ENERGY EFFICIENCY OF SOCIAL HOUSING IN NORTH-CENTRAL MEXICO. EXISTING GOVERNANCE AND POTENTIAL FOR DESIGN IMPROVEMENT IN A DRY-HOT CLIMATE

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UNIVERSIDAD AUTÓNOMA DE SAN LUIS POTOSÍ

FACULTADES DE CIENCIAS QUÍMICAS,INGENIERÍA YMEDICINA

PROGRAMAS MULTIDISCIPLINARIOS DE POSGRADO EN CIENCIAS AMBIENTALES

AND

COLOGNE UNIVERSITY OF APPLIED SCIENCES

INSTITUTE FOR TECHNOLOGY AND RESOURCES MANAGEMENT IN THE TROPICS AND SUBTROPICS

ENERGY EFFICIENCY OF SOCIAL HOUSING IN NORTH-CENTRAL MEXICO. EXISTING GOVERNANCE AND POTENCIAL FOR DESIGN IMPROVEMENT IN A

DRY-HOT CLIMATE.

THESIS TO OBTAIN THE DEGREE OF

MAESTRÍA EN CIENCIAS AMBIENTALES

DEGREE AWARDED BY

AND

MASTER OF SCIENCE

TECHNOLOGY AND RESOURCES MANAGEMENT IN THE TROPICS AND SUBTROPICS

IN THE SPECIALIZATION: RESOURCES MANAGEMENT

DEGREE AWARDED BY COLOGNE UNIVERSITY OF APPLIED SCIENCES

PRESENTS:

ANALEE CAMPA ELIZONDO

CO-DIRECTOR OF THESIS PMPCA: GREGORIO ÁLVAREZ FUENTES

CO-DIRECTOR OF THESIS ITT: JOHANNES HAMHABER

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FACULTADES DE CIENCIAS QUÍMICAS,INGENIERÍA YMEDICINA

PROGRAMAS MULTIDISCIPLINARIOS DE POSGRADO EN CIENCIAS AMBIENTALES

AND

COLOGNE UNIVERSITY OF APPLIED SCIENCES

INSTITUTE FOR TECHNOLOGY AND RESOURCES MANAGEMENT IN THE TROPICS AND SUBTROPICS

ENERGY EFFICIENCY OF SOCIAL HOUSING IN NORTH-CENTRAL MEXICO. EXISTING GOVERNANCE AND POTENCIAL FOR DESIGN IMPROVEMENT IN A

DRY-HOT CLIMATE.

THESIS TO OBTAIN THE DEGREE OF

MAESTRÍA EN CIENCIAS AMBIENTALES

DEGREE AWARDED BY

AND

MASTER OF SCIENCE

TECHNOLOGY AND RESOURCES MANAGEMENT IN THE TROPICS AND SUBTROPICS

IN THE SPECIALIZATION: RESOURCES MANAGEMENT

DEGREE AWARDED BY COLOGNE UNIVERSITY OF APPLIED SCIENCES

PRESENTS:

ANALEE CAMPA ELIZONDO

GREGORIOÁLVAREZFUENTES

JOHANNES HAMHABER

F.ADRIANMORENOMATA

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PROYECTO REALIZADO EN:

PROGRAMA MULTIDISCIPLINARIO DE POSTGRADO EN CIENCIAS AMBIENTALES

AGENDA AMBIENTAL

UNIVERSIDAD AUTÓNOMA DE SAN LUIS POTOSÍ

CON EL APOYO DE:

DEUTSCHER AKADEMISCHER AUSTAUSCH DIENST (DAAD)

CONSEJO NACIONAL DE CIENCIA Y TECNOLOGÍA (CONACYT)

LA MAESTRÍA EN CIENCIAS AMBIENTALES RECIBE APOYO A TRAVÉS DEL PROGRAMA

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Erklärung /

Declaración

Analee Campa Elizondo:

Matri.-Nr. / N° de matricula: 11081418 (CUAS), 0191544 (UASLP)

Ich versichere wahrheitsgemäß, dass ich die vorliegende Masterarbeit selbstständig verfasst und keine anderen als die von mir angegebenen Quellen und Hilfsmittel benutzt habe. Alle Stellen, die wörtlich oder sinngemäß aus veröffentlichten und nicht veröffentlichten Schriften entnommen sind, sind als solche kenntlich gemacht.

Aseguro que yo redacté la presente tesis de maestría independientemente y no use

referencias ni medios auxiliares a parte de los indicados. Todas las partes, que están

referidas a escritos o a textos publicados o no publicados son reconocidas como tales.

Die Arbeit ist in gleicher oder ähnlicher Form noch nicht als Prüfungsarbeit eingereicht worden.

Hasta la fecha, un trabajo como éste o similar no ha sido entregado como trabajo de tesis.

San Luis Potosí, den /el : 08/08/2012

Unterschrift / Firma: ______________

Ich erkläre mich mit einer späteren Veröffentlichung meiner Masterarbeit sowohl auszugsweise, als auch Gesamtwerk in der Institutsreihe oder zu Darstellungszwecken im Rahmen der Öffentlichkeitsarbeit des Institutes einverstanden.

Estoy de acuerdo con una publicación posterior de mi tesis de maestría en forma completa

o parcial por las instituciones con la intención de exponerlos en el contexto del trabajo

investigación de las mismas.

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Acknowledgment

I would like to give my sincere gratitude to my professors who with time and generosity share their knowledge and experiences with us every day. Especial thanks to my supervisors: Prof. Johannes Hamhaber, Prof. Gregorio Alvarez and Prof. Adrian Moreno. I would like to thank to the German Academic Exchange Service (DAAD), and the Consejo Nacional de Ciencia y Tecnología (CONACYT) for the financial support during my studies in México and Germany which allowed me to have this precious experience of living in another country and knowing all the amazing people that I love and will never forget. I would like to thank also the people interviewed for the development of this thesis; for the time and patience in sharing their experience and answering every question regarding their work and their lives.

I want to give all my gratitude to my family and friends, for their support during my studies; especially to my husband Sergio and my parents David and Maria de Jesus for the encouragement and understanding given every day during the past two years and most of all for the confidence that they all have in me.

