Cooling Towers as Supplemental Heat Rejection Systems in Ground Source Heat Pumps for Residential Houses in Texas and Other Semi-Arid Regions

2012 ◽  
Author(s):  
Siddharth Balasubramanian ◽  
Jonathan Gaspredes ◽  
Tess J. Moon ◽  
Glenn Y. Masada
Keyword(s):  
Heat Pump ◽  
Cooling Tower ◽  
Cost Effective ◽  
Heat Pumps ◽  
Residential Home ◽  
Test Case ◽  
Pump Efficiency ◽  
Ground Source Heat Pump ◽  
Ground Source Heat Pumps ◽  
Ground Source

Simulation results from a hybrid ground source heat pump model are presented for a residential home that integrates a compact cooling tower into an existing ground source heat pump model. The tower is introduced to assess its impact on the operational and economic performance over that of a GSHP alone. Metrics include initial and lifetime operational costs, ground heating effects, heat pump efficiency, and ability to control the temperature of the conditioned space. A single story, 195 m2 house located in Austin, Texas is used as a cooling-dominated test case. Simulations spanning 10-years of operation show that adding the cooling tower is cost effective, but more importantly, it extends the lifetime of the borehole system and maintains the heat pump efficiencies at high levels.

scholarly journals Ground-Source Heat Pumps with Horizontal Heat Exchangers for Space Cooling in the Hot Tropical Climate of Thailand

Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1274 ◽  
Author(s):  
Arif Widiatmojo ◽  
Sasimook Chokchai ◽  
Isao Takashima ◽  
Yohei Uchida ◽  
Kasumi Yasukawa ◽  
...  
Keyword(s):  
Economic Growth ◽  
Heat Pump ◽  
Heat Exchangers ◽  
Life Cycle Cost ◽  
Heat Pumps ◽  
Ground Source Heat Pump ◽  
Ground Source Heat Pumps ◽  
Air Source Heat Pump ◽  
Ground Source ◽  
Space Cooling

The cooling of spaces in tropical regions, such as Southeast Asia, consumes a lot of energy. Additionally, rapid population and economic growth are resulting in an increasing demand for space cooling. The ground-source heat pump has been proven a reliable, cost-effective, safe, and environmentally-friendly alternative for cooling and heating spaces in various countries. In tropical countries, the presumption that the ground-source heat pump may not provide better thermal performance than the normal air-source heat pump arises because the difference between ground and atmospheric temperatures is essentially low. This paper reports the potential use of a ground-source heat pump with horizontal heat exchangers in a tropical country—Thailand. Daily operational data of two ground-source heat pumps and an air-source heat pump during a two-month operation are analyzed and compared. Life cycle cost analysis and CO2 emission estimation are adopted to evaluate the economic value of ground-source heat pump investment and potential CO2 reduction through the use of ground-source heat pumps, in comparison with the case for air-source heat pumps. It was found that the ground-source heat pumps consume 17.1% and 18.4% less electricity than the air-source heat pump during this period. Local production of heat pumps and heat exchangers, as well as rapid regional economic growth, can be positive factors for future ground-source heat pump application, not only in Thailand but also southeast Asian countries.

scholarly journals Sensitivity analysis using simulations for a ground source heat pump – implementation on a solar passive house

2019 ◽  
Vol 111 ◽  
pp. 01070
Author(s):  
Gheorghe Ilisei ◽  
Tiberiu Catalina ◽  
Robert Gavriliuc
Keyword(s):  
Sensitivity Analysis ◽  
Heat Pump ◽  
Fossil Fuels ◽  
Electricity Consumption ◽  
Heat Pumps ◽  
Ground Source Heat Pump ◽  
Passive House ◽  
Modeling Tools ◽  
Ground Source Heat Pumps ◽  
Ground Source

Having in sight the need for a strong reduction in CO2 emissions and the fluctuation of the price of fossil fuels, the ground source resources alongside with the ground source heat pumps are becoming more and more widespread for meeting the heating/cooling demand of several types of buildings. This article targets to develop the thermal modelling of borehole heat storage systems. Trying to emphasize some certain advantages of a GSHP (ground source heat pump) with vertical boreholes, a case study analysing a residential solar passive house is presented. The numerical results are produced using different modelling software like DesignBuilder, EED (Earth Energy Designer) and a sizing method for the length of the boreholes (ASHRAE method). The idea of sizing the length of boreholes (main design parameter and good index in estimating the system’s cost) using two different methods shows the reliability of this modelling tool. The study shows that borehole’s length of a GSHP system can trigger a difference in electricity consumption up to 22%. Moreover, this sensitivity analysis aims to prove that the design of the whole system can be done beforehand just using modeling tools, without performing tests in-situ.

