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.

Buildings

2017 ◽  
Author(s):  
Peter Rez
Keyword(s):  
Heat Transfer ◽  
Heat Pump ◽  
Energy Efficient ◽  
Energy Use ◽  
Fossil Fuel ◽  
Local Climate ◽  
Heating And Cooling ◽  
The Difference ◽  
As If

Most of the energy used by buildings goes into heating and cooling. For small buildings, such as houses, heat transfer by conduction through the sides is as much as, if not greater than, the heat transfer from air exchanges with the outside. For large buildings, such as offices and factories, the greater volume-to-surface ratio means that air exchanges are more significant. Lights, people and equipment can make significant contributions. Since the energy used depends on the difference in temperature between the inside and the outside, local climate is the most important factor that determines energy use. If heating is required, it is usually more efficient to use a heat pump than to directly burn a fossil fuel. Using diffuse daylight is always more energy efficient than lighting up a room with artificial lights, although this will set a limit on the size of buildings.

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 Analysis and Comparison of Some Low-Temperature Heat Sources for Heat Pumps

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1853 ◽  
Author(s):  
Pavel Neuberger ◽  
Radomír Adamovský
Keyword(s):  
Heat Transfer ◽  
Low Temperature ◽  
Heat Source ◽  
Heat Pump ◽  
Heat Exchangers ◽  
Ambient Air ◽  
Heat Transfer Fluid ◽  
Heat Sources ◽  
Ground Heat Exchangers ◽  
Temperature Heat

The efficiency of a heat pump energy system is significantly influenced by its low-temperature heat source. This paper presents the results of operational monitoring, analysis and comparison of heat transfer fluid temperatures, outputs and extracted energies at the most widely used low temperature heat sources within 218 days of a heating period. The monitoring involved horizontal ground heat exchangers (HGHEs) of linear and Slinky type, vertical ground heat exchangers (VGHEs) with single and double U-tube exchanger as well as the ambient air. The results of the verification indicated that it was not possible to specify clearly the most advantageous low-temperature heat source that meets the requirements of the efficiency of the heat pump operation. The highest average heat transfer fluid temperatures were achieved at linear HGHE (8.13 ± 4.50 °C) and double U-tube VGHE (8.13 ± 3.12 °C). The highest average specific heat output 59.97 ± 41.80 W/m2 and specific energy extracted from the ground mass 2723.40 ± 1785.58 kJ/m2·day were recorded at single U-tube VGHE. The lowest thermal resistance value of 0.07 K·m2/W, specifying the efficiency of the heat transfer process between the ground mass and the heat transfer fluid, was monitored at linear HGHE. The use of ambient air as a low-temperature heat pump source was considered to be the least advantageous in terms of its temperature parameters.

scholarly journals A Complementary Approach to Traditional Energy Balances for Assessing Energy Efficiency Measures in Final Uses: The Case of Space Heating and Cooling in Argentina

2020 ◽  
Vol 12 (16) ◽  
pp. 6563
Author(s):  
Roque G Stagnitta ◽  
Matteo V Rocco ◽  
Emanuela Colombo
Keyword(s):  
Energy Consumption ◽  
Energy Use ◽  
Primary Energy ◽  
Embodied Energy ◽  
Space Heating ◽  
Output Analysis ◽  
Final Energy ◽  
Heating And Cooling ◽  
Energy Balances ◽  
The Impact

Energy balances have been historically conceived based on a supply-side perspective, providing neither detailed information about energy conversion into useful services nor the effects that may be induced by the application of policies in other sectors to energy consumption. This article proposes an approach to a thorough assessment of the impact of efficiency policies on final energy uses, focusing on residential space heating and cooling, and capable of: (1) quantifying final useful services provided and (2) accounting for the global impact of efficiency policies on final energy use, taking advantage of Input–Output analysis. This approach is applied in five cities of Argentina. Firstly, the quantity of energy service provided (i.e., level of thermal comfort) for each city is evaluated and compared with the defined target. It is found out that heating comfort is guaranteed approximately as established, whereas in the cooling case the provision is twice the established level. Secondly, primary energy consumption of heating and cooling services is evaluated before and after different efficiency improvement policies. The results show that the major primary energy saving (52%) is obtained from the upgrading appliances scenario and reflect the importance of accounting for embodied energy in goods and services involved in interventions.

scholarly journals Economic justification of the choice of the thermal protection of buildings

2018 ◽  
Vol 196 ◽  
pp. 04078
Author(s):  
Elena Malyavina ◽  
Anastasya Frolova
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Specific Heat ◽  
Thermal Protection ◽  
Transfer Resistance ◽  
Cooling Systems ◽  
Heating And Cooling ◽  
Heat Protection ◽  
The Cost