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Abstract

Energy efficiency is an essential element of environmental sustainability. The building sector is a key element among all sectors in different economies in the world. Several factors are involved in energy efficiency, which is why analyzing the governance between the different stakeholders in the sector is necessary to identify the most important elements involved in achieving this goal locally. This study aims at the proposal of a more energy-efficient social housing in the city of Torreon, located in north-central Mexico, through the integration of the concepts of Bioclimatic Architecture in the social housing market promoted by the Federal Government through the existing sustainable housing programmess and the integration of the interests of the main stakeholders in the housing market in the country. The purpose of this proposal is to reduce greenhouse gasses emissions, reduce energy consumption of the low-income families and government subsidies to electricity bills, promoting the improvement of quality of life of End users.

Keywords: Energy efficiency, governance, social housing, bioclimatic architecture.

Resumen

La eficiencia energética es un elemento esencial de la sustentabilidad ambiental. El sector de la edificación es clave entre todos los sectores en las distintas economías existentes en el mundo. Diversos factores intervienen en la eficiencia energética; por esta razón analizar la gobernanza entre los diferentes actores relacionados con el sector es necesario para identificar los elementos más importantes que intervienen a escala local en el logro de esta meta. Este estudio está dirigido a la propuesta de una vivienda social más eficiente en el uso de la energía en la ciudad de Torreón ubicada en norte-centro de México, través de la integración de los conceptos de la Arquitectura Bioclimática a la vivienda social promovida por el Gobierno federal mediante de los programas de vivienda sustentable existentes, así como la integración de los intereses de los principales actores relacionados con el mercado habitacional del país. El propósito de esta propuesta es reducir las emisiones de gases efecto invernadero, reducir el gasto energético de las familias de bajos recursos y los subsidios del gobierno a las cuentas de electricidad, promoviendo una mejora en la calidad de vida de los usuarios finales de las viviendas.

Palabras clave: Eficiencia energética, gobernanza, vivienda social, Arquitectura bioclimática.

Zusammenfassung

Energieeffizienz iste in grundlegendes Element der nachhaltiger Umweltstandards. Der Baubereich ist ein bedeutender Bestandteil aller Wirtschaftszweige weltweit. Verschiedene Faktoren haben Einfluss auf die Energieeffizienz. Aus diesem Grund ist es notwendig, die Governance zwischen den verschiedenen Akteuren des Sektors zu analysieren, um die wichtigsten Elemente zu identifizieren, die auf lokaler Ebene eine Rolle spielen, um dieses Ziel zu erreichen. Die vorliegende Studie hat das Ziel, einen Vorschlag für energieeffizienteren sozialen Wohnraum in der Stadt Torreon im Norden Mexikos zu unterbreiten. Dies soll erreicht werden durch die Integration einer bioklimatischer Architektur mit sozialem Wohnraum, basierend auf bereits existierenden Programmen für sozialen Wohnraum, die durch die staatliche Regierung gefördert werden, sowie die Integration der Interessen der Hauptakteure des Wohnungmarktes. Ziel dieser Studie ist es, die Emissionen von Treibhausgasen zu reduzieren und den Energieverbrauch von Familien mit geringen Einkommen sowie die staatliche Förderung von Energierechnungen, um zu einer verbesserten Lebensqualität der Wohnungsendnutzer beizutragen.

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List of Figures

Figure 1: Bioclimatic design model………15

Figure 2: Final energy consumption by sector ………..28

Figure 3: Structure of GHG emissions by sector………28

Figure 4: Final consumption by energy source in Residential, commercial and public sector………..29

Figure 5: Final energy sources in the urban housing sector in Mexico………..30

Figure 6: Housing acquisition statistics 1973-2009………...33

Figure 7: Housing provision system………...35

Figure 8: Thermal comfort perception of the sample during the hot season………..45

Figure 9: Thermal comfort perception of the sample during the cold season………45

Figure 10: Thermal comfort diagrams per month. 1st Semester………46

Figure 11: Thermal comfort diagrams per month. 2nd Semester………47

Figure 12: Knowledge about climate change among end-users……….48

Figure 13: Energy saving measures most common among end-users………49

Figure 14: Public policy in the housing sector in Mexico………..53

Figure 15: Number of Green Mortgages offered by INFONAVIT 2009………...55

Figure 16: Different scenarios of emissions for newly built houses in Mexico……….57

Figure 17: Sustainable housing criterion of INFONAVIT……….58

Figure 18: Difference among both systems………73

List of Images

Image 1: Energy exchanges between natural and built environment……….22

Image 2: Places on earth characterized by having a dry-hot climate……….22

Image 3: Examples of architecture responding to a dry-hot climate………..23

Image 4: Mexican territory, location of Torreón………....38

Image 5: Sunpath from January to June……….39

Image 6: Sunplath from July to December……….40

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Image 9: Examples of Vernacular Architecture of social housing in the region. Ejido Pilar………42

Image 10: Examples of Vernacular Architecture of social housing in the region. Ejido la Joya………42

Image 11: Social Housing settlements………44

Image 12: Climate zones in Mexico according to the NAMA and locations of the buildings for calculations.56 Image 13: Architectonic proposal. Floor area 1……….67

Image 14: Architectonic proposal. Floor area 2……….68

Image 15: Architectonic proposal. Elevations………69

Image 16: Architectonic proposal. Sections………...70

Image 17: Front view-Floor area 1……….71

Image 18: Rear view-Floor area 1………..71

List of Tables

Table 1: Energy consumption in the Residential, commercial and public sector, 2010……….29

Table 2: Monthly average hourly temperatures estimation from extreme mean………….………...38

Table 3: Monthly average hourly relative humidity estimation from extreme mean……….………39

Table 4: Bioclimatic elements of vernacular popular homes in the region of La Comarca Lagunera………...43

Table 5: Requirements diagram ………48

Table 6: Number of inhabitants per house and energy consumption………49

Table 7: Area analysis………51

Table 8: Minimum wage and additional credit for Green Mortgage measures………..54

Table 9: Information matrix………..63

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CHAPTER 1: INTRODUCTION

1.1. Introduction

During the last few years the Mexican government has joined international efforts in the quest for energy security and a way to care for natural resources by creating a model of sustainable living in different areas. The building sector is one key sector, through the incorporation of sustainability measures in the housing market, specially social housing, in 3 main programmes; “Green Mortgage” (HV), “This is your House” that work together to provide more funding for workers (CONAVI, 2010) and The Supported NAMA for Sustainable Housing in Mexico (CONAVI, SEMARNAT, 2011).

Besides the original objective, the model has also the purpose of providing a better life quality for users, through the integration of policies for the efficient use of resources, including energy efficiency measures, as energy is an overriding element of sustainability

(Richarz et al, 2006) and the introduction of other social concepts1.