scholarly journals Selection and techno-economic analysis of hybrid ground source heat pumps used in karst regions

2020 ◽  
Vol 103 (2) ◽  
pp. 003685042092168
Author(s):  
Weisong Zhou ◽  
Peng Pei ◽  
Ruiyong Mao ◽  
Haibin Qian ◽  
Yanbing Hu ◽  
...  
Keyword(s):  
Economic Analysis ◽  
Heat Pump ◽  
Groundwater Resources ◽  
Heat Pumps ◽  
Ground Source Heat Pump ◽  
Pump System ◽  
Ground Source Heat Pumps ◽  
Ground Source ◽  
Heat Buildup

In order to take advantage of different forms of heat pumps and to mitigate thermal imbalance underground caused by long-term operation of ground source heat pumps, hybrid ground source heat pump systems have received an increasing attention. In this research, based on the fact that abundant groundwater resources are commonly available in karst regions, a new strategy is introduced for selecting and determining hybrid ground source heat pump capacity. Five scenarios of hybrid ground source heat pump system coupling groundwater source heat pumps with other supplementary heat pumps are proposed in this article to provide appropriate options to eliminate heat buildup under different hydrogeologic conditions. Methodologies for sizing and selection are established. Then, a case study of techno-economic analysis was performed for a project in the karst region in South China. The results showed that these scenarios can effectively mitigate heat buildup, and under the hydrogeologic condition in the case study. Compared to the solo ground-coupled heat pump solution, the optimal solution (Solution 4 in this study) can reduce the annual costs by 16.10% and reduce the capital investment by 60%. Methodologies developed in this study are beneficial for selecting appropriate approaches to mitigate heat buildup and enhance competitiveness of ground source heat pumps.

scholarly journals Measurement and Verification of Integrated Ground Source Heat Pumps on a Shared Ground Loop

Energies ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1752 ◽  
Author(s):  
Jeong Soo Shin ◽  
Jong Woo Park ◽  
Sean Hay Kim
Keyword(s):  
Heat Pump ◽  
Air Conditioning ◽  
Heat Pumps ◽  
Hot Water ◽  
Geothermal System ◽  
Ground Source Heat Pump ◽  
Pump System ◽  
Ground Source Heat Pumps ◽  
Water Service ◽  
Ground Source

We propose an integrated geothermal system that consists of air-conditioning and hot water service ground source heat pumps, both of which share a ground water loop. The proposed system increases the COP of the service hot water ground source heat pump by recovering the condensation heat of the air-conditioning ground source heat pump as an evaporator heat source for the hot water service ground source heat pump. Eventually this integration expands the scope and capacity of the evaporator source in addition to the underground water of heat exchangers, which also leads to increase the COP of the air-conditioning ground source heat pump. The integrated geothermal heat pump system was installed in a hotel, and then data were measured for a limited period due to the hotel’s ongoing business activities. A TRNSYS simulation model has been developed as a baseline, and the baseline has been calibrated with the measured data. By running one-year simulations, it turns out that the annual electricity use for heating and cooling, and service hot water was reduced by 19.1% in the cooling season, and by 9.6% in the heating season, with respect to the conventional configuration in which the air-conditioning heat pump and hot water service heat pump work individually on their own ground loops.

Development of design guidelines for thermo-active foundations

2017 ◽  
Vol 27 (6) ◽  
pp. 805-817 ◽  
Author(s):  
Byung C. Kwag ◽  
Moncef Krarti
Keyword(s):  
Heat Pump ◽  
Heat Pumps ◽  
Design Guidelines ◽  
Conventional Heating ◽  
Ground Source Heat Pump ◽  
External Energy ◽  
Geothermal Heat ◽  
Ground Source Heat Pumps ◽  
Heating And Cooling ◽  
Ground Source

Ground medium can be utilized as a direct energy source to heat and cool buildings. In particular, ground source heat pump systems take advantage of the year-round mild deep earth temperature without a significant reliance on any external energy sources. However, the high installation cost of ground source heat pumps associated with high drilling cost of vertical boreholes often make these systems less cost-effective compared to conventional heating and cooling systems. Thermo-active foundations can be a viable solution to reduce ground source heat pump high installation costs by embedding heat exchangers within building foundation structures. Compared to ground source heat pumps, only limited analyses and research studies have been reported for thermo-active foundations especially for the US climates. In particular, no specific design guidelines have been reported for thermo-active foundations especially for US climates. In this paper, a simplified design approach was developed and applied for specifying geothermal heat pump size and heat exchanger loop length to meet all or part of building heat and cooling thermal loads. The developed guidelines would thus provide a proper design guide for installation of thermo-active foundations for heating and cooling of both US residential and commercial buildings.

