Assignment Cover Sheet Faculty of Science, Engineering and Built Environment STUDENT ID:217096262 ____________________________________________________ UNIT CODE: SEN700 RESEARCH METHODOLOGY _____________________ ASSIGNMENT No.: 1__________________________________________________ ASSIGNMENT NAME: LITERATURE REVIEW DUE DATE: 03rd April_______________________________________________________ Plagiarism and collusion Plagiarism occurs when a student passes off as the student’s own work, or copies without acknowledgment as to its authorship, the work of any other person. Collusion occurs when a student obtains the agreement of another person for a fraudulent purpose with the intent of obtaining an advantage in submitting an assignment or other work Declaration I certify that the attached work is entirely my own (or where submitted to meet the requirements of an approved group assignment is the work of the group), except where work quoted or paraphrased is acknowledged in the text. I also certify that it has not been submitted for assessment in any other unit or course. I agree that Deakin University may make and retain copies of this work for the purposes of marking and review, and may submit this work to an external plagiarism-detection service who may retain a copy for future plagiarism detection but will not release it or use it for any other purpose. DATE: 03rd April___________________________________________________________ An assignment will not be accepted for assessment if the declaration appearing above has not been duly completed by the author. Design and development of low energy consuming Heating, Ventilation and Air Conditioning (HVAC) systems Keywords: HVAC, Low energy, vapour compression, vapour absorption, thermal storage, condensers Introduction: Heating, Ventilation and Air Conditioning system is mainly used to regulate the temperatures and quality of air inside the buildings for increasing the comfort of occupants. HVAC is the major energy consumption source in many commercial buildings in Australia. According to the fact sheet of National Energy Efficiency Network, 40 % of the energy consumption in all commercial buildings in Australia mainly due to the HVAC system. The use of HVAC came into existence after World War 2 due to boom in manufacturing industry. Following this, the energy prices soared in 1970 which made the engineers started to design an HVAC system which consumes less power without effecting the performance of the system. The main aim of this literature review is to identify the current trends and future improvements to be made for designing and developing an energy efficient HVAC system. Literature review: HVAC system design contain many components where each of them have their own performance factors and design considerations for effective operation. Energy consumption by HVAC system can be reduced in two basic ways called quick wins by controlling the operation of HVAC according to the requirements of comfort and strategic concepts includes the technical design and increase the performance of all HVAC components [1]. Quick wins: The design of buildings must be integrated with HVAC system design which results in high performance buildings. Some of the major benefits of this low energy building designs are providing higher insulation, occupancy sensors, photo sensors, limiting of window areas [2]. [3] identified that the performance of HVAC can be done by quick wins by constructing a low energy buildings with insulation, white roof, air tight buildings, low heat generating equipment’s, smart sensor and automation, light efficiency and quality control. In addition to this, use of renewable energy also helps in reducing energy consumption. In addition to these, building orientation, structural materials, insulation and sealing, renewables, etc. [3]. Fig 1: Quick wins for increasing the performance of HVAC and reducing energy consumption [4] Strategic methods: Strategic concepts play a crucial role in efficient operation of HVAC systems in which the technical design, configuration and components used in HVAC system are considered [5]. According to [5], the major strategies to design an energy efficient HVAC system is shown in figure-2. [6] stated that decoupling of ventilation and cooling systems increases the performance of the systems dates to century in which the energy consumed by the fan is reduced. In addition to this, Variable Air Volume system is the most emerging technique which removes the hot air vents which in turn increases the performance of HVAC system. [2] identified that the energy consumed by the fan is reduced by reducing the internal static pressure of the of system. [7] states that a direct evaporative cooling