However, up until now; this objective has not been achieved due to the nature of the relationship between the different actors involved in the field of social housing in the country. Different objectives and the lack of knowledge on the subject by all stakeholders have become the obstacles to improve energy performance in this sector.

The housing sector in Mexico accounts for 20% consumption of the country's final energy, along with commercial and public sectors (SENER, 2011). The residential sector has expanded since the 1990’s (Monkkonen, 2009) followed by the increase in energy consumption. The energy savings potential is significant due to the expansion that has characterized the sector and the projections for future growth.

The regions that show higher energy consumption in the country are characterized by having a hot climate. The city of Torreón, located in the State of Coahuila in the North-center of the country, is one of them, where social housing occupies 56% of the city´s surface and 86.6% of electricity is destined for domestic consumption (PDDU 2002). From this fact arises the need for further study to implement energy efficiency measures in this sector that can generate savings in household spending and government subsidies in energy while preventing GHE emissions into the environment.

In order to contribute to the design of a more energy efficient proposal design, in addition to follow a methodology that integrates the interests of different stakeholders, this study has focused on the review of energy efficiency policies integrated into the social housing market through existing institutions and programmes in Mexico and discussed the housing sector governance.

1

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1.2. Contributions of this study

Considering that 50% of final energy is consumed by air conditioning systems to achieve thermal comfort in homes located in regions characterized by hot and extreme climates in the Mexican territory, further study is needed to find the most effective and appropriate measure to accomplish better comfort levels according to the characteristics of each region. (Martínez, 2009,)

The existing housing policy at the national level, presented in Chapter 4 of this study, is an important step to fight climate change and complying with international agreements of GHG emissions and achieve thermal comfort specially in social housing, however, the proposed measures in the main programmes are technological and mitigating measures that require more investment aside to housing costs and do not integrate the regional elements of architectural design.

In addition in the programmes implemented to date in Mexico, the focus on the isolation of the building envelope to improve thermal comfort conditions indoors, following trends in the European Union and other regions with different climatic characteristics, belittle other viable options that can help accomplish the same goal more effectively. The homogenization of the efficiency measures all over the world can become an obstacle on the path to achieve the objectives established (Mingozi, 2009).

A comprehensive design, appropriate to the regional conditions such as climate, materials, and architectural background, although is mentioned in the proposals, it is not mandatory for developers to implement. It becomes then a lost opportunity to use a cost-effective measure that can benefit the three main stakeholders in the housing market in Mexico characterized by less investment in technology, lower subsidies for housing, energy efficiency gains and the creation of better house in terms of thermal comfort.

This study aims to provide a proposal of a bioclimatic social housing design, located in

the city of Torreon, Coahuila. The design has been developed through an evaluation of the Mexican policies of the social housing market, the different interests of the three main stakeholders of this sector, the relationships among them and the study of the characteristics of the region. The research questions that this study aims to answer are:

 How can more efficient homes in the context of a dry-hot climate be achieved?

 How can a family´s life quality be improved through the home-energy nexus?

 What is the role of governance and market stakeholders in the social housing sector

in Mexico?

1.3. Conceptual Framework

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country and/or culture. It is a concept that needs a mix of measures such as regulations, tax incentives, material production, technology development, adequate design and maintenance passing through all the stakeholders involved in the building industry from the highest levels of government to the end user of the building whether the owner or the tenant (UNEP, 2011).

The following are some key factors that can influence the achievement of energy efficiency in this sector:

 The environment has a significant influence on the nature of building and their energy demand; in fact it is “a fundamental part of the design process” (Fuentes, 2000). The application of bioclimatic principles such as: latitude, ambient, temperature, sun hours and building characteristics are crucial elements in the reduction of energy demand and GHG emissions (Poulous, 2004).

 Cultural factors and the way people perceive energy is truly important. In addition

to using energy as an indicator of social status, there are deeply entrenched attitudes and practices of how people establish patterns of comfort and efficiency.

 The concept of thermal comfort can vary from one place to another. Although there are overall evaluations of the human comfort level, this concept has much to do with customs, environment, adaptability (OLGYAY, 2008) and even age and gender of people. Establishing an adequate level of comfort and an energy use indicator is crucial to set performance standards for buildings. Energy efficiency needs an understanding of what people can endure; how much energy they are willing to pay and also on how much people are willing to make changes in their behavior patterns: in the way they experience comfort or the actions they take to make a more efficient use. Energy efficiency requires a more proactive attitude by the user in relation to the environment and this will reflect the degree of active or passive strategies that should be implemented in the building as efficiency measures. (UNEP, 2011)

 Another important factor is “the fragmented approach to building energy use”

(WBCSD, 2007). Markets have different characteristics in each country; integration among the value chain is usually fragmented. In addition end-users are the ones that can directly beneficiate from energy savings but may not have the financial or technological capacity to make the necessary investments on energy efficiency measures (WBCSD, 2009) which is the case of the Mexican social housing market. Additionally, they are not generally consulted on what would work for them (WBCSD, 2007). Therefore it is important to integrate this important stakeholder to the design process directly asking for their requirements and by doing so designing a house that can be more valued by its inhabitants.

 Energy increase in the building sector is generally related to economic

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lifestyles of end-users in any socioeconomic status. This relation must be broken proving that it is possible to find comfort and wellbeing levels following a more energy efficient path making energy more valued by all involved in its use and the decision in the investment process (WBCSD, 2007).

In addition, to achieve energy efficiency in this sector appropriate policies and

regulatory frameworks are necessary. These elements such as legislation and regulation,

financing options and incentives, information and training on energy must be transparent, appropriate to each country, clear and aiming towards the same goal (UNEP, 2011) (WBCSD, 2009).

The list of interrelated factors makes the search of different approaches and methodologies for the development of more comprehensive and integrated projects necessary, in order to achieve the goal of energy efficiency in each of the levels of the sector according to the needs of all involved. Bluyssen, (2010) proposes the use of an integrated approach that considers all factors. According to UNEP, (2011) and WBCSD (2007), the best opportunity to achieve energy efficiency is integrating Bioclimatic Architecture into the building during the early stages of the design process. To achieve this, it is necessary to develop a multidisciplinary approach of integral design.

A multidisciplinary approach of integrated design refers to the continuous feedback of the different factors, disciplines and stakeholders involved in the development of a building. This process occurs at the conception of the building, when the designer determines the building components, according to weather and location. Designers, supported by industrial engineers with the development of suitable materials should make the best decisions on materials, especially for the building envelope, taking into account the regulatory framework, standards and production costs.

