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Beneficial Residential Building Uses of Electricity
Published in Clark W. Gellings, 2 Emissions with Electricity, 2020
Heat pump water heaters (HPWH) are significantly more energy efficient than electric resistance water heaters and can result in lower annual water heating bills for the consumer, as well as reductions in greenhouse gas emissions.
Role of Phase Change Materials in Solar Water Heating Applications
Published in Amritanshu Shukla, Atul Sharma, Pascal Henry Biwolé, Latent Heat-Based Thermal Energy Storage Systems, 2020
Shailendra Singh, Abhishek Anand, Amritanshu Shukla, Atul Sharma
Small SWHS is suitable for domestic purposes while larger systems are used in industrial processes. Majorly there are two types of water heating systems are available: (1) Natural circulation or passive solar system (thermosyphon): This type of solar water heaters is comparatively simple in design and also has low cost. In this type of system, the tank is located above the collector and water is circulated due to density difference when heat is added through collectors. However, their applications are usually limited to nonfreezing climates although they may also be designed with heat exchangers for mild freezing climates if required; (2) Forced circulation or active solar system: Forced circulation water heaters are used in freezing climates and for industrial process heating purposes. It contains a pump for circulation of water and it is operated through differential thermostat for maintaining the required level of water at the desired temperature difference of inlet and outlet water. Here a check valve is also needed to prevent reverse circulation.3
Modular Systems for Energy Conservation and Efficiency
Published in Yatish T. Shah, Modular Systems for Energy Usage Management, 2020
ZEBs are built with significant energy-saving features. The heating and cooling loads are lowered by using high-efficiency equipment (such as heat pumps rather than furnaces. Heat pumps are about four times as efficient as furnaces) added insulation (especially in the attic and in the basement of houses), high-efficiency windows (such as low-E triple-glazed windows), draft-proofing, high-efficiency appliances (particularly modern high-efficiency refrigerators), high-efficiency LED lighting, passive solar gain in winter and passive shading in the summer, natural ventilation, and other techniques. These features vary depending on climate zones in which the construction occurs. Water heating loads can be lowered by using water conservation fixtures, heat recovery units on wastewater, and by using solar water heating, and high-efficiency water heating equipment. In addition, daylighting with skylights or solar tubes can provide 100% of daytime illumination within the home. Nighttime illumination is typically done with fluorescent and LED lighting that use 1/3 or less power than incandescent lights, without adding unwanted heat. Miscellaneous electric loads can be lessened by choosing efficient appliances and minimizing phantom loads or standby power. Other techniques to reach net zero (dependent on climate) are Earth sheltered building principles, super insulation walls using straw-bale construction, Vitruvian built prefabricated building panels and roof elements plus exterior landscaping for seasonal shading.
Design and monitoring of a hybrid energy system: performance analysis and modelling
Published in Cogent Engineering, 2021
Stephen Tangwe, Mandlenkosi Sikhonza
Globally, sanitary water heating is among the services responsible for daunting energy consumption in the residential sector and is predominantly achieved by the use of inefficient geysers. The electrical energy consumed due to water heating can be reduced by the utilisation of solar water heaters or air source heat pump water heaters. The energy saving due to hot water heating can be further improved with the implementation of a hybrid energy system (combine solar water heater and an air source heat pump water heater).
Experimental analysis of convective heat transfer on tubes using twisted tape inserts, louvered strip inserts and surface treated tube
Published in International Journal of Ambient Energy, 2020
M. Abeens, M. Meikandan, Jaffar Sheriff, R. Murunganadhan
The electricity consumption of a water heater is quite huge and it is one of the daily necessities in our day-to-day life to heat up water. So replacing the existing method of water heating by conventional sources of energy with solar water heating will reduce the energy consumption by a considerable amount. The solar energy as a permanent solution to the existing problem will be the most apt one.
Study of the Thermal Behavior of Multi Tube Tank in Heat Recovery from Chimney—Analysis and Optimization
Published in Heat Transfer Engineering, 2018
Mahmoud Khaled, Mohamad Ramadan
Indeed heat recovery may be performed in several forms depending on the source of heat, the application where the extracted heat will be used and the tool recovering the waste heat. That is why in the last decade a large panel of waste heat recovery applications has been developed such as using thermo-electric generators [9–14] or enhancing Rakine cycle [15–17]. However if efficiency and flexibility are imposed as objective functions, one of the optimal use of waste heat is water heating [18–23]. The reason is that water heating requires a major share of energy consumption in buildings where living and food preparation occur. The energy consumed by water heating can be easily considered more than one third of an average household's energy consumption, consequently, in order to save energy, it is important to heat water efficiently. Indeed water heating from recovered heat can be applied to any engineering system evacuating recoverable heat, using heat exchanger [24–31]. A typical system for heat recovery is chimney. It is a thermal system that burns fuels or firewood to produce heat which can be transferred in part and not totally to the space to be conditioned. During the transformation cycle, considerable magnitudes of heat energy are lost through the exhaust gases which can reach temperatures as high as 300°C or more depending on the application. On the other hand, in countries with heavy dependency on imported fossil fuel, insufficient electric power production, and weakness in the energy management in most of its power domains, it is worth investigating the waste heat recovery for water heating. To this end, the present work suggests to use Multiple Tube Tank (MTT) heat exchanger to recover the waste heat of chimney exhaust gas. A prototype is implemented and tested and experimental analysis is performed. The main idea of this work is to enhance the heat recovery from chimney exhaust gas by using MTT heat recovery system. Moreover an optimization study is performed in order to find the optimal geometrical configuration of MTT system in terms of the number of tubes depending on the physical parameters of the system such as the exhaust gas temperature and the gas mass flow rate.