Energy Saving Potential of a Combined Solar and Natural Gas-Assisted Vapor Absorption Building Cooling System

2018 ◽  
Vol 141 (1) ◽  
Author(s):  
Gaurav Singh ◽  
Ranjan Das
Keyword(s):  
Natural Gas ◽  
Energy Savings ◽  
Cooling System ◽  
Electric Energy ◽  
High Capacity ◽  
Climatic Conditions ◽  
Comfort Level ◽  
Coefficient Of Performance ◽  
Electric Energy Consumption ◽  
Vapor Absorption

A building energy simulation study is carried out to analyze the performance of a triple-hybrid single-effect vapor absorption cooling system (VACS) operated by solar, natural gas, and auxiliary electricity-based cogeneration. A high capacity small office building subjected to different climatic conditions is considered. The system is designed to continuously maintain a specified building comfort level throughout the year under diverse environmental conditions. Simulations are done at different generator temperatures to investigate the performance in terms of total annual electric energy consumption, heating energy, and the coefficient of performance (COP). The performance of the present VACS is compared with the conventional compression-based system, which demonstrates the electric energy and cost saving potentials of the proposed VACS. Simulation outcomes are well-validated against benchmark data from national renewable energy laboratory and energy conservation building code. Interestingly, it is found that beyond a certain collector area, surplus energy savings can be acquired with the present triple-hybrid VACS as compared to the compression-based cooling. Results also show that COP of the simulated system is in line with experimental values available in the literature. Finally, recommendations are given to operate the complete system on solar and biomass resources, which provide encouraging opportunity for agriculture-based countries.

A Novel Design of Triple-Hybrid Absorption Radiant Building Cooling System With Desiccant Dehumidification

2019 ◽  
Vol 141 (7) ◽  
Author(s):  
Gaurav Singh ◽  
Ranjan Das
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Cooling System ◽  
Electric Energy ◽  
Electric Heater ◽  
Operational Strategies ◽  
Electric Energy Consumption ◽  
Radiant Cooling ◽  
Building Cooling ◽  
Novel Design

In air-conditioning, strategy of decoupling cooling and ventilation tasks has stimulated considerable interest in radiant cooling systems with dedicated outdoor air system (DOAS). In view of this, current paper presents a simulation study to describe energy saving potential of a solar, biogas, and electric heater powered hybrid vapor absorption chiller (VAC) based radiant cooling system with desiccant-coupled DOAS. A medium office building under warm and humid climatic condition is considered. To investigate the system under different operational strategies, energyplus simulations are done. In this study, a novel design involving solar collectors and biogas fired boiler is proposed for VAC and desiccant regeneration. Three systems are compared in terms of total electric energy consumption: conventional vapor compression chiller (VCC) based radiant cooling system with conventional VCC-DOAS, hybrid VAC-based radiant cooling system with conventional VCC-DOAS, and hybrid VAC-based radiant cooling system with desiccant-assisted VCC-DOAS. The hybrid VAC radiant cooling system and desiccant-assisted VCC-DOAS yields in 9.1% lesser energy consumption than that of the VAC radiant cooling system with conventional VCC-DOAS. Results also show that up to 13.2% energy savings can be ensured through triple-hybrid VAC radiant cooling system and desiccant-assisted VCC-DOAS as compared to that of the conventional VCC-based radiant system. The return on investment is observed to be 14.59 yr for the proposed system.

scholarly journals Desiccant cooling as an alternative to traditional air conditioners in green cooling technology

2019 ◽  
pp. 01-13
Author(s):  
Jani DB
Keyword(s):  
Air Conditioning ◽  
Energy Savings ◽  
Cooling System ◽  
Green Building ◽  
Climatic Conditions ◽  
Coefficient Of Performance ◽  
Low Grade ◽  
Vapor Compression ◽  
Cooling Technology ◽  
Air Conditioning Systems