The model followed in this study for the development of the design proposal for an energy efficient house is based on a methodology for bioclimatic design proposed by Fuentes,

(2008)2. This model was modified to achieve the integration of the 3 main stakeholders

involved in the housing market in Mexico: end users, developers and the government.

The aim of this model is to study the requirements of each stakeholder and then integrate them into one approach that later becomes the design proposal. This model is very clear about the variables needed for bioclimatic design. In addition, the transparency about the requirements allows identifying the information inputs and outputs needed for the creation of the matrix that help in the design process of the proposal.

2

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In the model proposed by Fuentes, it is possible to find more of the variables involved in the energy performance of buildings. For the purpose of this study, the model was modified considering only those aiming to achieve thermal comfort inside the building in order to avoid unnecessary use of mechanical means for air conditioning and thus reduce the final energy consumption.

Figure 1: Bioclimatic design model (Author based on Fuentes, 2008)

The model used, presented in Figure 1, contains 4 main variables: environment, end-user,

government and developers. These variables are equally important and are subdivided into 2, representing different dimensions, according to the nature of each variable, located in row 2 of the diagram.

The boxes located in the third row represent the key information that will be analyzed for each variable. The product of the information analysis is located on the fourth row. With this product, an information matrix was developed; this matrix was combined with the economic dimension that determines the housing conditions for the 3 stakeholders involved.

The information flows among the matrix and the available bioclimatic design strategies that can be used to develop the prototype. Later, these design strategies were combined with the economic dimension in order to identify the best strategy in terms of economy.

In order to clarify the issues that this study addresses, it is important to explain the following concepts:

The concept of Social housing in this study refers to a building with a cost no more than

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housing is addressed to employees with an income of 1 to 3.9 minimum wages and it´s design must provide the option to grow progressively (Maycotte, 2005).

The term Energy Efficiency refers “to reduce energy consumption for acceptable levels of

comfort, air quality and other occupancy requirements” (WBCSD, 2008). This means all aspects of energy must be considered such as:

 End-users/owners: behavioral patterns, , basic and comfort requirements

 Developers: architectural trends, bio-climate, regionalism

 Government: financial schemes, regulations and monitoring.

 All stakeholders: cost-effectiveness, materials, technology, market characteristics

and general awareness.

Governance is a process of connection among different stakeholders each one with special

interests, in an international or local context with the purpose to generate certain regulation regarding the solution of problems (Clausen, 2011). This process is a key element to achieve energy efficiency especially in the building sector because of the market characteristics and the differences among the stakeholders involve.

Bioclimatic architecture is currently defined as the one that "takes into account climate and environmental conditions to help ensure comfort, indoors and outdoors, and that uses mechanical systems, which are considered only as support systems "(ANES, 2006). This architecture has been used since the origins of man to "satisfy two basic human needs: protection from the elements and providing a space with a favorable atmosphere for the

spiritual gathering" (Olgyay, 2008). However, the term Bioclimatic Design was proposed

by Olgyay brothers until the middle of the 1960’s decade. This concept is one more element that can be integrated in the sustainability model (ANES, 2006).

1.4. Background and Scope

Different models that aim to develop energy-efficient buildings have been developed over the past 40 years; however, the field of implementation is still growing (UNEP, 2011) In México different researchers have also worked on bioclimatic architecture since the 60's, mainly in academic institutions in the center of the country. An important group with 30 years of experience in UNAM is comprised of David Morillón, Diego Morales, Ernesto Jauregui and Adalberto Tejeda and Victor Fuentes Freixanet.

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The Universidad Mexicana del Noreste has worked on studies of the thermal design of dwellings located in the north of the country, that aimed at preventing heat gains through the integration of different materials.

Moreover, in the state of Sonora the participation of a group of researchers in the same subject formed by Manuel Ochoa, Irene Marincic, Guadalupe Alpuche, Benito Perez and Ana Bourbon is highlighted (ANES, 2006).

The cities of Torreón and Mexicali, characterized by having a dry hot and extreme climate, were the subject in 2003 of a study conducted by the National Institute of Ecology (INE). The study consisted on evaluating the energy efficiency of air conditioning systems suggested for the “Hipoteca Verde” programme through the measurement of the energy performance of the housing units. For the city of Torreon in the area of air conditioning, there were no conclusive results as the typical air conditioning system used is not among the measures recommended in this programme, however considering all the characteristics of the city’s climate, bioclimatic features in the development of the design, was a recommendation of INE´s study in 2006.

Daniel Solis (2010) studied various northern cities of the country: Mexicali, Nuevo Laredo, Monterrey, Hemosillo, Chihuahua and Torreón to analyze the thermal behavior of social dwellings in different configurations of orientation and shading. This study was helpful in choosing the best orientation integrating the concept in bioclimatic design. He concluded that orientation has a great effect in thermal behavior of these dwellings and that the best orientation is North-south.

The present study focused only on the social housing sector in Mexico subsidized through government institutions. The informal housing sector is not considered due to differences between the two sectors; however, it is important to propose a study conducted in the informal sector considering that this sector accounts for 30% of the Mexican housing market (Monkkonen, 2009).

It is important to recognize that energy efficiency can be achieved through improvements in different areas in buildings and in cities morphology: from the manufacture of materials, during the building process, lighting, appliances including air conditioning, water heating, envelope and application of renewable energy etc. This study focused only on the building design integrating bioclimatic concepts to play with the features of the environment and achieve greater thermal comfort.

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1.5. Thesis Layout

This study consists of 6 chapters; in the first of them, there is the introduction with the model that will be followed throughout the whole study.

Chapter 2 examines options for achieving energy efficiency in the building sector, the world perspective, existing models to generate a better use of energy resources, the principles of bioclimatic architecture and the barriers to implementation of energy efficiency measures.

In Chapter 3 there is a review of the history of the housing market in Mexico, with the purpose of finding the bases to the existing relationship among stakeholders.

In Chapter 4 it is possible to find the features, views and interests of the 3 main

stakeholders involved in the social housing sector in Mexico: government, developers and

end users and the characteristics of the study area. These issues are needed to identify the requirements and demands of the stakeholders for the creation of an information matrix dedicated to the development of the final product of this study.

Chapter 5 presents the criteria of the design proposal and the presentation of architectural plans.

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CHAPTER 2: ACHIEVING ENERGY EFFICIENCY IN THE

BUILDING SECTOR

2.1. World Perspective

Energy security and environmental degradation related to energy consumption are two major challenges that humanity has faced for years. This is especially important in cities where 50% of the total world population lives and reaches 7 billion inhabitants (UN, 2011). Cities consume 60 - 80% of total world energy production causing approximately the same amount of greenhouse gases (UNEP, 2011).

