automated device for testing the external ground loop of power lines

The article refers to the need for periodic tests of grounding of power lines, in connection with which there is a need to develop domestic devices for conducting such tests, and a prototype of such a device has been developed

Technico-economic modelling of ground and air source heat pumps in a hot and dry climate

In a hot and dry country such as Saudi Arabia, air-conditioning systems consume seventy per cent of the electrical energy. In order to reduce this demand, conventional air -conditioning technology should be replaced by more efficient renewable energy systems. These should be compared to the current standard systems which use air source heat pumps (ASHPs). These have a poor performance when the air temperature is high. In Saudi Arabia, this can be as much as 50 °C. The purpose of this work, therefore, is to simulate and evaluate the performance of ground source heat pumps (GSHPs) compared with systems employing (ASHPs). For the first time, both systems were comprehensively modelled and simulated using the Transient System Simulation (TRNSYS). In addition, the Ground Loop Design (GLD) software was used to design the length of the ground loop heat exchanger. In order to assess this configuration, an evaluation of a model of a single story office building, based on the climatic conditions and geological characteristics that occur in the city of Riyadh in Saudi Arabia was investigated. The period of evaluation was twenty years in order to determine the Coefficient of Performance (COP), Energy Efficiency Ratio (EER) and power consumption. The simulation results show that the GSHP system has a high performance when compared to ASHP. The average annual COP and EER were 4.1 and 15.5 for the GSHP compared to 3.8 and 11 for the ASHP respectively, and the GSHP is a feasible alternative to ASHP with an 11 years payback period with an 18% total cost saving over the simulation period and 36% lower annual energy consumption. The TRNSYS model shows that despite the positive results of the modeling, the high rate of the underground thermal imbalance (88%) could lead to a system failure in the long term

Electromagnetic Shielding Performance Measurement for Braided-Shield Power Cables at Low Frequency Regimes

Although various measurement techniques have been applied to both qualitative and quantitative evaluation for the electromagnetic shielding performance of braided-shield power cables, the existing measurements cannot directly assess the low-frequency shielding performance (typically below 100 kHz) due to factors such as ground-loop effects and dynamic range problem in measurement. To solve these, an improved shield reduction factor method, based on gain (T/R) rather than scattering parameters, is proposed to evaluate the shielding performance of braided-shield power cables from 25 Hz to 1 MHz. In this work, we highlight the implementation of measurement setup to avoid the effects of ground-loop and stray electromagnetic field. Meanwhile, the test cell is simplified according to the definition of the shield reduction factor in order to obtain the gain (T/R) parameters, which can be used to calculate transfer impedance as well. From the measurements we present more intuitive evaluation of shielding behavior of braided-shield power cables at low frequency regimes, and showcase a detailed comparative discussion between transfer impedance and shield reduction factor. The proposed shield reduction factor method is expected to be a useful way for the evaluation of the low frequency shielding performance of braided-shield cables.