scholarly journals Energy Savings Resulting from Using a Near-Surface Earth-to-Air Heat Exchanger for Precooling in Hot Desert Climates

Energies ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 8044
Author(s):  
Ali Pakari ◽  
Saud Ghani
Keyword(s):  
Heat Exchanger ◽  
Energy Use ◽  
Energy Savings ◽  
Field Measurements ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Environmental Benefits ◽  
Cooling Systems ◽  
Near Surface ◽  
Space Cooling

Given the substantial energy use for space cooling in buildings, integrating energy-efficient and sustainable cooling systems into buildings has become increasingly more important. Even though the cooling potential of a near-surface earth-to-air heat exchanger (EAHE) with grass cover was demonstrated in previous studies, the energy savings and environmental benefits resulting from using the EAHE have not yet been quantified. Therefore, in this study, we quantify the energy savings resulting from using a near-surface earth-to-air heat exchanger (EAHE) with grass-covered ground as a precooling unit in hot desert climates. The outlet air conditions of the EAHE during 9 months of the year (March to November), where space cooling is required, are predicted using a 3D transient CFD model, which is validated against field measurements. The EAHE is fabricated from a 1 mm thick aluminum tube with a diameter of 0.15 m and a length of 21.5 m, buried 0.4 m deep. The results showed that the EAHE can cool ambient air by up to 8.5 °C at an air flow rate of 607 m3/h, corresponding to a cooling capacity of 1700 W and a COP of 17. The daily average cooling capacity of the EAHE is about 560 W for an average operation period of 15.1 h per day. When used as a precooling unit for conventional cooling systems, the highest estimated monthly energy savings is 115 kWh, and the estimated annual savings is 741 kWh.

scholarly journals Towards Sustainable Energy Retrofitting, a Simulation for Potential Energy Use Reduction in Residential Buildings in Palestine

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3876
Author(s):  
Sameh Monna ◽  
Adel Juaidi ◽  
Ramez Abdallah ◽  
Aiman Albatayneh ◽  
Patrick Dutournie ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Energy Use ◽  
Energy Savings ◽  
Residential Buildings ◽  
Residential Building ◽  
Simulation Models ◽  
Water Heating ◽  
Heating And Cooling ◽  
Space Cooling ◽  
Cooling Loads

Since buildings are one of the major contributors to global warming, efforts should be intensified to make them more energy-efficient, particularly existing buildings. This research intends to analyze the energy savings from a suggested retrofitting program using energy simulation for typical existing residential buildings. For the assessment of the energy retrofitting program using computer simulation, the most commonly utilized residential building types were selected. The energy consumption of those selected residential buildings was assessed, and a baseline for evaluating energy retrofitting was established. Three levels of retrofitting programs were implemented. These levels were ordered by cost, with the first level being the least costly and the third level is the most expensive. The simulation models were created for two different types of buildings in three different climatic zones in Palestine. The findings suggest that water heating, space heating, space cooling, and electric lighting are the highest energy consumers in ordinary houses. Level one measures resulted in a 19–24 percent decrease in energy consumption due to reduced heating and cooling loads. The use of a combination of levels one and two resulted in a decrease of energy consumption for heating, cooling, and lighting by 50–57%. The use of the three levels resulted in a decrease of 71–80% in total energy usage for heating, cooling, lighting, water heating, and air conditioning.

scholarly journals Experimental Study to Performance Improvement of Vapor Compression Cooling System Integrated Direct Evaporative Cooler and Condenser

2018 ◽  
Vol 215 ◽  
pp. 01017
Author(s):  
Arfidian Rachman ◽  
Lisa Nesti
Keyword(s):  
Energy Use ◽  
Cooling System ◽  
Electricity Consumption ◽  
Weather Condition ◽  
Heat Removal ◽  
Cooling Capacity ◽  
Cooling Power ◽  
Cooling Systems ◽  
Evaporative Cooler ◽  
And Performance

For areas with very hot and humid weather condition increased latent and sensible load are a major problem in cooling systems that will increase compressor work so that electricity consumption will also increase. Combined condenser with direct evaporate cooling will increase the heat removal process by using an evaporative cooler effect that will increase the efficiency of energy use. This paper presents the study of the use of evaporator cooling and condenser. This paper mainly calculated energy consumption in steam compression cooling systems and related problems. From the results of this study, the use of condensers with evaporative cooling, power consumption can be reduced to 46% and performance coefficient (COP) can be increased by about 12%, with 1,2 kW cooling capacity.

