Energy Efficient HVAC Systems: Study Proposal Essay.

Research project proposal (final report) that summarises the: research aims, scope and outcomes, literature synthesis, refined research question/s, research methodology, evaluation of safety, risk and ethical considerations, timeline of scheduled tasks, justification for necessary resources, need for research and research impact, team charter including team communication strategies, teamwork expectations and responsibilities.

Overview of HVAC Systems and Energy Consumption

Heating, Ventilation, and Air-conditioning (HVAC) systems are commonly used in diverse climatic regions worldwide. HVAC systems are comprised of components for supplying, filtering, cooling, heating and distributing conditioned air in buildings. Usually, there are two categories of HVAC systems that are high and low-pressure systems. These two systems function differently; high-pressure systems allow air to pass in their duct systems at high speed of about 10 to 25 m/s. High-pressure systems have small ducts, and also their duct system occupies less space, however, in this system the fans consume a lot of energy to drive the air. The velocity of the air in this system is reduced at the terminal which helps to prevent draught which makes the occupants uncomfortable. On the other hand, low-pressure systems have larger ducts thus low air velocity.

To avoid HVAC system are essential in maintaining favorable indoor air quality and provide thermal comfort in buildings. However, HVAC systems rate of energy consumption is very high. According to Perez-Lombard et al. (2008) in 2004, of all the energy consumed in the European Union and the USA, the building sector had consumed 37-49% of the energy. In the building sector in both the European Union and the USA, the HVAC systems accounted for the highest energy consumption rates of 48% and 57% respectively. In Australia HVAC systems usually account for about 50% of the energy used in industries. The fans alone accounted for 15-50 % of the energy used which is mostly determined by the type, model, and efficiency.

This indicates that there is a need for designing more energy efficient HVAC systems that will help improve the traditional systems with a better system that will help meet sustainable energy requirements in the future. There have been efforts made to reduce energy consumption in buildings by which mainly has been focusing on improving thermal properties of the buildings. These efforts have resulted in a significant reduction of energy consumption specifically the energy used for heating buildings. Power required in building services is expensive considering investments and CO2-emission, and thus there is need to develop energy efficient building services.

Building services are essential as they determine the ability of people to perform according to their performance. One of the most element of building services is ventilation. Like in other fields technology there has been technological advancements in ventilation. To achieve sustainable development efficient consumption of energy must be considered it is therefore important to consider energy use in all our systems. There are measures that can be taken to increase the efficiency of the HVAC systems and reduce energy consumption. This study focuses on designing mechanical HVAC systems that will reduce energy consumption and increase efficiency as well as the measures that can be taken to reduce energy consumption by these systems.

In the recent times, the increasing CO₂ emissions have led to significant climatic changes around the globe which have resulted in higher risks to human beings and the environment. As a result of the drastic changes in climatic conditions, there have been campaigns aimed at reducing the level energy consumption. The building sector is one of the sectors that consume a lot of energy can significant help in reducing the level of energy consumption if correct measures are taken to reduce energy consumption in this sector. As noted before in the European Union and the USA the building sector accounts for the highest percentage of energy consumption.

The Need for Energy Efficient HVAC Systems

The European Union initiated initiatives that would help in promoting energy performance of buildings. One of this initiative was the launching of the Energy Performance of Buildings Directive (EPDB) and published a recast in 2010 (EPDB. 2010). EPDB came up with a framework that guided energy performance of buildings which focused on space heating, domestic hot water, cooling, and lighting. EPDB directives are revised after every five years.

There is a need to improve indoor conditions by ensuring building are regularly renovated. According to Delsante et al. (2002), unfavorable indoor environment causes discomfort to the occupants which are usually attributed to by poor air quality. According to Wargocki et al. (2007), the performance and health of workers are affected by the poor indoor environment, and it also has an impact on the performance of pupils in the school. This makes businesses incur high cost in their operations.

Sustainable development cannot be achieved without the efficient use of energy. In the recent time, the efficient usage of energy has been optimized, and it has been a good strategy in reducing the costs incurred by businesses. One of the best ways to ensure that energy is consumed efficiently is by installing efficient systems that perform better while consuming less energy. In many countries, HVAC systems have been subjected to misuse by many businesses and industries. This has been attributed to overuse of the systems as well as the use of inefficient systems that require high energy to run. In many companies, HVAC systems have been accounting for the highest energy consumption rates which increase energy costs. Increased misuse of these systems in the companies has significantly affected their energy saving initiatives and objectives to reduce their operation costs.  The project aims at providing solutions that will help in the reduction of energy wastage.