The world population will increase to 9.3 billion people by 2050 (UN, 2011), established mainly in urban areas and in different proportions among developed and developing countries. This growth will increase demand for resources and environmental damage. The building sector is responsible for 30 to 40% of primary energy consumption in most countries (WBCSD, 2009) and due to the steady population growth, consumption continues rising (WBCSD, 2007). It is also the largest producer of greenhouse gases (UNEP, 2011).

Energy demand in this sector is projected to increase by 60% by the year 2050. Buildings have a long life cycle and most of the energy is consumed in the occupation phase; for these reasons it has become an area where the search for new ways of achieving energy efficiency is essential (WBCSD, 2007). Electricity is the highest energy consumption source in the building sector. About 60% of the world's electricity is consumed in residential and commercial buildings. Although this consumption varies widely according to geographic location, climate and consumption patterns (UNEP, 2011).

There are important differences not only geographical, but also among developed and developing countries regarding the drivers of energy use in buildings (WBCSD, 2007). In developed countries the rate of urbanization is lower and the economy is based on the service sector as opposed to developing countries, which have a rapid urbanization and economic activities still include agriculture and industry. In addition, developed countries have a higher income, causing the demand for more single-family housing and appliances. For these reasons, developed countries are responsible for half of the demand for building-related energy and CO2 emissions.

However, this trend is changing rapidly as the population in developed countries is not expanding. In countries like Brazil, India and China where economic development is so rapid as the rate of population growth and urbanization, there is the need for a large number of buildings dedicated to housing, offices and industry (UNEP, 2011).

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appliances (WBCSD, 2007) that later cause the increase in energy consumption. Developing countries must remain aware of the path that they will follow in the use of their energy resources.

Despite the differences regarding the use of energy, this is clearly an opportunity for both developed and developing countries. Energy efficiency, in a broader concept, in addition to the benefits listed above is also a window to: boost the building sector, generate employment, create healthier buildings (UNEP, 2011) and promote equity, releasing existing resources for the government and end users to invest in basic needs other than energy supply (UNEP, 2011).

Energy efficiency has proven to be the best alternative to help meeting energy demand to the world population (World Energy Council, 2010). This concept, when made a reality, helps in the objective of ensuring energy provision with the existing technology and policies and the lowest investment costs (WBCSD, 2009). In many countries, especially industrialized countries, the implementation of energy efficiency measures in key energy end-uses such as vehicles, appliances, space heating and industrial processes (Geller et al, 2005) has helped in the reduction of their energy intensity and CO2 production over the last three decades (Expert Group of Energy Efficiency, 2007).

The building sector has also the greatest potential among the different sectors in the battle against climate change (UNEP, 2011). Through the integration of appropriate technology and policies, the building sector alone could reduce 29% of greenhouse gas emissions projections for the year 2020 without any investment at all (UNEP, 2011).

2.2. Architecture responding to the Environment: Bioclimatic

Architecture

Worldwide, nowadays, there are two major trends to achieve energy efficiency of buildings. The hight-tech design: buildings that use the latest technology and the different existing renewable energy sources, e.g.: motion sensors, sunscreens, PV systems, etc. (UNEP, 2011). The second, which is the focus of this study, is through passive systems, which when appropriate to local conditions and environmental factors they allow the generation of satisfactory thermal comfort conditions inside buildings thus reducing or eliminating the need for air conditioning systems (UNEP, 2011) making it a measure of efficient use of energy.

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There are other factors involved in thermal comfort, such as metabolic rate, clothing insulation (ASHRAE, 2004), however, and because they are personal factors are not taken into account for purposes of this study.

The air temperature is considered the main element for thermal comfort (Fernandez, 1994). It is the average air temperature around the occupant (ASHRAE, 2004). The temperature variation depends on sky conditions, if the sky is clear it allows solar radiation to expand and originates the temperature variations throughout the day.

Radiation is one of the means of solar use to facilitate the process of heating in winter and

the most important factor to protect in summer.There are 5 types of heat radiation, the most

important, for purposes of this study is the direct and diffuse solar radiation.

Air movement is important because it influences the heat loss from the skin of the occupants inside (Olgyay, 2008) and from the envelope of the building (Fernandez, 1994). Controlling the movement of wind is necessary to keep it in balance so that the air is kept in constant renewal for reasons of health, comfort and welfare avoiding rapid wind that causes unpleasant conditions.

The use of natural ventilation in the country has an average potential of up to 44% of air conditioning and heating purposes, especially in areas of the country characterized by having a hot climate (Oropeza et al, 2011).

Humidity "is a general reference to the moister content of the air" (ASHRAE, 2004). A certain percentage of moisture in the atmosphere is necessary mainly because it fulfills several functions in the body such as maintain in good conditions the mucous membranes of eyes and nose while avoiding the generation of static (Olgyay, 2008). However humidity but must be in balance because too much of it can prevent body heat loss in high temperature environments (Fernández, 1994).

Materials, depending on their characteristics and properties, store and transmit energy from the sun to the air inside the building.

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Image 1: Energy exchanges between natural and built environment. (Author based on Morillón, 2008)

Other factors involved fully in the comfort sensation are the nature of the materials, shape and orientation of buildings. This is why they must be taken into account and adapted to local conditions to achieve a better interaction with the environment (Fernández, 1994). In arid places (see Image 2) one of the most important requirements is to protect from high temperatures during the hot season. The strategies proposed by bioclimatic architecture depend on environmental and cultural factors.

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The combination of solutions are diverse in different parts of the world with these characteristics (see Image 3), however, the strategies used follow certain pattern. Examples of different solutions are:

 Compact buildings to avoid heating surface.

 The use of bulk materials for walls and ceilings such as mud-bricks, which slow

down thermal energy transfer between the inside and outside due to its high thermal inertia.

 Half buried spaces, because the ground maintains a temperature close to the mean

temperature. The envelope of half-buried spaces maintains contact with the ground avoiding environmental heat losses.

 Orientation to the south in the northern hemisphere with small openings and to

north in the southern hemisphere.

 High walls to create shading.

 Shade courtyards and to create a comfortable microclimate.

 Deciduous and perennial vegetation in combination.

 Ventilated vaults and domes as roofs to allow for different temperature layers in the

air carrying the hot air away from the occupants.