scholarly journals Innovative Turbine Intake Air Cooling Systems and Their Rational Designing

Energies ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 6201
Author(s):  
Andrii Radchenko ◽  
Eugeniy Trushliakov ◽  
Krzysztof Kosowski ◽  
Dariusz Mikielewicz ◽  
Mykola Radchenko
Keyword(s):  
Gas Turbines ◽  
Maximum Rate ◽  
Cooling System ◽  
Ambient Air ◽  
Cooling Capacity ◽  
Climatic Conditions ◽  
Air Cooling ◽  
Thermal Loads ◽  
Cooling Systems ◽  
Air Cooling System

The efficiency of cooling ambient air at the inlet of gas turbines in temperate climatic conditions was analyzed and reserves for its enhancing through deep cooling were revealed. A method of logical analysis of the actual operation efficiency of turbine intake air cooling systems in real varying environment, supplemented by the simplest numerical simulation was used to synthesize new solutions. As a result, a novel trend in engine intake air cooling to 7 or 10 °C in temperate climatic conditions by two-stage cooling in chillers of combined type, providing an annual fuel saving of practically 50%, surpasses its value gained due to traditional air cooling to about 15 °C in absorption lithium-bromide chiller of a simple cycle, and is proposed. On analyzing the actual efficiency of turbine intake air cooling system, the current changes in thermal loads on the system in response to varying ambient air parameters were taken into account and annual fuel reduction was considered to be a primary criterion, as an example. The improved methodology of the engine intake air cooling system designing based on the annual effect due to cooling was developed. It involves determining the optimal value of cooling capacity, providing the minimum system sizes at maximum rate of annual effect increment, and its rational value, providing a close to maximum annual effect without system oversizing at the second maximum rate of annual effect increment within the range beyond the first maximum rate. The rational value of design cooling capacity provides practically the maximum annual fuel saving but with the sizes of cooling systems reduced by 15 to 20% due to the correspondingly reduced design cooling capacity of the systems as compared with their values defined by traditional designing focused to cover current peaked short-term thermal loads. The optimal value of cooling capacity providing the minimum sizes of cooling system is very reasonable for applying the energy saving technologies, for instance, based on the thermal storage with accumulating excessive (not consumed) cooling capacities at lowered current thermal loads to cover the peak loads. The application of developed methodology enables revealing the thermal potential for enhancing the efficiency of any combustion engine (gas turbines and engines, internal combustion engines, etc.).

scholarly journals A Review of Underground Soil and Night Sky as Passive Heat Sink: Design Configurations and Models

Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2941 ◽  
Author(s):  
Rachana Vidhi
Keyword(s):  
Heat Transfer ◽  
Energy Consumption ◽  
Heat Sink ◽  
Heat Exchangers ◽  
Energy Use ◽  
Ambient Air ◽  
Radiative Cooling ◽  
Cooling Systems ◽  
Heating And Cooling ◽  
Night Sky

Energy consumption for heating and cooling constitute the majority of the energy use for building loads. Using passive cooling systems to reduce the energy consumption or to make the process more efficient can be very beneficial. Ground coupled heat exchangers and night sky radiative cooling systems have been used for centuries to achieve cooling and ice making. Ground coupled heat exchangers use the temperature difference between underground soil and ambient air or water for heat transfer between the soil and the fluid passing through buried pipes. Night sky radiative cooling takes advantage of the night sky as the coldest heat sink available for heat transfer with any surface. Use of these simple designs with the modern cooling/heating systems has the potential for a major impact on the heating and cooling needs. This review paper describes the various designs, configurations and applications of these systems as well as determining the parameters that impact their performance.

