It is impossible to transform the whole energy into useful work. It is impossible to increase the processes of cultivation of foods without water. It is impossible to separate all ions and minerals from water. Most of the real processes are thermodynamically irreversible. Calculations may indicate the fraction of efficiency of a thermal process. All the above mentioned facts have led to some proposals of cycles that exchange energy in order to produce a useful effect for the society. The key sustainable related parts are: to obtain water free of minerals or ions by distillation process. In this chapter, thermodynamic cycles will be explained for distillation using thermodynamic cycles of thermal machines called absorption heat pumps (AHPs). Distillation process offers to the AHPs an opportunity to diminish the consumptions of fossil fuels. The AHPs are able to work with 2% of mechanical energy to carry out a sustainable distillation process. Most of the energy of an absorption heat pump operation is thermal energy. The operation of the AHPs are defined with the coefficient of performance (COP); the variations of this parameter are shown as function of the different scenarios to obtain sustainable distilled water.
Part of the book: Distillation
In this chapter, the methodology to determinate heat load is revised and presented. The main parameters must be fixed as function of climatization, internal thermic conditions (comfort, temperature, and humid) and the activities. According with literature, the roof structural requirements were checked. These are an important parameter because it represents the limits to the system such as load by devices (weight of equipment), orientation in solar systems (operating conditions), and building materials. The method of calculation of solar available is shown; the aim is to achieve the major collection of solar energy. Finally, the plate heat exchangers can be fabricated in gasketed, welded or module welded design characterized by the model in which the flow channels for the two heat exchanging media are sealed. The kind of exchanger is suitable depending on your requirements. The thermodynamic method of calculation of sizing the exchangers is reviewed. The aim of this section is to find the suitable devices for the operation of air-conditioning absorption system based on hydroxide.
Part of the book: Sustainable Air Conditioning Systems
The energy consumption for space cooling is growing faster than for any other end use in buildings, more than tripling between 1990 and 2016. The efficient use of energy is important to reduce the consumption of electricity of conventional air conditioning. This chapter presents a thermal analysis of absorption and adsorption chillers for conditioning the airspace in a building, controlling the hot maximum temperature at the generator input with a modulating tempering valve (MTV) programmed in TRNSYS and Excel software. The energy performance of the system was maximized based on the tilt of the solar collector, storage tank specific volume, and input generator temperature. The results showed that 35 and 27 l/m2 of specific volume is a good choice for absorption and adsorption chiller without MTV, and 23 and 22 l/m2 were selected absorption and absorption chillers using the MTV at a fixed tilt angle of 7° of the solar collector and selecting a minimum temperature at the generator input of 111 and 109°C for absorption chiller without and with MTV, respectively, and 75°C for adsorption chiller without and with MTV. The use of MTV represented a significant reduction of the heater energy for both chillers, mainly for absorption chiller.
Part of the book: Zero and Net Zero Energy