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2.3. Policy instruments: integrating different stakeholders

Many countries have established policies to achieve energy efficiency in different sectors. The building sector is one of the most important because it is regarded as the sector where efficiency measures will have better results long term (IEA, 2005). Developed and developing countries, according to their policies about energy and climate change, have implemented various laws establishing targets for determining the energy performance of their buildings.

In the European Union for example, reducing energy consumption has become a key factor in meeting the goals under the Energy Efficiency Project 20-20-20 as a measure to reduce energy dependence. As a consequence the Union has implemented, in the building sector, the Directive 2010/31/CE of the European Parliament and Council on the energy performance of buildings as the main legislation to achieve the energy saving potential in this sector.

This Directive promotes improved energy performance of existing and new buildings taking into account local weather conditions and indoor comfort requirements. Each Member State of the European Union has a responsibility to integrate the methodology established in this policy in their respective building codes and to establish programs and tools needed for compliance (European Parliament, 2010).

Another example, the United States, especially in the last decade, has established national and local laws related to the energy performance of buildings in the American Recovery and Reinvestment Act of 2009 (U.S. Department of Energy, 2012).

From efficiency policies in each country, different instruments of regulation and control, market based and financial are born according to the possibilities of each country in order to achieve greater efficiency.

Besides the purpose already mentioned, these policies have also the objective of boosting the growth of the market, generating utilities for developers, creating employment through new better ways in the use of resources and allowing families to enjoy a proper housing provision system.

Regulation and Control mechanisms

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Control mechanisms are needed to evaluate the development of the efficiency measures and results. These mechanisms are: energy audits, labels or energy certificates that are an extension of the building codes and can help maintain reliable information at hand in order to audit compliance with the targets and the operation of funding programs and incentives (UNEP, 2011).

Financial instruments and incentives

Subsidies and tax packages must be high enough to boost the energy efficiency market. These incentives should be provided to implement them together and along with an appropriate design of new buildings or existing buildings in the process of refurbishment.

These measures combined will provide better energy performance of the building than isolated measures (UNEP, 2011) such as Mexico with its programs of FIDE and CFE for boilers and refrigerators (CONUEE, 2012) covered in Chapter 4.

To enable these instruments to work appropriately they should generally be accompanied by structured institutions, financial instruments, a stable market and the involvement of all stakeholders (UNEP, 2011). The energy prices should be high and strong enough to encourage energy savings from users and to generate profits for the operation of these schemes but not so high to have a bad influence in the political system of the country. In the case of Mexico, as in many developing countries, energy is subsided; this issue can inhibit the motivation of end users to seek for energy savings (WBCSD, 2009).

The most common financial measures are the following:

 White certificates: have been used in Australia, France and Italy (UNEP, 2011). The

experience of trading with them has been limited, although it is expected that the market will grow over time (Lees, 2007).

 Energy Service performance contracting: Energy Service Companies (ESCOs)

develop and implement energy efficiency projects and achieve their utility through the energy savings.

 Rebates can be implemented into the tax system to provide credits to home owners

for the adoption of specific energy efficiency measures.

 Feebates are a combination of fees and rebates, allowing energy efficiency measures

to appear attractive to end users and imposing the environmental cost to those how don´t adopt the measures suggested.

 Green Mortgages are credits that allow owners to afford and apply through their

mortgages energy efficient measures in their homes; this system has been adopted by the main Mortgage loan Institution for housing in México.

 External capital is used for big or high-risk projects to share responsibilities and

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 Revolving funds that are accomplished through the energy savings from the measures implemented, that at the same time can finance more energy efficiency measures (UNEP, 2011).

 Carbon finance of the “World Bank Carbon Finance Unit (CFU) uses money

contributed by governments and companies in OECD countries to purchase project-based greenhouse gas emission reductions in developing countries and countries with economies in transition. The emission reductions are purchased through one of the CFU's carbon funds on behalf of the contributor” (World, Bank, 2012). Carbon funds have not been yet widely used in the building sector although in theory this sector represents a great opportunity for this kind of funding (UNEP, 2011).

Standards

There are several standards in the world to achieve energy efficiency in buildings apart from the existing standards regarding appliances and lighting. MINERGIE and Passiv Haus are 2 well recognized in the building industry (UNEP, 2011).

MINERGIE is supported by the Swiss Confederation, the Swiss Cantons along with Trade and Industry and it is registered in Switzerland. Comfort and efficient final energy use are the main objectives of this brand achieved by special building envelopes and the continuous renewal of air (MINERGIE, 2012).

Passiv Haus is a standard aimed at achieving energy efficiency of buildings and interior comfort in an affordable way. This Standard was first developed in Central Europe and has spread all over the world including in hot climates. This standard can achieve energy savings up to 90% using a mix of measures: “efficient use of the sun, internal heat sources and heat recovery, rendering conventional heating systems unnecessary throughout even the coldest of winters” and passive cooling techniques (Passive Haus Institute, 2012). The key elements of the Passive Haus criteria are:

1. Building envelope: all spaces inside the building must be hightly insulated.

2. Airtightness : avoid air leakage through unsealed joints

3. Ventilation: use a mechanical system that can warm the cooler air commig in with

the hot air leaving the building.

4. Thermal “bridges” : eliminate heat losss from poorly insulated points in some

components of the building envelope such as windows and doors.

5. Windows: avoid heat gain in summer and heat loss in winter (WBCSD, 2007).

2.4. Barriers to achieve energy efficiency

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According to UNEP, (2011) there are different kinds of barriers for energy efficiency in the building sector:

Economic or financial:

 Lack of resources for incentives or split incentives when returns from energy

savings are not clear and not reaching any of the involved stakeholders.

 Market failures in the case of high-risk projects or low energy prices that take away

motivation to improve the energy performance.

 Investments cost that in first analysis seam very high against the pay-back period.

 Lack of financial capacity

Political or structural:

 Coordination between the different stakeholders; their responsibilities and rights

among stakeholders with diverse interests, meaning the lack of a governance

process in a mayor barrier to implement energy efficiency measures.

 Lack of knowledge and lack of leadership. (WBCSD, 2007)

Behavioral:

 The nexus energy-progress, as mentioned before is an important factor related to

economic development in many countries. A higher income generally manifests in the acquisition of more appliances and the requirement for higher levels of comfort.

 Lack of interest and awareness on energy-environment issues is an important

element to consider when asking a certain population to change their habits. It is necessary that people to change way they perceive energy and the environment in order to modify the way they use it.