Energy Savings on Automotive Air Conditioner Using Liquid-Suction Heat Exchanger Subcooler

2014 ◽  
Vol 554 ◽  
pp. 256-260 ◽  
Author(s):  
Budi Mursanto Wahyu ◽  
Kasni Sumeru ◽  
Abdul Aziz Azhar ◽  
Nasution Henry
Keyword(s):  
Heat Exchanger ◽  
Numerical Analysis ◽  
Vapor Phase ◽  
Energy Savings ◽  
Cooling Capacity ◽  
Air Conditioner ◽  
Condenser Temperature ◽  
Refrigeration Capacity

The present study describes a numerical analysis of the effect of subcooling using liquid-suction heat exchanger (LSHX) on the performance of automotive air conditioner. Besides increasing the cooling capacity, subcooling using LSHX also generates superheating in the suction of the compressor, where the superheating ensures only vapor phase of refrigerant entering the compressor suction and reduces the risk of damage to the compressor. The results show that the refrigeration capacity improvements and COP improvements up to 11.86% and 5.64%, respectively, for the subcooling of 1 K to 10 K and the condenser temperature of 40°C to 50°C.

scholarly journals Empirical and Numerical Analysis of an Opaque Ventilated Facade with Windows Openings under Mediterranean Climate Conditions

Mathematics ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 163
Author(s):  
Carlos-Antonio Domínguez-Torres ◽  
Ángel Luis León-Rodríguez ◽  
Rafael Suárez ◽  
Antonio Domínguez-Delgado
Keyword(s):  
Energy Consumption ◽  
Energy Use ◽  
Energy Savings ◽  
Field Measurements ◽  
Energy Performance ◽  
Total Energy Consumption ◽  
Building Stock ◽  
Climate Conditions ◽  
Ventilated Facade ◽  
Indoor Comfort

In recent years, there has been growing concern regarding energy efficiency in the building sector with energy requirements increasing worldwide and now responsible for about 40% of final energy consumption in Europe. Previous research has shown that ventilated façades help to reduce energy use when cooling buildings in hot and temperate climates. Of the different ventilated façade configurations reported in the literature, the configuration of ventilated façade with window rarely has been studied, and its 3D thermodynamic behavior is deserving of further analysis and modeling. This paper examines the thermal behavior of an opaque ventilated façade with a window, in experimentally and numerical terms and its impact in energy savings to get indoor comfort. Field measurements were conducted during the winter, spring and summer seasons of 2021 using outdoor full scale test cells located in Seville (southern Spain). The modeling of the ventilated façade was carried out using a three-dimensional approach taking into account the 3D behavior of the air flow in the air cavity due to the presence of the window. The validation and comparison process using experimental data showed that the proposed model provided good results from quantitative and qualitative point of view. The reduction of the heat flux was assessed by comparing the energy performance of a ventilated façade with that of an unventilated façade. Both experimental and numerical results showed that the ventilated façade provided a reduction in annual total energy consumption when compared to the unventilated façade, being compensated the winter energy penalization by the summer energy savings. This reduction is about 21% for the whole typical climatic year showing the ability of the opaque ventilated façade studied to reduce energy consumption to insure indoor comfort, making its suitable for use in retrofitting the energy-obsolete building stock built in Spain in the middle decades of the 20 century.

Evaluating Thermal Performance and Energy Conservation Potential of Hybrid Earth Air Tunnel Heat Exchanger in Hot and Dry Climate—In Situ Measurement

2013 ◽  
Vol 5 (3) ◽  
Author(s):  
Rohit Misra ◽  
Vikas Bansal ◽  
Ghanshyam Das Agarwal ◽  
Jyotirmay Mathur ◽  
Tarun Aseri
Keyword(s):  
Energy Consumption ◽  
Heat Exchanger ◽  
Energy Conservation ◽  
Thermal Performance ◽  
Cooling System ◽  
Ambient Air ◽  
Passive Cooling ◽  
Air Conditioner ◽  
Cooling Systems ◽  
Active Cooling

Earth air tunnel heat exchanger is a passive cooling device with advantageous feature to reduce energy consumption in buildings. Curtailing the electricity consumption of conventional vapor compression system based air-conditioner is a major concern especially in area with hot and dry weather conditions. The performance of conventional air-conditioners can substantially be enhanced by coupling these active cooling systems with passive cooling systems. In the present research, the thermal performance and energy conservation potential of hybrid cooling system has been investigated experimentally. An attempt has been made to enhance the thermal performance of active cooling system by coupling it with earth air tunnel heat exchanger (EATHE) in two different hybrid modes. The air which comes out of EATHE is relatively cooler than the ambient air and therefore can be used either for cooling the condenser tubes of a conventional window type air-conditioner or supplying it directly to the room being conditioned. The energy consumption of conventional 1.5TR window type air conditioner is found to be reduced by 16.11% when cold air from EATHE is completely used for condenser cooling.