The purpose of this study, therefore, is to provide an improved design of more efficient HVAC system and also suggest positive measures that will help in reducing energy consumption.

The current energy consumption by HVAC systems is alarming considering the need to have more energy effective systems so as to attain sustainable development through efficient energy consumption. The study focuses on the improvements that can be made on these systems as well as measures that need to be taken to ensure that these systems are functioning efficiently while consuming less energy. By considering HVAC systems in the energy management plans in buildings will help in ensuring that the occupants of the buildings are safe and they can perform at the highest level of their abilities. This will also help in reducing the cost incurred by businesses in terms of the energy consumed.

In buildings, HVAC systems are used in regulating temperatures, humidity and air conditions as desired by the occupants of the buildings. HVAC systems achieve this by transferring heat and moisture into and out of the air and also by filtering the pollutants in the air (Carbon Trust, 2017). According to Intergovernmental Panel on Climate Change (2007), the function of heating systems is to increase space temperature in order to compensate for the heat lost between the internal and outside space while the function of the ventilation systems is to extract air pollutants for the air. Cooling systems helps in lowering down temperatures this mainly occurs when temperatures rise for the people and saturate the building or when the weather is sunny, and there are high temperatures causing discomfort to the people.

Indoor Conditions and Energy Consumption

There are different HVAC systems depending on their functions and size. Some are largely designed to provide ventilation, heating, and cooling in buildings. There are also other systems that use boilers to heat buildings and radiators whose functions is to provide ventilation for providing fresh air or cooling some sections of the building. While these systems function separately it is important to consider energy consumption; it would be uneconomical to run two systems simultaneously for instance, by running the heating system while the cooling system is still running will lead to high levels of energy loss. To save energy, it is noble to ensure that two systems whose functions are not complementary are not running simultaneously.

Traditional boilers used coal, diesel of natural gas to produce hot water or steam. Other boilers use steel water tubes and have a combustion efficiency of 78 to 86%. The modern boilers are more efficient with a combustion efficiency of 96%. Compared to other boilers using other sources of energy boilers using natural gas have a higher combustion efficiency, and also their level of environmental pollution is very low. According to Sachs et al. (2009) heat pumped have been developed to replace the fossil fuel based boilers. Heat pumps extract underground heat and or from warmer sub-surface water during the cold seasons and to warm buildings. In warmer seasons the heat pump extracts high temperature from the buildings and pumps it outside the building to lower the temperature in the building (Aikins, K. and Choi, J. 2012).

The cooling systems use chillers to which produce cold water. The air handling units in which cold water is pumped to so as to cool the air. There are two categories of chillers that are, Mechanical compression chillers and absorption chillers. Centrifugal chillers are highly efficient and are the most suitable for large operations such as offices or large buildings. These chillers are categorized under mechanical compression chillers. Absorption chillers make use of heat source to cool water which can be gas burners or high-temperature water. They use hot water from thermal solar instead of using electricity. Thus they are environmentally friendly (Asdrubali et al. 2009).

There are three types of ventilation systems that are Variable Air Volume (VAV), Displacement ventilation, and Constant Air Volume (CAV). According to Terkildsen & Svendsen (2013) VAV have different air intake while maintaining constant temperatures in a building while the rate of air intake is constant while the temperature of the air supplied keeps on changing. VAV are better since they allow better control of temperature in a room, when used with fans with varying speeds VAV can save about 15% on energy use (Taylor, 2007).

Displacement ventilation is based on the ideology that ‘warm air rises.' Displacement, ventilations system functions by supplying conditioned air form as raised four systems. This system stratifies air in a room where the cool temperature is in the zone where people stay while it makes warm air to rise toward the ceiling of the building (Graham, 2009). Thus system aid in reducing the energy use by higher speed fans to drive cooler air downwards.

Purpose of the Study

It is essential to use highly efficient HVAC systems they have a potential of saving up from 30 to 40% of energy consumption. They show that they can be a significant economic and environmental development.  This also lowers GHG emissions, which comes from the building sector.  This in return also greatly benefits the building owners and the as well as the tenants since it lowers the electricity bills. Efficient HVAC systems also have a high chance of providing high-quality air conditions in the building.