Desiccant-based dehumidification and air conditioning systems are considered as an energy efficient alternative to traditional vapor compression based air-conditioning systems for green building cooling technology especially in tropical hot and humid ambient climates. It is a novel green cooling technology that makes use of low-grade heat for building air conditioning. It is seen that the desiccant based dehumidification and cooling can efficiently provide comfort conditions in subtropical and especially hot and humid tropical climates. The desiccant integrated novel cooling system has a significant higher coefficient of performance compared to the conventional vapor compression system resulting to substantial electrical energy savings during the summer season by use of renewable solar energy, which also resulted in to major reduction in CO2 emissions. Therefore, these results demonstrate that there is a good potential in desiccant-based dehumidification and cooling system for energy and carbon savings while carry out building air-conditioning. Through a literature review, the feasibility of the desiccant assisted air conditioning in hot and humid climatic conditions is proven and the advantages it can offer in terms energy and cost savings are underscored. Keywords: Air-conditioning; Desiccant cooling; Dehumidification; Green cooling; Thermal comfort

Energy Saving Assessment of Triple-Hybrid Vapor Absorption Building Cooling System Under Hot-Dry Climate

2021 ◽  
Author(s):  
Gaurav Singh ◽  
Ranjan Das
Keyword(s):  
Heat Input ◽  
Air Conditioning ◽  
Energy Savings ◽  
Cooling System ◽  
Electrical Energy ◽  
Coefficient Of Performance ◽  
Absorption System ◽  
Vapor Absorption ◽  
Thermally Driven ◽  
Building Cooling

Abstract Thermally driven vapor absorption-based air-conditioning systems possess many advantages over the compression based systems. However, intermittent availability of input resources affects the operation of these absorption systems which causes discontinuous working. This study aims at examining the electrical and thermodynamic performance of a triple-hybrid vapor absorption-assisted air-conditioning system against a conventional system with the aid of EnergyPlus simulations for a small office building. The outside weather is subjected to hot-dry climatic condition. The heat input source includes biomass and solar energy-based resources. Auxiliary heat input is also used to ensure smooth operation. The performance of the absorption system is assessed at different generator temperature (70 °C–80 °C) and solar collector area (400 m2–500 m2). The results show that, by using absorption-based systems, a maximum of 34.1% electrical energy savings can be ensured at 500 m2 collector area with 70 °C generator temperature. The coefficient of performance of the absorption system escalates from 0.50 to 0.52 by increasing the generator temperature form 70 °C to 80 °C. Under the condition of 70 °C generator temperature and 500 m2 collector area, the absorption system can be made fully renewable energy dependent.

Measurements of electric energy consumption in a low energy building in Slovak climatic conditions

2012 ◽  
Vol 7 (3) ◽  
pp. 23-32 ◽  
Author(s):  
Miloslav Bagoňa ◽  
Dušan Katunský ◽  
Martin Lopušniak ◽  
Marián Vertaľ
Keyword(s):  
Energy Consumption ◽  
Electric Energy ◽  
Climatic Conditions ◽  
Low Energy ◽  
Electric Energy Consumption

scholarly journals AUDIT ENERGI PADA SEBUAH HOTEL

2012 ◽  
Vol 16 (3) ◽  
pp. 131
Author(s):  
Didik Ariwibowo
Keyword(s):  
Energy Consumption ◽  
Air Conditioning ◽  
Energy Savings ◽  
Electric Energy ◽  
Electrical Energy ◽  
Hot Water ◽  
Electrical Energy Consumption ◽  
Energy Audit ◽  
Electric Energy Consumption ◽  
Pumping System

Didik Ariwibowo, in this paper explain that energy audit activities conducted through several phases, namely: the initial audit, detailed audit, analysis of energy savings opportunities, and the proposed energy savings. Total energy consumed consists of electrical energy, fuel, and materials in this case is water. Electrical energy consumption data obtained from payment of electricity accounts for a year while consumption of fuel and water obtained from the payment of material procurement. From the calculation data, IKE hotels accounted for 420.867 kWh/m2.tahun, while the IKE standards for the hotel is 300 kWh/m2.tahun. Thus, IKE hotel included categorized wasteful in energy usage. The largest energy consumption on electric energy consumption. Largest electric energy consumption is on the air conditioning (AC-air conditioning) that is equal to 71.3%, and lighting and electrical equipment at 27.28%, and hot water supply system by 4.44%. Electrical energy consumption in AC looks very big. Ministry of Energy and Mineral Resources of the statutes, the profile of energy use by air conditioning at the hotel by 48.5%. With these considerations in the AC target for audit detail as the next phase of activity. The results of a detailed audit analysis to find an air conditioning system energy savings opportunities in pumping systems. Recommendations on these savings is the integration of automation on the pumping system and fan coil units (FCU). The principle of energy conservation in the pumping system is by installing variable speed drives (VSD) pump drive motor to adjust speed according to load on the FCU. Load variations FCU provide input on the VSD pumps to match. Adaptation is predicted pump can save electricity consumption up to 65.7%. Keywords: energy audit, IKE, AC

