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A framework for creating thermal zones in a building for effective and efficient heating ventilation and air conditioning (HVAC) system design is introduced here. This method is based on simple “sort and eliminate” schemes and requires design cooling loads of conditioned spaces obtained from load calculation tools as primary input. The developed methodology is applied for creating thermal zones, determining corresponding supply conditions and ascertaining sizing of a dedicated outdoor air system (DOAS) with local recirculating units. A simulation study on a prototype-building model shows that a DOAS coupled with zoned recirculating systems that serve distinct thermal zones in a building (zoned model) perform comparatively better in controlling both space temperatures and humidity without significantly compromising HVAC energy and chiller loads than un-zoned HVAC systems serving the whole building as a single thermal block (un-zoned model). The consistency in the performance of zoned HVAC systems is verified by applying three different simulation weather files for New Delhi. Better performance along with logical and computational simplicity makes this design procedure a good alternative to traditional methodologies.

Although wrap-around heat pipes (WAHP) are widely used for enhanced dehumidification systems in tropical and hot-humid climates, very few literature resources have actually reported any control methodology applicable for WAHP dehumidifier systems for an entire year’s operation. In the present work, a methodology is proposed for an outdoor air unit equipped with a WAHP-based dehumidifier along with other auxiliary components. For this, the ambient conditions over an entire year are categorized into six constituent regions based on temperature and humidity levels. The proposed method involves defining specific control sequences corresponding to ambient conditions under each psychrometric region for tandem operation of system components. Fundamentally, this establishes a sort of segregated climatic control protocol for maintaining acceptable levels of humidity and temperature inside the conditioned spaces during a whole year’s operations. An energy simulation study is performed for two DOE prototype office buildings with six representative weather locations ranging from extremely hot and humid to dry and hot as per ASHRAE’s climate classification. Results show that a 100% outdoor unit comprising WAHP-based dehumidifier system equipped with proposed climatic controls saves cooling plant energy in a range of 1.5–19%, when compared with a similar WAHP-based outdoor unit without any climatic controls and auxiliary components. The proposed controls also enable the outdoor air unit in maintaining comparatively better indoor environmental conditions (temperature and relative humidity), resulting in lesser number of building occupied hours drifting away from prescribed indoor temperature and relative humidity limits than its basic counterpart without any climatic controls. This substantiates the intent and applicability of proposed control methodology for WAHP-based dehumidifier systems.

In this study, energy and exergy analysis was used to evaluate the performance of a vapor compression refrigeration system with a flooded evaporator and the causes of high temperatures of beverage during the production process determined. Subsequently, the components of the operation that require modification were identified in order to improve the system performance. The actual operating parameters related to energy and exergy analysis of the investigated beverage manufacturing plant were measured, the thermal properties of the beverage were determined from a calorimeter experiment, and mathematical models were developed based on the first and second laws of thermodynamics from the literature. The system energy and exergy efficiencies were 57.46% and 21.17%, respectively, whereas the system exergy destruction was 695.71kW. The highest exergy destruction among the components of the refrigeration system occurred at the cooling plate, followed by the ammonia compressor. The cooling plate also experienced a loss in the refrigerating effect of 43.59kW. Therefore, the cooling plate is the area with the highest potential for improvement. The ammonia compressor presents another potential area of improvement, which includes operating the compressor at a high compression ratio and high superheated temperature. However, the reduction of beverage inlet mass flow rate at the cooling plate offers the best opportunity to achieve a low beverage temperature between 1.00^∘C and 2.00^∘C and decreasing the system exergy destruction without incurring additional investment costs.

This paper presents the analysis of a modified vapor compression cooling system which uses an ejector as an expansion device. Expanding refrigerant in an ejector enhances the refrigeration effect and reduces compressor work. Therefore, it yields a better coefficient of performance. Thermodynamic analysis of a constant area ejector model has been done to obtain primary dimensions of the ejector for given condenser and evaporator temperature and cooling capacity. The proposed model has been used to design the ejector for three refrigerants; R134a, R152a and R1234yf. The refrigerant flow rate and the diameters at various sections of the ejector have been obtained by doing numerical modeling in Engineering Equation Solver (EES). Refrigerant R1234yf demanded the highest diameter requirements at a fixed 5^∘C evaporator temperature and 40^∘C condenser temperature for a given range of cooling load. Both primary and secondary refrigerants flow rates are higher for R1234yf followed by R134a and then R152a.

This chapter carries out an investigation on the consumption of energy and emission of CO₂ in 16 Students’ halls of residence (hostels) in Lagos, Nigeria, to gain an understanding on the status, impacts and performance of energy use in public student residences. The use of energy in Nigeria was highlighted and the continuously evolving built environment was shown to have an impact on the electricity infrastructure of the nation. Residential buildings were shown to significantly impact energy supply around the world. Methods of benchmarking were applied for the identification of variables capable of impacting on the consumption of energy in the buildings, these methods also identified the variables that significantly correlated with the energy consumption. The energy usage intensity (EUI) was characterized and with EUI acting as an indicator for building energy performance (BEP), the derived annual benchmark range of EUI was derived and given as 93.61–147.1kWh/m². The CO₂ emission levels were calculated using an emission factor and correlation analysis was carried out to show that floor area, number of occupants and number of rooms all had significant correlation with the CO₂ emissions.

Arguably, to nourish or take care of the needs of all of humankind — sustainable and affordable access to clean water, safe sanitation, and clean air, together with a sufficiency of energy, food, and shelter — should be universally available. Yet, many humans do not enjoy such access or availability, even though it has been 70 years since the 1948 United Nations (UN) declaration on human rights proclaimed “that all human beings are equal, and have inherent rights.” However, only food and shelter were explicitly mentioned in the initial declaration. Others were recently added to the UN list, but not air and energy. Nevertheless, basic human needs do not have to be declared as a human right before national actions are taken. Today’s key driver is the UN 2030 Agenda, a plan to eradicate all global poverty and set the world onto a “sustainable and resilient path,” through the achievement of 17 Sustainable Development Goals (SDGs). Adopted by all UN members, the 2030 Agenda in essence, is a 21^st century version of the 1948 proclamation. The SDGs explicitly detail, or implicitly in the case of clean air, all the necessary needs for the nourishing of tomorrow. To achieve the plan will likely require, at least, changes in national cultural values, eliminating inequalities and disparities, developing more appropriate governance strategies, and meaningful technical innovation. In this chapter, these requirements are discussed against a backdrop of presently known deficiencies in global nourishment needs.

This paper investigates the feasibility of recycling waste heat from a diesel engine, and also the effects of using ethanol-diesel oil as an alternative fuel. Through thermodynamic analyses, the study reveals that a significant amount of energy is contained in both the exhaust gas and cooling water, and that recycling this energy will reduce emissions, conserve energy, and improve the thermal and exergy efficiency of the diesel engine. The use of ethanol-diesel oil will lead to significantly reduced exhaust emissions without significant impact on the engine's performance parameters.

As a kind of development theory, sustainable development is becoming the world's common development philosophy and principles; energy is an important part of sustainable development. At present, China's energy legislation has been enacted many laws and regulations, but has not yet constitute a sound legal system, supervision mechanism is not reasonable, legal lack of maneuverability. We must be guided by the sustainable development, improve the energy law system, rationalize the management mechanism, enhance the maneuverability of the energy law, energy to accelerate and perfect the legislation, promote the harmony of man and nature.