• Design and layout of the building as well as the operations that take place inside the building. This influences the internal environment and conditions of the building.
• The desired internal conditions by the occupants, for instance, temperature, humidity, and air quality.
• The internal temperatures of the building which may as a result of lighting systems or the people occupying the building.
• The design and the efficiency of the HVAC system also determine how it controls the environment inside a building.
• The time at which the HVAC system is operating.

According to International Energy Agency (IEA) (2011), the current trends of energy consumption are unsustainable economically, socially and environmentally. If interventions will not be made global energy-related greenhouse gas (GHG) emissions will increase by more than 50% by 2050 and there will be a higher demand for oil due to increased concerns about the security of supply. It is also estimated that the growth of households will increase by 67% while the commercial building will increase by 195%. So as to attain sustainable development, it will be essential to adapt safer energy use practices all over the world. If the building sector embraces low or zeroes carbon energy technologies to run their HVAC systems, this will be a big step forwards towards achieving sustainable development. There is a need to adopt clean energy or renewable energy to reduce GHG emissions, and every country should take part in this so that we can achieve a universal goal.

Building account for a third of the energy consumed globally and therefore, they can also be considered a significant source of CO₂ emissions. HVAC systems are estimated to consume more than 50% of the energy consumed by buildings globally. Therefore, there is need to consider HVAC systems that will deliver efficiently while consuming less energy this will help in reducing CO₂ emissions globally. The world should now focus on Energy- Efficient Building for HVAC systems. This study will present the Thermal Energy Storage Systems which can be used to effectively and efficiently run HVAC systems in buildings and will help in reducing CO₂ emissions.

According to Zhang et al. (2015) can be sued in various areas such as industries or solar plants where it is used to transfer heat energy to storage media in the charging process and the energy stored can be used later during the discharging process. Thermal energy storage functions as a battery for the air conditioning systems of a building. Thermal energy storage is designed to collect excess energy and save it for use in the future by individual buildings, towns, districts and other regional scales. This system balances energy demand between daytime and nighttime or seasonally. For instance, the solar energy collectors in the system can collect and stored heat energy during the summer for use during winter which is cold. On the other hand, it can store cold during winter which can be used for cooling buildings during summer.  In other words, thermal energy storage can be charged with heat or cold which can be utilized in future. One of the most common thermal storage systems is the insulated hot sanitary water tanks. These storage systems are cost effective and can be used to stored energy for days or even weeks.

Scope and Outcomes of the Study

It is important to use thermal energy storage because of the following reasons;

• Thermal energy storage helps avoid partial load operation of the system=m thus increasing its efficiency. This is because it can correct waste energy which can be used for days, weeks or even months.
• They reduce on the investments in energy and infrastructure as well as reduce cost.
• They help in making sure renewable energy is used sufficiently by storing so that it can be used later when it will be on demand.

According to Roth (2007) in any countries storage of chilled water and ice in large is being embraced since it helps reduces costs for customers by reducing peak loads. By integrating ice storage, thermal storage helps in reduction of chiller capacity by 50% which consequently lowers electrical peak demand in the production of chilled water. Thermal energy storage is also being used to in storing solar energy which is used for heating households’ water heating and cooling at a lower cost.

Other than the solar Thermal energy storage can also get energy from heat pumps for off -peak, lower coat electric power, heat from combined heat and power (CHP) power plants, renewable electrical energy and heat energy lost in industrial processes. The system mostly depend on renewable sources of energy which mean that it is environmentally friendly (Hviid  & Svendsen, 2010)

1. Sensible heat storage- this type depends on a medium that is heated or cooled, for instance, heated of chilled water in the tank. This type has a low energy density. In most cases it consists of insulated tanks or the tanks are stored underground in the ground as the insulator. It may also include water stored in boreholes (ESTTP (European Solar Thermal Technology Platform) 2007).
2. Latent heat storage- depends on the change of water phases that is from water to ice in the process of storing and releasing energy with any change in temperature.
3. Thermal-chemical storage- this type of thermal energy storage utilizes the energy that is released from reversible chemical reactions to store energy.

Use of solar thermal in the building would be more effective since solar thermal technologies are readily available in the market. If utilized properly solar thermal will be able to provide space and water heating need for many households in the future. They can be used in small scale and in large scales that is for single to multi-family as well as in industries and commercial buildings (BCA 2007)

1. Integration of solar collectors in building components- this is by setting solar collector on building envelopes this will make building to become multifunctional.
2. Alternative materials such as polymers or plastics can be used in solar collectors which are designed to resist stagnation of temperatures and new materials that will be able to resist Ultra Violet exposure this could greatly lower the cost of solar thermal systems.
3. Solar cooling systems- these systems require compact thermally driven cooling cycles that are sorption chillers and desiccant systems.
4. Intelligent control systems this can be enhanced through effective communication with the energy management systems to make significant use of the solar energy available.