system in which water is used as refrigerant which decreases the emission of carbon gases into the environment and minimum consumption of energy and provide high ventilation and cooling effect. [8] proved that the performance of cooling effect can be increased when the vertical heat exchanger cools the air entering in indirect evaporative cooling system. [9] investigated that performance of evaporative cooling system can be maximised when air sensible heat exchanger is integrated with cooling coil unit in which firstly the air sensible heat exchanger is used to reduce the dry bulb temperature of the air entering the cooling unit due to energy exchange between outside building air stream. On calculating the performance of this hybrid evaporative cooling system with the ordinary system, results show that 52% of the energy savings are attained than normal usage [5] [9]. Fig-2: Current Energy efficient strategies in HVAC Systems design and development Generally, vapour compression refrigeration system requires high amount of energy than normal refrigeration systems. Addition of air cooled condensers helps in decreasing the temperature of air as it emits more heat and reduces the usage of compressor. [10] stated that thermal storage systems can also increase the effectiveness of HVAC systems as it helps in producing the cooling effect during peak hours. [11] identified that heat recovery technique helps in reducing the consumption of energy by transferring the heat between outlet air and inlet air. [12] found in experimental analysis that heat flow rate increases with air flow rate. [13] identified that by using direct digital controllers in variable air volume system, the energy consumed by compressor can be increased. [14] and [15] used the concept of energy management system in HVAC systems to reduce the consumption of energy. Hypothesis: The main aim of this task is to design and develop an HVAC system which consumes less amount of energy and low maintenance cost. Based on the literature review, a high amount of research is done considering either refrigeration cycle or concentrating on component of the system. There is a gap between quick wins and strategic techniques combination to increase the performance and build an efficient HVAC system. Conclusion: An effective HVAC system which consumes less amount of energy without effecting the performance of the system decreases the 40% of energy bills. In addition to this, systems which emit less amount of carbon helps in providing effective working environment. Bibliography [1] D. o. I. Australian Governement, "NEEN fact sheet on Energy efficiency of HVAC systems," National Energy Efficiency Network, April 2015. [2] A. L. Kurt Herzog, "Achieving High Satisfaction in High Performance Buildings," ACEEE Summer Study on Energy Efficiency in Buildings, pp. 1-3, 2016. [3] "Energy efficient farm buildings," FARM ENERGY INNOVATION PROGRAM ENERGY IN SHEDS, NSW, 2015. [4] S. C. M. Hui, "HVAC Design and Operation for Green Buildings," Refrigeration and HVAC, pp. 44-51, 2001. [5] ⇑. B. S. b. A. F. c. K. P. d. Vahid Vakiloroaya a, "A review of different strategies for HVAC energy saving," Energy Conversion and Management, pp. 738-754, 2014. [6] P. L. A. Robert L. Tazelaar, "CURRENT TRENDS IN LOW-ENERGY HVAC DESIGN," Perkins will research journal, pp. 55-62, 2013. [7] Y. Jiang, "Theoretical and testing performance of an innovative indirect evaporative chiller," Solar energy, December 2010. [8] t. V. Khalajzadeh, "A novel integrated system of ground heat exchanger and indirect evaporative cooler," Energy and buildings, pp. 604-610, June 2012. [9] V. Vakiloroaya, "New integrated hybrid evaporative cooling system for HVAC energy efficiency improvement," SI international, pp. 772-776, 2011. [10] t. A.-a. Abduljali, "Review of thermal energy storage for air conditioning systems," Renewable and Sustainable Energy , pp. 5802-5819, October 2012. [11] B. J. Brinkworth, "Refrigeration and Air Conditioning," Journal of Solar Energy Engineering, 1977 . [12] L. Zhang, "Energy requirements for conditioning fresh air and the long-term savings with a membrane-based energy recovery ventilator in Hong Kong," Energy , pp. 119-135, Feb 2001. [13] W. Chen, "Research on a novel DDC-based capacity controller for the direct-expansion variable-air-volume A/C system," Energy conversion and management, pp. 1-18, Jan 2010. [14] F. W. Yu, "Improved energy performance of air cooled centrifugal chillers with variable chilled water flow," Energy converison and management, pp. 1595-1611, June 2008. [15] G. E. D. Plessis, "A versatile energy management system for large integrated cooling systems," Energy conversion and management, pp. 312-325, Feb 2013.