Energy Savings in Cloud Computing: Conventional Versus Cloud Energy Use

2016 ◽  
Author(s):  
Daniel Comperchio
Keyword(s):  
Cloud Computing ◽  
Energy Use ◽  
Data Centers ◽  
Energy Savings ◽  
Cloud Services ◽  
Cloud Provider ◽  
Cooling Systems ◽  
And Storage

With the explosive growth of demand for cloud services in the last few years, providers are building more and larger data centers almost continuously. As the scale of the facilities increases, more emphasis is placed on homogenizing equipment, streamlining operations, and focusing intensely on driving higher levels of efficiency in both the compute infrastructure and physical power and cooling systems. For customers, this translates to lower costs for the services provided, but looking deeper uncovers a larger set of benefits. Beyond the savings associated with licensing, maintaining, and refreshing servers and storage equipment, companies looking at migrating to a cloud provider will see a tremendous operating savings by significantly reducing the energy use of their workloads.

Analysis of a Solar Space Cooling System Using Liquid Desiccants

1990 ◽  
Vol 112 (4) ◽  
pp. 246-250 ◽  
Author(s):  
P. Gandhidasan
Keyword(s):  
Heat Exchanger ◽  
Cooling System ◽  
Cooling Water ◽  
Ambient Air ◽  
Solution Concentration ◽  
Simple Expression ◽  
Ventilation Mode ◽  
Cooling Water Temperature ◽  
System A ◽  
Space Cooling

For tropical countries, solar space cooling is an attractive proposition. Dehumidification of air in hot, humid climates is almost as important as cooling. Removal of moisture from the air is much easier to achieve than cooling the air. The proposed cooling system operates on the ventilation mode. The ambient air is dehumidified using liquid desiccants followed by adiabatic evaporative cooling. The desiccant soon becomes saturated with the water extracted from the air and can be regenerated by using solar energy. For this system, a simple expression is derived in this paper to predict the amount of heat removed from the space to be conditioned in terms of known initial parameters through a simplified vapor pressure correlation and effectiveness of the dehumidifier and the heat exchanger. The effect of ambient air conditions, solution concentration, the cooling water temperature and the effectiveness of the dehumidifier and the heat exchanger on the performance of the cooling system are also discussed in this paper.

scholarly journals Impact of a building shape factor on space cooling energy performance in the green roof concept implementation

2018 ◽  
Vol 22 (1 Part B) ◽  
pp. 687-698 ◽  
Author(s):  
Marija Stamenkovic ◽  
Mirjana Miletic ◽  
Saja Kosanovic ◽  
Goran Vuckovic ◽  
Srdjan Glisovic
Keyword(s):  
Shape Factor ◽  
Energy Savings ◽  
Green Roof ◽  
Green Roofs ◽  
Energy Performance ◽  
Environmental Benefits ◽  
Existing Buildings ◽  
Building Shape ◽  
Building Models ◽  
Space Cooling

The reduction of energy demand for space cooling requires adequate solutions at building and built environment scales in order to achieve sustainability goals. Since many existing buildings have inadequate envelopes for reducing heat gains in summer and heat losses in winter, environmentally friendly renovation techniques have to be considered. The roofs of existing buildings were identified as a field of intervention which could contribute to providing both energy savings and environmental benefits. The aim of the paper was to evaluate the contribution of green roofs to energy savings for space cooling depending on the building shape factor. Two groups of building models, with vertical and horizontal expansions, were analysed. The comparative analyses of the building models with conventional and green roofs showed small reduction of energy consumption less than 1% in case of well-insulated roofs with the addition of the extensive green roof. The comparison of different building models with green roofs of the same volume, which is in this case the same cooling area, indicated a more effective solution for green roofs implementation with the aim to improve energy performances of existing buildings using this passive design technique.

Sign in / Sign up

Export Citation Format

Share Document