A large number of factors influence the economically feasible heat transfer resistance of the building enclosing structures. First of all, it is the cost of insulation and heat for the building heating in the cold season. As shown by studies, it is not enough for air-conditioned buildings. The result depends on the mode of the building operation in time and the heat load on the heating and cooling systems. Therefore, in addition to these significant factors of economic feasibility of the thermal protection level, there are the cost of electricity for the production of cold for cooling the building, the cost of the building heating and cooling systems and the cost of connection to power supply networks. The got result is important to convey to the professional community in a clear and compact form. In the present work the buildings of administrative and office purpose are considered, the working day of which lasts from 9-00 to 18-00 hours with different specific heat supply from 0 to 80 W/m2 on the estimated area during working hours. Generalization of the research results is made on the basis of specific heat protection characteristics of the building, which is a product of the overall heat transfer coefficient of the building and the compactness coefficient. The total heat transfer coefficient of the building characterizes the heat losses and the heat inflows to the building through the enclosing structures, and the compactness coefficient can serve as an indicator of the surface area of the building, which is covered with insulation. For these buildings provision has been made for identification of the areas of the total discounted cost combination for all of the above components and the specific heat protection characteristics of the building relating to the feasibility of the specified level of the thermal protection.

scholarly journals Analysis of the Effect of Using External Venetian Blinds on the Thermal Comfort of Users of Highly Glazed Office Rooms in a Transition Season of Temperate Climate—Case Study

Energies ◽  
2019 ◽  
Vol 13 (1) ◽  
pp. 81 ◽  
Author(s):  
Małgorzata Fedorczak-Cisak ◽  
Katarzyna Nowak ◽  
Marcin Furtak
Keyword(s):  
Energy Consumption ◽  
Thermal Comfort ◽  
Ambient Air ◽  
Temperate Climate ◽  
Cooling Systems ◽  
Clothing Insulation ◽  
Transition Season ◽  
Venetian Blinds ◽  
Research Task ◽  
Office Rooms

Improving the energy efficiency of buildings is among the most urgent social development tasks due to the scale of energy consumption in this industry. At the same time, it is essential to meet high requirements for indoor environmental quality and thermal comfort. The issue of overheating is most often analysed in summer but it also occurs in transition seasons, when the cooling systems do not operate. The paper attempts to evaluate the effectiveness of external mobile shading elements on the microclimate of rooms with large glazed areas in the transition season. Passive solutions, such as shading elements, which limit the increase of indoor temperature, do not always allow the acquisition and maintenance of comfortable solutions for the duration of the season, as demonstrated by the authors. Temporary cooling of the rooms may be necessary to maintain comfortable conditions for the users, or other solutions should be devised to improve comfort (e.g., reduction of clothing insulation characteristics). The novelty of the study consists in the analysis of comfort in a “nearly zero energy consumption” building (NZEB) during a period not analyzed by other scientists. This is a transition period during which heating/cooling systems do not operate. The research task set by the authors involved the assessment of the possibility to reduce office space overheating in the transition season (spring) by using external shading equipment in rooms with large glazed areas. An additional research task aimed at checking the extent to which user behaviour, such as reduction in clothing insulation characteristics, can improve comfort in overheated rooms. The results of the tests reveal that the difference in the ambient air temperature between a room with external venetian blinds and an identical room with no venetian blinds in the transition season, i.e., from 27 March to 6 April 2017, ranged from 12.3 to 2.1 °C. The use of a shading system (external venetian blinds positioned at an angle of 45°) reduced the number of discomfort hours by 92% (during working hours) compared to the room without external venetian blinds. A reduction in the thermal insulation of the clothes worn by people working in the room with no venetian blinds helped to reduce the number of discomfort hours by 31%.

COMPARISON OF COOLING AND HEATING REQUIREMENTS BETWEEN BRICK VENEER AND FIBRO CEMENT WALLING SYSTEM

2017 ◽  
Vol 4 (1) ◽  
Author(s):  
Swapan Saha ◽  
Dharma Hagare ◽  
Jiaqi Zhou ◽  
Md Kamrul Hassan
Keyword(s):  
Energy Consumption ◽  
Energy Cost ◽  
Energy Use ◽  
Net Present Value ◽  
Space Heating ◽  
Heating And Cooling ◽  
Space Cooling ◽  
Brick Veneer ◽  
Save Energy ◽  
Modern House

Space cooling and heating in residential sector is significant contributor to energy consumption in Australia. Therefore, it is important to reduce the cooling and heating requirements. The selection of a good walling system helps to save energy by homes. This research compared the thermal efficiency of a modern house (constructed using brick veneer walls with concrete floor slab) with an old house (constructed using fibro cement walls raised timber floor) using the AccuRate simulation tool. A standard house with two living rooms, one kitchen, one laundry and four bedrooms are simulated in a Sydney Suburb in Australia. It was found that modern house showed lower inside temperature variation than the old house all year around. The results also showed that the modern house has a lower energy consumption for space heating and cooling than the old house. The annual energy use for space heating and cooling in both the modern house and old house were 5197 kWh and 15,712 kWh respectively. Moreover, the annual energy costs were found to be $1,403 and $4,242 respectively for modern and old houses. The modern brick veneer house saved about 33 % of energy compared to old old house. When the net present value of the energy cost for f both houses over 50 years is computed, the energy cost of modern house was found to be $25,629 while it of old house is was $77,488 for the old house.