• It is essential to carry pout maintenance of HVAC systems regularly. This helps in ensuring that HVACS are operating at efficiently. Maintain ace does not only increase the efficiency of the machine but also increases the lifespan of the equipment. Maintenance should be a regular and a continuous activity and should be carried out by qualified technicians. Maintenance practices of  HVAC systems should include, cleaning the heat surfaces, repairing and replacing worn outputs such as the ductwork insulation, air filters, leaking dampers on ventilation systems, refrigerant pipework, etc.
• HVAC systems should be monitored continuously to check on their functioning.
• Ensure that there is proper utilization of electricity. It is necessary to identify why the HVAC systems are running and control how they are being operated to save electrical energy. This can be achieved by using air conditioners that use less energy and can maintain a lower temperature that the outside temperature. Also, this can be achieved through reducing the cooling load that is. The amount of heat that the systems have to generate. It is also important to ensure that there are no systems running simultaneously without complementing each other. For instance, you should not allow heating and cooling to run at the same time.
• Building and companies should adopt energy saving practices. It is important to ensure that good housekeeping which can be done through educating other people who are responsible for HVAC on how effective use of the system will contribute to the reduction of energy costs(Smith, 2008).
• Embracing new and efficient technologies. It is advisable to replace the old and inefficient HVAC systems with advanced ones which are more efficient and consume less energy. It is efficient to use HVAC systems that are more energy efficient and not just replacing them with similar systems.

1. What measures can be taken to reduce energy wastage through HVAC systems?
2. How can we use renewable energy to run HVAC systems?
3. Will the improvement of HVAC system have a significant impact on attainment of sustainable development:

1. To identify the measure that should be taken to reduce energy wastage through HVAC systems.
2. To determine how renewable energy can be used to run HVAC systems.
3. To examine whether improvement of HVAC will have a significant on the attainment of sustainable development.

Research methodology is the procedural, theoretical analysis of methods used in conducting research. Research methodology enables the researcher to analyze research methods theoretically and identify principle related to a given field of study. Howel (2013) defines research methodology acts as the guide in the whole process of the research. Research methodology is essential in helping researchers identify the method of research used in a study. Herman, (2009) noted that research method could be differentiated from research methodology by the fact research methodology does not provide solutions to the study but provides a better understanding of the methods which helps the researcher determine the most appropriate method for the study and to identify the how he can carry out the research more effectively. On the other, research methods refer to the modes and means of collecting data.  According to Bruce (2009) does not describe a specific research method but it provides a guide on how research will be carried out.

In this research study, the researcher used literature review as the research methodology. Literature research methodology entails reading, analyzing, and sorting literature with an aim to identify the required materials. This methodology does not involve the direct study of the object under study. The researcher instead used other literature material which has been studied previously to access information about the research topic (Lin, 2009).  Comerasamy (2015) describes literature based methodology as the designing research projects while using the existing literature as the study population where the researcher gets his or her sample and collects, analyzes data while considering ethics in research. This research methodology comprises of two methods of data collection which are a systematic literature review or systematic overview and Traditional literature review or narrative or comprehensive research methods.  The researcher used systematic literature review which is defined as a scientific method which is used to communicate and summarize the results and the implications of research studies which could be hard to understand and comprehend.

Functioning of HVAC Systems in Buildings

This type of literature is important in helping researcher gain a better understanding of the research topic based on what other researchers had studied in the past. The researcher is also able to compare views from different researchers and thus develop a greater understanding of the information.  In this study, the researcher borrowed information from various scholars who have previously researched on the topic.  

Ethical considerations are essential in any research the researcher should be aware of the ethics that he or she is supposed to observe when carrying out research. While using literature review methodology, the researcher should consider the following ethical issues.

The researcher should not copy any published work and present as his own. In this research ensured that the work presented was the original work which has not been published previously. It is essential to identify that primary data should only be published once by the original author. Whenever the researcher borrows some ideas from another author, then it should be cited appropriately. The researcher in this study ensured that all information borrowed from other authors was cited correctly.