scholarly journals Combining Building Renovation and Ground Source Heat Pump Installations for the Reduction of Greenhouse Gas Emissions: A Case Study in Vaasa Finland

2009 ◽  
Vol 4 (1) ◽  
pp. 146-168
Author(s):  
Joyce Cooper ◽  
Tarja Häkkinen ◽  
Sirje Vares ◽  
Jenni Jahn ◽  
Sakari Pulakka
Keyword(s):  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Heat Pump ◽  
Heat Pumps ◽  
Heat Sources ◽  
Ground Source Heat Pump ◽  
Ground Source Heat Pumps ◽  
Gas Emissions ◽  
Ground Source

Given the growing interest in ground source heat pump and distributed heating installations in general for the reduction of greenhouse gas emissions, technology implementation planning can benefit from the simultaneous consideration of building renovations. Here, a method for identifying and evaluating scenarios based on cost and greenhouse gas emissions is presented. The method is demonstrated for a case study in Vaasa Finland. The case study considers the insulation of the walls, roof, and base floor and the replacement of windows based on 2003 and 2010 Finnish building codes simultaneously with the possible replacement of existing heat sources with ground source heat pumps. Estimates of changes in heat demand for consecutive renovations are combined with data on renovation, installation, heating costs, and life cycle greenhouse gas emissions data for the current and proposed heat sources. Preferred scenarios are identified and evaluated by building type, construction decade, and current heating source. The results are then placed within the contexts of the Vaasa building stock and policy theory.

Evaluation of Ground Source Heat Pump Energy, Demand, and Greenhouse Potential in Colorado Residential Buildings

2010 ◽  
Author(s):  
Daniel Studer ◽  
Moncef Krarti
Keyword(s):  
Heat Pump ◽  
Energy Demand ◽  
Residential Buildings ◽  
Pump Energy ◽  
Hvac Systems ◽  
Heat Pumps ◽  
Ground Source Heat Pump ◽  
Ground Source Heat Pumps ◽  
Vertical Well ◽  
Ground Source

This paper summarizes the results of a detailed energy analysis carried out for a typical Colorado residence using three different HVAC systems for 10 distinct locations in Colorado. The HVAC systems considered in the analysis include: • 78% efficient furnace with a 13 SEER air conditioner; • Vertical well ground source heat pump with a heating COP of 3.5 and a cooling EER of 17.1; • Slinky ground source heat pump with a heating COP of 3.5 and a cooling EER of 17.1. The results of the analysis indicate that relative to the conventional systems, ground source heat pumps (GSHPs) offer several benefits including lower annual energy costs, electrical peak demand, and carbon emissions. However, GSHPs use more electrical energy use. Specifically, it was found that relative to a 78 AFUE furnace / 13 SEER AC system, in all locations both GSHPs, vertical well and slinky, show on average a 41.2% increase in electricity use, a 10% decrease in energy cost, a 4.5% decrease in CO2 emissions, and a 16.8% average decrease in peak summer electric demand.

scholarly journals Seasonal storage of residential exhaust air and sewage waste heat

2021 ◽  
Vol 246 ◽  
pp. 06009
Author(s):  
Janne Hirvonen ◽  
Juha Jokisalo ◽  
Risto Kosonen
Keyword(s):  
Heat Pump ◽  
Waste Heat ◽  
Residential Buildings ◽  
Heat Pumps ◽  
Ground Source Heat Pump ◽  
Pump System ◽  
Ground Source Heat Pumps ◽  
Heat Pump System ◽  
Ground Source ◽  
Sewage Waste

Most Finnish residential buildings have been built before ventilation heat recovery options became mandatory. Exhaust air heat pumps are an effective way to reduce emissions, but they cannot cover all heating demand. Ground-source heat pumps can be designed to meet all loads, but they require corresponding amounts of space both above and below ground. This simulation study combines residential ventilation and sewage waste heat with a ground-source heat pump system to improve system sustainability and cost-effectiveness. A hybrid waste heat and ground-source heat pump system was shown to have 20% lower life cycle costs compared to a pure ground-source heat pump system. It also maintained sustainable ground temperature levels over the long term, while reducing above-ground space requirements by 95%.