scholarly journals Analysis of heating and cooling periods in Budapest using station data

Időjárás ◽  
2021 ◽  
Vol 125 (3) ◽  
pp. 431-448
Author(s):  
Csenge Dian ◽  
Attila Talamon ◽  
Rita Pongrácz ◽  
Judit Bartholy
Keyword(s):  
Energy Use ◽  
Transitional Period ◽  
Design Parameters ◽  
Data Series ◽  
Total Energy Consumption ◽  
Regional Warming ◽  
Cooling Systems ◽  
Cooling Period ◽  
Heating And Cooling ◽  
The One

The built environment has a very complex role in cities. On the one hand, various urban climatological phenomena are caused and influenced by buildings (e.g., urban heat island effect, local wind conditions, air pollution). On the other hand, buildings are important contributors to energy use via heating and cooling, e.g. they account for about 40% of total energy consumption on average in Europe. Daily average outdoor temperature is taken into account to design the heating and cooling systems of residential, commercial, or office buildings. That is why we analyzed the available temperature time series of the capital of Hungary, Budapest for the period between 1901 and 2019. The aims of this study are (i) to investigate the changes in temperature data series that influence building energy design parameters, (ii) to analyze the heating and cooling periods in the last 119 years based on different definitions, and (iii) to define a third (transitional) period between the heating and cooling periods. Based on the results, it can be concluded that the variability of warm days is smaller than that of cold days, consequently, the optimal design of heating systems is a greater challenge compared to cooling systems. Furthermore, the length of the temperature-based heating period decreased substantially, while the length of the cooling period increased as a consequence of overall regional warming.

scholarly journals Full IoT Lora School Building Management System

2019 ◽  
Author(s):  
Bruno Mataloto ◽  
Joao C. Ferreira ◽  
Nuno Cruz
Keyword(s):  
Energy Consumption ◽  
Low Cost ◽  
Development Phase ◽  
Total Energy Consumption ◽  
Cooling Systems ◽  
Flexible Approach ◽  
Heating And Cooling ◽  
Building Management ◽  
Building Management System ◽  
Communication Board

In this research paper we describe the development phase of a low-cost LoRa IoT solution applied to a kindergarten school with three years results. A set of sensors solution was developed in a LoRa communication board, battery powered, providing a simplified setup process. These sensors were used in order to measure temperature, humidity, luminosity, air quality and presence. Also, energy monitor solutions were integrated. The acquired data is transmitted and analysed for knowledge extraction, identifying savings and other related KPIs. From data, automatic saving actions were performed towards heating and cooling systems, lighting and a set of if-then actions were developed for automatic cost-saving actions, based on infrared signals to heating/cooling systems using some procedure of external command devices. This approach avoids the usage of proprietary vendor solutions in a flexible approach that can easily be deployed to any building facility. This is an important achievement since most of the building consumption is based on heating and cooling systems. In a three years test of the solution, the total energy consumption savings surpassed 20%

scholarly journals Performance Improvement of a Forced Draught Cooling Tower Using a Vortex Generator

CFD letters ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 45-57
Author(s):  
Dan Mugisidi ◽  
Oktarina Heriyani ◽  
Pancatatva Hesti Gunawan ◽  
Dwi Apriani
Keyword(s):  
Heat Transfer ◽  
Energy Consumption ◽  
Water Temperature ◽  
Production Process ◽  
Performance Improvement ◽  
Cooling Tower ◽  
Vortex Generator ◽  
Vortex Generators ◽  
Cooling Systems ◽  
Air Discharge

Cooling systems using colling towers are often an important element in a production process and always involve water or energy consumption. Therefore, increasing the efficiency of the colling tower will reduce water and / or energy consumption. In order to increase the efficiency of colling tower energy consumption, the most studied part is the fills, where heat transfer occurs. However, there are no studies on the use of vortex generators in colling tower fills. Hence the aim of this study was to evaluate the performance improvement in a forced draught cooling tower using a vortex generator. It was conducted on a laboratory scale using single fill as a trial medium. The fill was made of 3-mm acrylic with dimensions of 30 × 30 × 1950 mm. A three-unit vortex generator was placed inside the fill. The rectangular vortex generator was made of 0.5-mm thick aluminium and had a size of 50 × 10 mm. Data were retrieved for the fills with and without a vortex generator. Water and air discharge of 1 L/minute and an inlet water temperature of 60°C were maintained. The results indicated that the effectiveness of the fill with a vortex generator was increased by 90.72% compared to the fill without a vortex generator.

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