2.5. Conclusions

Energy efficiency is a concept that has many dimensions: economic, social, cultural and technological. It is necessary to properly integrate these factors in each dimension that can help achieve the goal and visualize the potential impact of each step taken long term.

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CHAPTER 3: CHARACTERISTICS OF THE SOCIAL

HOUSING MARKET IN MEXICO

3.1. Energy and GHG in the housing sector

Housing has been recognized as a key sector in the structure of energy demand (CONAVI, 2008,) of the country because it is responsible along with the commercial and public sector of 20% of final energy consumed (SENER, 2010), as shown in Figure 2.

Figure 2: Final energy consumption by sector. (SENER, 2010)

In a more profound approach it is possible to deduce the importance of the sector, when an evaluation of the growth to date and projected growth for the near future is made. By 2030, there will be 45 million homes (CONAVI, 2008). It will be necessary to build from 800,000 to 1 million homes per year over the coming decade in the country (CONAVI-SEMARNAT, 2011).

Additionally, the housing sector in the country directly causes 4.9% of the emissions of Greenhouse Gases (GHG) (SENER, 2010), as shown in Figure 3; due to direct generation in addition to the amount generated by the electricity consumed in this sector , which make a total of 7% (CONAVI-SEMARNAT, 2011 ).

Residential, comercial and public 20%

Transport 48%

Industy 29%

Agriculture 3%

Industry 14.8%

Residential 4.9%

Agriculture 2.0%

Comercial and public 1.2%

Power Generation Industry 10.4%

Electricity generation 28.2%

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More than 90% of the final energy used in Mexican households comes from fossil fuels (Morillón, 2011). The energy sources most commonly used in the housing sector are primarily gas and electricity as shown in Figure 4. To the year 2030 more than 11 million homes will be built, “contributing as much as 33 Mt CO2 to the cumulative GHG emissions to the country’s carbon footprint” (CONAVI-SEMARNAT, 2011)

Figure 4: Final consumption by energy source in Residential, commercial and public sector. (SENER, 2010)

Table 1: Energy consumption in the Residential, commercial and public sector, 2010 Source: SENER, 2010

Electricity is the second most widely used energy source in this sector and as Table 1 shows, in the last 10 years, electricity has been rising steadily unlike other energy sources.

Liquified gas 38.4%

Wood 28.5%

Electricity 27.8%

Dry gas 4.1%

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An analysis of the uses that the population gives to energy is necessary in order to understand its behavior inside the buildings, in this case, inside dwellings. By doing this it is easier to identify the elements and functions that consume more energy as well as areas where the implementation of prevention or mitigating measures will be cost-effective (CONAFOVI, 2006).

In the case of the residential sector in Mexico, 4 different areas have been identified shown in Figure 5. These areas are subjects of measures implemented in 2009 directing towards sustainability.

Figure 5: Final energy uses in the urban housing sector in Mexico (Author based on Oropeza et al, 2011)

3.2. The social housing market in Mexico

The building sector in the world is characterized by fragmentation among the different sections of the market, from production to acquisition including maintenance (WBCSD, 2007). The social housing market in Mexico is not different, however, this feature is a key element to understand the relationships and dynamics among the different stakeholders involved in this sector and that are the subject of this study.

In order to understand the social housing sector in Mexico, it is necessary to take a look at the housing provision system in the country. This system defines existing funding policies, the characteristics of the stakeholders involved and the common building systems, shaping the morphology of the cities and determining environmental issues related to it (SHF, 2012).

In the history of housing supply in the country it is possible to distinguish 6 phases:

Phase 1:

Since the birth of Mexico as a country, due to the characteristics of a society under the feudal system and especially in rural areas, and the urban fringe, the low-income population built their homes with the most handy and cheap resources. The population remained under

Air conditioning 36%

Warming 8%

Ilumination and appliances 33%

Refrigeratior 14%

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the system of self-financing and self-help using traditional materials like clay, masonry, wood and mud bricks.

In the center of cities, the existing homes were usually private buildings available for rent that were increasingly overcrowded characterized by high rents without control by local authorities.

This stage is characterized by a high participation of the community in the provision of

housing. This architectural expression, now known as Vernacular Architecture3, was built

with regional characteristics both in terms of cultural expression and the inclusion of climatic conditions and resources of the region concerned.

Phase 2:

In 1924, the first organization dedicated to funding and building social housing was born in response to the social movements demanding a solution of the housing problems. However the birth of this institution was really a post-revolutionary political movement aimed at getting votes from the public (Villar 2007).

Since 1940, the population grew exponentially and began migrating to the cities. This phenomenon multiplied the need for housing and urban land. The government became aware for the first time of the existence of a housing deficit that should be covered through national programmes.

Several programmes and institutions such as FOVI were created to provide housing, mainly for rent. These actions were concentrated mostly in the capital of the country and were insufficient to provide housing for a growing population; however, it gave way to the birth of a national-building sector closely linked with the state (García, 2010).

Phase 3:

In 1972, the federal government in its role as promoter of urban development, set the main system housing mortgage financing existing at the present day, through the creation of the National Housing Fund for Workers (INFONAVIT) and the Housing Fund of the Institute of Security and Social Services for State Workers (FOVISSSTE). Since then, mortgage loans are aimed at the acquisition of housing that meets certain requirements: permanent materials for walls, floors and ceilings and access to water, sanitation and electricity (Monkkonen, 2009).

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This system consists on the mandatory contribution of 5% of the wages of workers as a solidarity fund in which workers with higher incomes provide the greatest amount of funds for the Institute. Thus, the Institute organizes funds for lending to all salaried workers in the country to pay over a period of 10 to 30 years (Beele-Campa, 2011).

During this period, the system was characterized by being centralized in the state; that is

to say, the funds provided for workers, the acquisition of land reserves, building, supervision and promotion of housing was done by and through these Institutes.

Phase 4:

In the 1990's the Government made a modification in housing policies following the global macroeconomic trends. The state abandoned the role it had in previous decades and became a facilitator for housing production in order to make the process more efficient. From this time, investors were integrated into the housing market in the country, generating the growth of large homebuilders nationwide and boosting the housing market in Mexico. The Government also opened the possibility for farmers to sell their lands belonging to

communities called Ejidos4. Thus large land developers were able to purchase cheap land in

order to build big housing settlements. (Siembieda et al, 1997).