Performance of Heat Pump Water Heater (HPWH) Systems and Their Impacts on Electric Utility Loads

2010 ◽  
Vol 2 (2) ◽  
Author(s):  
Yahya I. Sharaf-Eldeen
Keyword(s):  
Heat Pump ◽  
Energy Savings ◽  
Electric Energy ◽  
Cost Savings ◽  
Electric Heating ◽  
Electric Utility ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Water Heaters ◽  
Peak Loads

This work involves measurements, analyses, and evaluation of performance of air-source heat pump water heaters (HPWHs), and their impacts on electric utility loads. Two add-on, heat pumps (HPs) rated at 7000 BTU/h (2.051 kW) and 12,000 BTU/h (3.517 kW) were utilized. The HPs were retrofitted to two 50 gal (189.3 l) electric water heaters (EWHs) with their electric heating elements removed. A third standard EWH was used for comparison. The testing setups were fully instrumented for measurements of all pertinent parameters, including inlet and outlet water temperatures, inlet and outlet air temperatures of the HPs, temperature and humidity of the surrounding air, volume of water drawn out of the storage tanks, as well as the electric energy consumptions of the systems. Performance measures evaluated included the coefficient of performance, the energy factor (EF), and the first hour rating (FHR). The HPWH systems gave EFs ranging from 1.8 to 2.5 and corresponding energy savings (and reductions in utility peak loads) ranging from 49.0% to 63.0%, approximately. The values obtained in the summer months were, as expected, somewhat higher than those obtained in the winter ones. The average values of the EFs and energy savings (and reductions in utility peak loads) were about 2.1 and 56.0%, respectively. FHR results were much lower for the HPWHs compared with those for the standard EWH. These results show that HPWHs are much more efficient compared with standard EWHs. While the average value of the EF for the EWH was about 0.92, the HPWHs yielded EFs averaging more than 2.00, resulting in annual energy savings averaging more than 50%. The results also show that HPWHs are effective at reducing utility peak loads, in addition to providing substantial cost savings to consumers.

Performance of Add-On Heat Pump Water Heater (HPWH) Systems and Their Impacts on Electric Utility Loads

2010 ◽  
Author(s):  
Yahya I. Sharaf-Eldeen ◽  
Craig V. Muccio ◽  
Eric Gay
Keyword(s):  
Heat Pump ◽  
Energy Savings ◽  
Electric Energy ◽  
Electric Heating ◽  
Electric Utility ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Energy Output ◽  
Water Heater ◽  
Heat Pump Water Heater

This work involves measurements, analyses, and evaluations of the performance of add-on, Heat Pump Water Heater (HPWH) systems in residential and small commercial applications. Two air-source Heat Pump (HP) systems rated at 7,000- and 12,000-BTU (2.051- and 3.517-kWh), were utilized in this work. The two HPs were retrofitted to two 50-gallon (189.3 liters) electric-resistance storage water-heaters with their electric heating elements removed. A third, standard electric water-heater (EWH), was used for comparison. The testing set-up was fully instrumented for measurements of pertinent parameters, including inlet and outlet water temperatures, inlet and outlet air temperatures of the HPs, temperature and humidity of the air in the surrounding space, volume of water draws out of the storage heater tanks, as well as electric energy consumptions of the systems. Several performance measures were used in this work, including the Coefficient of Performance (COP), which is a measure of the instantaneous energy output in comparison with the energy input; Energy Factor (EF), which is an average measure of the COP taken over extended periods of time; and the First Hour Rating (FHR), which is a measure of the maximum volume of hot water that a storage type water-heater can supply to a residence within an hour. The results obtained clearly indicate that, HPWH systems are much more efficient as compared to standard EWHs. While the average value of the EF for a standard EWH is close to 1.0, the HPWH systems yield EFs averaging more than 2.00, resulting in annual energy savings averaging more than 50%. The results also showed that, HPWH systems are effective at reducing utility peak demand-loads, in addition to providing substantial cost savings to consumers.