Plagiarism results from using another person’s words, images, data, and ideas, with acknowledging them or without prior permission from the owners. It is considered an act of dishonesty when one takes another person’s work and publishes it as his own and therefore, as a researcher one should avoid plagiarism at all cost. It acceptable to use another person’s work but it should be quoted, and the author acknowledged. By citing the authors, one is able to identify the original owners if an idea, however, it is unethical to use their words in framing the idea the researcher is required to paraphrase the information without losing the original meaning of the author. It is unacceptable present another person’s ideas as our own. The researcher ensured that he did not plagiarize works from another author (Wager & Wiffen, 2011)

According to Wager & Wiffen  (2011) It essential to acknowledge those people who were involved in the research as well as the intentions for carrying out the research as well as the source of funding if any. As a view author, it is necessary to indicate the competing interests of carrying out the research clearly. This is to show that the researcher was not biased in giving his views. The research should also be presented to the relevant authorizes and every party who have a legal right to access the information gathered.

The researcher should ensure that the data corrected in the research is accurate. The researcher should not also try to divert any information given but instead should present it as collected. The researcher should be responsible and should consider extracting accurate data. This was achieved through proofreading of the written research by another author to identify any gaps that could arise from the research (Wager & Wiffen, 2011).

The purpose of the study was researched designing and developing a low energy consuming heating, ventilation and Air conditioning (HVAC) systems. The research also aimed at identifying ways in which energy consumption by HVAC systems can be reduced by using more efficient systems and also use of renewable energy to run HVAC systems and also to reduce CO₂ emissions into the environment. This will greatly help in reducing global warming which has resulted in major climatic conditions which have been endangering the environment as well as the people. Global warming has resulted in climatic disasters such as floods, droughts, and landslides among other calamities (Akbari et al. 2008)

The study is based on literature review. Therefore, every member of the group shall carry out research on the relevant literature depending on the task that he shall be given. Then the group shall be converging and discussing the finding from each member.

This study will be carried out by a group of five researchers for a period of one month. Each researcher will be presented with a task. The group shall be meeting thrice in a week that is on Mondays Wednesdays and Thursdays for the whole period that the research will be carried. During these meetings, the group shall be discussing findings from each member and also identify the challenges that each could be facing so that they can be solved in the group. The group shall also set goals which they want to have achieved after every week. The goals shall be evaluated using the progress and the achievements made so as to know if they have been attained or not.

Communication is an important factor in the efficient working of a team. The research group has come with a communication strategy that will enable all the members to get the required information. Proper communication in the team allows members of the team to work together and also enhance their potential of performing at the highest level. The following are the strategies laid by the group to ensure that they shall be communicating effectively throughout the research period.

According to Moira (2016), the team has to agree to on a regular basis through the research period to strategize and discuss any issues that may be facing during research. Meetings also help everyone in the group to participate and present his or her finding to other group members for discussion and create a fair opportunity for everyone to voice their voices and share concerns with other group members. The team also strategized on how they could ensure that their meeting are held on time and as scheduled by,

• Assigning one member the responsibility to become the timekeeper.
• Prepared an agenda that will be given to every member of the group before converging for the meeting. Therefore, everyone comes will attend the meeting ready for the planned proceedings.
• Before the meeting, the group sectary asks all groups members to be prepared for the discussion of the agenda items.
• The group does not allow any discussion of non-scheduled agendas, and if important they should be discussed after discussing the scheduled agendas.
• The meeting is planned in advance to allow members to prepare on time.

Any information concerning the group must be communicated to every member of the group without discrimination. To ensure this, the group secretary sends emails and a message to every member of the group about anything that is related to the group activity (Moira, 2016)

By being transparent, clear and concise helps in our communication helps safely a lot of time as well as ensuring efficiency in the operation of the group.

Every member of the group is required to conduct himself or herself with the utmost respect by observing the values of the group. Regardless of the position that one holds in the group, it is essential to respect everyone so as to ensure that every member of the groups feel appreciated and thus they cannot fail to comply with others during the research program. It is also essential to listen and consider the very person point of view. (Moira, A. 2016). In case the member has made a mistake it is sensible to correct him or her I the most appropriate manner.

Every member of the group is fully aware that they should accept any mistake they do or even if their give wrong opinions they should accept their mistakes and be open to being corrected. This allows the group in the discussion and in meeting to come up with agreement easily instead of wasting a lot of time arguing while trying to defend his or her mistake. 

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