A Techno-economic Analysis of Heat-Pump Entering Fluid Temperatures, and CO2 Emissions for Hybrid Ground Source Heat Pump Systems

2021 ◽  
Author(s):  
Hiep V. Nguyen ◽  
Ying Lam E. Law ◽  
Xiaoyan Zhou ◽  
Philip R. Walsh ◽  
Wey H. Leong ◽  
...  
Keyword(s):  
Natural Gas ◽  
Co2 Emissions ◽  
Heat Pump ◽  
Heat Pumps ◽  
Economic Effects ◽  
Fluid Temperature ◽  
Ground Source Heat Pump ◽  
Air Conditioner ◽  
Ground Source Heat Pumps ◽  
Ground Source

Hybrid ground-source heat pumps (GSHPs) that include a ground loop for the base heating and cooling needs, and an auxiliary system (natural gas boiler and electric air conditioner) for peak loads, are an economical and environmentally cleaner alternative to conventional systems. For a ground-source heat pump (GSHP) system, the choice of entering fluid temperature (EFT) to the heat pump plays a crucial role in determining system efficiency of and operating costs. To continue expanding the knowledge base of efficiently sizing GSHPs as a component of a hybrid system, this study explores the economic effects of choosing an EFT for a heat pump. In addition, system CO2 emissions are calculated and analyzed for a variety of building types. Using a computational approach to size hybrid GSHP systems recently published in [Alavy et al., Renewable Energy, 57 (2013) 404-412], the effects of optimizing EFT for a heat pump, and CO2 emissions were studied for a variety of commercial installations. In the present study, using ten buildings situated in Southern Ontario, Canada, by varying cooling and heating EFTs for a heat pump, savings ranging from 0.47% to 3.6% can be achieved compared to using a fixed EFT pairfor a heat pump. In addition, comparisons were made between the CO2 emissions of optimally sized (based on economic factors) hybrid GHSPs and those of non-hybridized GSHPs. Both the optimally-sized hybrid GHSPs, and the non-hybridized GSHPs significantly reduce CO2 emissions compared to the use of conventional natural gas/electrical systems. The additional environmental benefit of the non-hybridized GSHPs over that of the optimally-sized hybrid GSHPs was found to be negligible in most cases analyzed.

A Techno-economic Analysis of Heat-Pump Entering Fluid Temperatures, and CO2 Emissions for Hybrid Ground Source Heat Pump Systems

2021 ◽  
Author(s):  
Hiep V. Nguyen ◽  
Ying Lam E. Law ◽  
Xiaoyan Zhou ◽  
Philip R. Walsh ◽  
Wey H. Leong ◽  
...  
Keyword(s):  
Natural Gas ◽  
Co2 Emissions ◽  
Heat Pump ◽  
Heat Pumps ◽  
Economic Effects ◽  
Fluid Temperature ◽  
Ground Source Heat Pump ◽  
Air Conditioner ◽  
Ground Source Heat Pumps ◽  
Ground Source

Hybrid ground-source heat pumps (GSHPs) that include a ground loop for the base heating and cooling needs, and an auxiliary system (natural gas boiler and electric air conditioner) for peak loads, are an economical and environmentally cleaner alternative to conventional systems. For a ground-source heat pump (GSHP) system, the choice of entering fluid temperature (EFT) to the heat pump plays a crucial role in determining system efficiency of and operating costs. To continue expanding the knowledge base of efficiently sizing GSHPs as a component of a hybrid system, this study explores the economic effects of choosing an EFT for a heat pump. In addition, system CO2 emissions are calculated and analyzed for a variety of building types. Using a computational approach to size hybrid GSHP systems recently published in [Alavy et al., Renewable Energy, 57 (2013) 404-412], the effects of optimizing EFT for a heat pump, and CO2 emissions were studied for a variety of commercial installations. In the present study, using ten buildings situated in Southern Ontario, Canada, by varying cooling and heating EFTs for a heat pump, savings ranging from 0.47% to 3.6% can be achieved compared to using a fixed EFT pairfor a heat pump. In addition, comparisons were made between the CO2 emissions of optimally sized (based on economic factors) hybrid GHSPs and those of non-hybridized GSHPs. Both the optimally-sized hybrid GHSPs, and the non-hybridized GSHPs significantly reduce CO2 emissions compared to the use of conventional natural gas/electrical systems. The additional environmental benefit of the non-hybridized GSHPs over that of the optimally-sized hybrid GSHPs was found to be negligible in most cases analyzed.

Sign in / Sign up

Export Citation Format

Share Document