Simulation of indoor comfort level in a building cooled by a cooling tower–concrete core cooling system under hot–semiarid climatic conditions

2016 ◽  
Vol 26 (5) ◽  
pp. 680-693 ◽  
Author(s):  
D. G. Leo Samuel ◽  
S. M. Shiva Nagendra ◽  
M. P. Maiya
Keyword(s):  
Indoor Air ◽  
Cooling Tower ◽  
Cooling System ◽  
Fluid Dynamic ◽  
Climatic Conditions ◽  
Comfort Level ◽  
Passive Cooling ◽  
Computational Fluid Dynamic Analysis ◽  
Concrete Core ◽  
Core Cooling

Concrete core cooling system is an energy efficient alternative to the conventional mechanical cooling system. It provides better comfort due to direct absorption of radiation load, low indoor air velocity, apt vertical temperature gradient and absence of noise. It can be operated at relatively higher water temperature, which facilitates the use of passive cooling strategies. In this study, a cooling tower, which is an ‘evaporative cooling system’, is preferred over other passive cooling options due to its better cooling performance in dry regions and its ability to operate all through the day. This paper presents the results of computational fluid dynamic analysis of a room cooled by concrete core cooling system supported by a cooling tower. The study reveals that for a typical hot–semiarid summer climatic condition in India, the system reduces the average indoor air temperature to a comfortable range of 23.5 to 28℃ from an uncomfortable range of 35.3 to 41℃ in a building without cooling. The average predicted percentage of dissatisfied falls from 99.7% in a building without cooling, to 37.3% if roof and floor of a building are cooled with concrete core cooling system and further to 6.3% if all surfaces are cooled with concrete core cooling system.

Experimental Study on a Solar Powered Two-Stage Solid Wheel Desiccant Air Conditioning System

2012 ◽  
Vol 516-517 ◽  
pp. 1111-1116 ◽  
Author(s):  
Tong Hua Zou ◽  
Rong Yu ◽  
Lei Yan ◽  
Fa Li Cao
Keyword(s):  
System Performance ◽  
Electric Energy ◽  
Fundamental Principle ◽  
Coefficient Of Performance ◽  
Test Case ◽  
Two Stage ◽  
Electric Energy Consumption ◽  
Operation Conditions ◽  
Sorbent Materials ◽  
New Formulation

A new formulation, that employs both two-stage dehumidification and intercooler to effectively enhance system performance is proposed and investigated experimentally. The paper briefly describes desiccant wheel including the coupled fundamental principle and overall structure originally. An experimental setup is subsequently designed and built to evaluate the system performance under various operation conditions. The effects of different fresh air intake temperature at various regeneration temperature under given conditions are numerically analyzed and explained. Finally, results of a test-case are presented, indicating compared with the common single-stage system, an increase in humidity removal. Meanwhile, increasing regeneration air volume and temperature can significantly improve the dehumidification ability for sorbent materials and coefficient of performance of the system respectively, as well as save indirectly electric energy consumption, which is derived from the energy-intensive regeneration blower.

scholarly journals Electric energy consumption of milking process on some Finnish dairy farms

2017 ◽  
Vol 26 (3) ◽  
Author(s):  
Mari Rajaniemi ◽  
Tapani Jokiniemi ◽  
Laura Alakukku ◽  
Jukka Ahokas
Keyword(s):  
Energy Consumption ◽  
Energy Savings ◽  
Electric Energy ◽  
Cooling Water ◽  
Electricity Consumption ◽  
Dairy Farms ◽  
Energy Costs ◽  
Heating Systems ◽  
Electric Energy Consumption ◽  
Energy Saving Potential

The aim of this study was to examine the electric energy consumption of milking process on dairy farms and to evaluate the methods to improve the energy efficiency. The electricity consumption of the milking process was measured on three dairy farms in Southern Finland, and it varied between 37–62 Wh kg-1 milk.  The largest energy saving potential was identified in milk cooling and the heating of cleaning water. Even simple methods, such as placing the condenser of the refrigeration system outside, may reduce the energy consumption of milk cooling by 30%. Efficient milk pre-cooling can reduce the energy consumption of the whole milking process by more than 25%. Even larger energy savings are possible with a sophisticated milk cooling – water heating systems. It was concluded that there is a significant potential to reduce the energy consumption and energy costs of the milking process, and thus to improve the profitability and sustainability of the sector at the same time.

Sign in / Sign up

Export Citation Format

Share Document