**2. Thermal capacity of the building**

#### **2.1. Determination of the working operation time of the absorption cooling system**

An analysis of the environmental temperature was carried out in order to select the operation time of cooling absorption system. The TRNSYS software was used to simulate the building because it has implemented meteorological data such as radiation, environmental temperature, wind velocity, and so on for different cities around the world. **Figure 1** shows environmental temperature and global radiation profiles along a year (0–8760 h) at Temixco city, Mexico. The selected period was from March to May (1460-3560 h) to operate absorption system due to the high environmental temperature (**Figure 2**).

#### **2.2. Determination of the cooling capacity of the building**

The TRNSYS software has the advantage to simulate different kinds of processes (called types) such as pumps, photovoltaic modules, solar collectors, controllers, buildings, among others, and they can interact with each other with the environment in a dynamic way along time. The heat generation of the building considers four people in a rest position and three computers turned on from 8:00 to 18:00. Dimensions and main building characteristics are shown in **Table 1**.

Design and Construction for Hydroxides Based Air Conditioning System with Solar Collectors… http://dx.doi.org/10.5772/intechopen.72188 45

**Figure 1.** Environmental temperature data for an estimated year time in the TRNSYS software.

**Figure 2.** Photograph of the thermal and photovoltaic solar systems on the building roof.


**Table 1.** Home characteristics.

**1. Introduction**

44 Sustainable Air Conditioning Systems

with LiBr/H2

single-effect LiBr/H<sup>2</sup>

range of driving thermal source, single-effect LiBr/H<sup>2</sup>

**2. Thermal capacity of the building**

system due to the high environmental temperature (**Figure 2**).

**2.2. Determination of the cooling capacity of the building**

The world's main development is the energy because the technological advances and economic growth in countries rely on it. The energy demand is basically affected by three major factors, namely, population, economy, and the per capita energy consumption. The increase in energy demand leads to increased greenhouse gas emissions associated with the burning of fossil fuels and contributes to global warming. The energy demand associated with air-conditioning in most industrialized countries has been increasing in recent years. Traditional mechanical steam compression systems have been used for decades; nevertheless, it demands large amounts of electrical energy for the operation of the compressor; this energy demand not only affects the environment but also negatively impacts the user in economic terms associated with the cost of operation. Therefore, it has become crucial to design air-conditioning systems that are respectful to the environment and are capable of operating using waste or renewable energy sources. Commercially available absorption chillers for air-conditioning applications usually operate

O mixture and use steam or hot water as the heat source [1]. It has been testified that

economic, and environmental points of view. They are only competitive when using waste or renewable heat as part of the driving energy [2]. Besides, according to the operating temperature

being powered by ordinary flat-plate or evacuated tubular solar collectors. The main advantages of solar absorption cooling systems concern the reduction of peak loads for electricity utilities, the use of zero ozone depletion impact refrigerants, the reduction of primary energy consumption, and the reduction of global warming impact [3, 4]. Cold production through absorption cycles has been considered one of the most desirable applications for solar thermal energy.

**2.1. Determination of the working operation time of the absorption cooling system**

An analysis of the environmental temperature was carried out in order to select the operation time of cooling absorption system. The TRNSYS software was used to simulate the building because it has implemented meteorological data such as radiation, environmental temperature, wind velocity, and so on for different cities around the world. **Figure 1** shows environmental temperature and global radiation profiles along a year (0–8760 h) at Temixco city, Mexico. The selected period was from March to May (1460-3560 h) to operate absorption

The TRNSYS software has the advantage to simulate different kinds of processes (called types) such as pumps, photovoltaic modules, solar collectors, controllers, buildings, among others, and they can interact with each other with the environment in a dynamic way along time. The heat generation of the building considers four people in a rest position and three computers turned on from 8:00 to 18:00. Dimensions and main building characteristics are shown in **Table 1**.

O absorption units using fossil fuels are not competitive from the energy,

O absorption chillers have the advantage of

**Figure 3** shows the behavior of environmental and building temperatures and relative humidity, as it can be seen 25°C was the set point temperature of the building. The relative humidity varied from 20 to 83%.

**3. Structural conditions of construction**

market. The following structural materials were revised.

the position in floor or ceiling, is in a range from 3.5 to 4.2 kN/m<sup>2</sup>

**3.1. Structures of wood**

support 2 kN/m2

**3.2. Structures of reinforced concrete**

Advantages - Thermal low

**Table 2.** Comparison of structures.

Disadvantages - Irresolute and destroyed for

1.5–2.2 kN/m<sup>2</sup>

or fracture [5].

high cost [6].

It is so important to consider structural conditions for the installation of absorption system, for example, loads or static, dynamic and cyclical forces, the mechanical properties that it must satisfy are resilience, tenacity, ductility, and resistance to the deformation. The structures of materials are considered to accomplish the requirements that are available in the

The main advantages are di-electrical materials or natural insulation, seismic resistance, and they are cheap in comparison with the girders of reinforced concrete. Nevertheless, they can be attacked and destroyed by insects, by fungi, and by natural rot; in addition, they are not resistant to the fire. The weight capacity of structures of wood support, according to

wood type 2, the wood structures support from 1.5 to 2.2 kN/m2, before suffer deformation

The characteristics of the reinforced concrete are as follows: it increases the rigidity and offers the possibility of completing the build later. The structure is formed per rigid knots and nondeformable edges. The disadvantages are low capacity acoustic and thermal insulation and

**Structure Wood Metallic Concrete**

Loads 420 kN/m<sup>2</sup> >350 kN/m<sup>2</sup> >350 kN/m<sup>2</sup>


insects, for fungi, and for the rot. - It is not resistant to the fire - the weight that can load 2 kN/m<sup>2</sup> they are of the same structure to load

of useful load before suffering a deformation or fracture. Considered the

Design and Construction for Hydroxides Based Air Conditioning System with Solar Collectors…



; this means that they can

http://dx.doi.org/10.5772/intechopen.72188

47


isolation



**Figure 4** shows the behavior of cooling capacity of the building. The total energy consumed was 1.29×107 kJ from March to June. The maximum heat load capacity was 2.8×10<sup>4</sup> kJ/h (7.8 kW), and this value should be dissipated by the evaporator from absorption cooling system.

**Figure 3.** Indoor conditions of the building from 1417 to 2337 h (March).

**Figure 4.** Cooling capacity profiles of the building from March to June.