Phase 5:

Since the year 2000, the state decided to give a central place to housing in the country. Thus, structural reforms were made in the housing sector policies to cover the existing housing shortage and to drive the market growth, to generate job creation and promoting housing for workers, especially for the low- income population sector (Beele et al, 2011). In 2001, with the support of the World Bank (Abhas, 2007), the Federal government created the Federal Mortgage Society (SHF) in order to provide housing for rural and urban areas through specific programmes and financial intermediaries(SHF, 2012).

This situation allowed the construction and acquisition of housing on a massive scale. Since the year 2000, the goal of the different Housing Funds such as INFONAVIT was the

adjudication of credits. Then by 2005 the priority changed focusing on the allocation of

affordable housing to lower-income population5 resulting in a record homeownership

unlike previous years as shown in Figure 6.

4

Ejido is “a juridical defined system of land tenure and land use for the community of peasants that reside on the land. It is a corporate holding system in which the users (ejidatarios) have shareholder rights. Until the Constitution reform of the article 27 in 1992, the Ejido members could not legally alienate their share holder rigths.” These reforms allowed the Ejido members to sell their land individually or as a community for other projects ((Siembieda et al, 1997).

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Figure 6: Housing Acquisition statistics 1973-2009 (Beele et al, 2011)

A major reform was the issue of the Housing Law of 2006 which distributes the responsibilities of each institution and where the National Housing Commission

(CONAVI)previously CONAFOVI was established as the federal body responsible for the

promotion of housing and meeting the goals of the Federal government (CONAVI, 2012). The Law notes that the national housing policy should also help with the access to housing for disadvantaged sectors of the population; it should consider respect for the ecological environment, the preservation and efficient use of natural resources determining appropriate criteria to climate, quality, sustainability and energy efficiency of housing (CONAVI, 2008).

The result of the housing policy until 2007 was the significant reduction in the housing shortfall, and a big expansion of the housing market making it the largest within the building sector and an important sector regarding the Total Gross Domestic Product with its contribution of 2.4% nationwide (CONAVI, 2008,).

However, and due to "the separation among the public policy at the three levels of government”, (SHF et al, 2010) this result gave way to urban sprawl that has led among other things to:

 Urban transport problems, forcing families living in remote settlements of the city

to invest a portion of their salary and time to transport to their work places; promoting pollution and the need for automobiles.

 Dormitory settlements: Housing settlements away from employment sources,

education services, and health, culture, recreation and supplies facilities.

 A high and unnecessary investment in basic infrastructure to service these

settlements away from the center of municipalities (SHF, 2012).

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 A system that continues to promote economic segregation of the population because in spite of existing programs, approximately 33% of Mexican families have no access to credit (Monkkonen, 2009).

 The emergence of large housing development companies extended at national levels

that implement their “Corporate designs”6

all over the country as a seal of the company.

Phase 6 of the housing provision systems history, which corresponds to the integration of sustainability concepts into the Mexican social housing market will be reviewed in Chapter 4 of this study.

3.3. Current housing provision system

In Mexico, there are currently a wide variety of institutions, projects and programmes dedicated to the provision of social housing; however, INFONAVIT and FOVISSTE are the main Institutions containing 2/3 of the total mortgage loans. Commercial banks are also in the mortgage market alone and with the help of some schemes from these two institutions (CONAVI-SEMARNAT, 2011). INFONAVIT is one of the main promoters of “sustainable housing” under the guidelines established by CONAVI; therefore, this study considered only the main policies of the CONAVI conducted by and throughout the Commission and INFONAVIT.

CONAVI, as already mentioned, is in charge of leading housing policies in accordance with the National Development Plan established by the federal government. These policies are reflected in the National Housing Administration.

INFONAVIT collects the funds from the taxes of workers in the country and it places them by state according to the number of employees in each one of the states. The Institute operates under policies established by the CONAVI although with its own funds. This allows the Institute to establish the criteria and characteristics that both the housing project as each housing unit must have to be eligible for funding.

Developers, depending on their scale, work with independent funds as well as with bridge loans promoted by the government as a way to boost the housing market in the country. Developers acquire land and undertake the development and construction work, plus they take care of the promotion and sale of homes and generally deliver the settlement to the municipality once they have sold all the units built.

User’s participation consists usually in choosing the desired house and the integration of the documents that are needed by developers in order to apply for the loan. The user

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acquires the loan according to their salary payable to 10 to 30 years. Once the credit is approved by INFONAVIT, the housing unit is paid to the developer. The developer has the obligation to deliver to the users; and users, through their employer, pay monthly fees to the Institute (Beele-Campa, 2011).

Every stakeholder maintains a 2 way relationship with the rest of the stakeholders involved. INFONAVIT functions as the governmental stakeholder in this system. Developers have the highest amount of work. And beneficiaries are the owners of the housing and generally the end-users although there are some cases where people acquire hosing for rent.

Figure 7 addresses the synthesized explanation of the functioning of the social housing provision system that concerns this study in order to clarify its operation.

Figure 7: Housing provision system. (Beele-Campa, 2011)

3.4. Conclusions

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Through this process, the architectural expression, manifestation of the population, has lost the regional characteristics and with this the knowledge of climatic factors affecting the thermal comfort of buildings, especially homes in the country.

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CHAPTER 4: ADCQUIRING THE INFORMATION:

REQUIREMENTS AND DEMANDS

4.1. Environment

Natural environment requirements

Methods

One section of the regional analysis of this research, that includes the characterization of site and climate classification, was made through a documentary research of historical events and through governmental sources.

The charts of temperature and relative humidity and the solar study were performed using

the software BIOSOL7.

Site characterization

Torreón is a city with just over 100 years of existence characterized by having a rapid urban growth with a population that reaches 639.629 inhabitants (INEGI, 2010). This cit y is located in North-Central Mexico (see Image 4); it is the center door to the north and the main services center within the south-west of the state of Coahuila. It is the head of the Municipality and along with the cities of Matamoros in Coahuila, Gomez Palacio and Lerdo from the state of Durango and the surrounding area form the region called Comarca Lagunera (PDDU 2001-2006).

The territory of Torreón is characterized by having a dry and hot climate (Adame, 2006). Extreme temperatures and droughts have been affecting the whole state. The hot season usually lasts about 7 months (Morillón, 2007) with temperatures reaching up to 42 ° C. On the other hand, the winter is also extreme, although it lasts only 2 to 3 months, as the temperature varies during the day and can reach -8.5 ° C (CONAGUA, 2012). The prevailing winds come from north-northeast NNE changing their directions since the month of November until February with direction from the SE (Adame, 2006). Due to these features, mechanical devices for conditioning the air inside buildings are a critical need to achieve thermal comfort for end users.

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