A low-carbon material with organic fibers for buildings

Buildings and construction sectors have a large impact on climate change, they are responsible for about 30% of total global final energy demand, and only 5% of the energy consumed inside them comes from renewable sources [1]. Moreover, heating, ventilation and air conditioning (HVAC) systems require almost 40% of the energy used in building operations to provide comfort conditions for the occupants [2]. The use of fossil fuels in the sector is responsible for 10 GtCO2 equivalent per year[1].

In Mexico, the energy consumption in buildings is 24% of final national demand, and only 1.4% comes from renewable sources [3]. The carbon emissions of this sector represents 11.7% of total annual national emissions with 24 MM tCO2e [4].

Moreover, Mexico is the second concrete producer in Latin America. This industry generates 30 million tons of CO2 in our country yearly, which represents 20% of the industrial sector and 7% of total national emissions [5].

As a country with a developing economy and growing population, it is expected that both the number of housing units and the energy demand in buildings rises in the next years; actually, 814,000 houses will be required yearly in the next two decades to meet the housing need [6]. It is also predicted that energy consumption for cooling in developing countries such as Mexico will be increased by approximately 70% by the end of the century. Furthermore, in Mexico the electricity rate in the residential sector is subsidized, which hinders the adoption of renewable energy for the needs of the occupants.

References:

[1] UNEP United Nations Environment Programme, “2022 Global Status Report for Buildings and Construction: Towards a Zero‑emission, Efficient and Resilient Buildings and Construction Sector,” United Nations Environment Programme, 2022, Accessed: Feb. 20, 2023. [Online]. Available: https://globalabc.org/sites/de...

[2] M. González-Torres, L. Pérez-Lombard, J. F. Coronel, I. R. Maestre, Da Yan, “A review on buildings energy information: Trends, end-uses, fuels and drivers,” Energy Reports, vol. 8, 2022, doi: 10.1016/j.egyr.2021.11.280.

[3] Secretaría de Energía, “Balance Nacional de Energía 2020,” Secretaría de Energía, 2020. Accessed: Feb. 20, 2023. [Online]. Available: https://www.gob.mx/cms/uploads...

[4] Secretaría de Medio Ambiente y Recursos Naturales, “Inventario Nacional de Emisiones de Gases y Compuestos de Efecto Invernadero 1990-2015 INEGYCEI,” 2019, Accessed: Feb. 20, 2023. [Online]. Available: https://cambioclimatico.gob.mx...

[5] El Financiero. (2023, Mar. 30). ‘Rechinando’ de limpias: Cementeras mexicanas acuerdan reducir emisiones de carbono [Online]. Available: https://www.elfinanciero.com.mx/empresas/2023/03/30/cementeras-mexicanas-acuerdan-reducir-emisiones-de-carbono-hacia-2030/#:~:text=Solo%20en%202022%2C%20se%20produjeron,kilogramos%20de%20CO2%20por%20tonelada.

[6] Hábitat para la Humanidad México. (2021). 14 millones de familias en México no pueden construir o comprar su casa [Online]. Available: https://www.habitatmexico.org/...

In order to fulfill the energy demand of buildings, our research group is experimentally working in the development and evaluation of low carbon building materials with organic fibers. These materials are made up of a mixture of conventional construction materials, such as cement or gypsum, microencapsulated phase change materials (PCMs), which can store/release heat without increase/decrease their temperature significantly due to their capacity of storage energy in form of latent heat, and local organic fibers.

The purpose of using PCMs incorporated in the building construction materials is to increase the thermal capacity of the mixture that can be used to develop building envelope boards at a later stage.

On the other hand, the use of organic fibers is to reduce the high impact of construction materials, which increases the life cycle of the buildings in terms of circular economy. In addition to lowering carbon emissions, the aim is to increase the mechanical strength of the new building material.

According to the National Commission for the Efficient Use of Energy in Mexico [8], just over 17% of Mexican dwellings use some kind of air conditioning system to keep thermal comfort for the occupants, which represents around 5 million housing units.

Since most of the energy needs are covered by fossil fuels, it means that the sector contributes significantly to the carbon emissions in the country. Moreover, only 5% of total housing in Mexico uses thermal insulation into the building envelope as a passive strategy to reduce the energy demand for comfort purposes [8], and only 1.8% of total dwellings are considered sustainable by their energy savings and low carbon footprint of the construction materials used [9].

Therefore the propossed solution seeks to use a waste material (organic fibers) in combination with a microencapsulated energy storage material (PCM) and conventional materials to make up a lower carbon construction material that can be applied in Mexican housing to reduce the energy requirement of air conditioned systems.

[8] Comisión Nacional para el Uso Eficiente de la Energía y Secretaría de Energía, “Refrigeración en el hogar,” Comisión Nacional para el Uso Eficiente de la Energía, 2021, Accessed: Apr. 15, 2023. [Online]. Available: https://www.gob.mx/conuee/docu...

[9] Secretaría de Medio Ambiente y Recursos Naturales,” Vivienda sustentable en México,” Secretaría de Medio Ambiente y Recursos Naturales, 2021, Accessed: Apr. 15, 2023. [Online]. Available: https://www.conavi.gob.mx/imag...

As an institution, the Instituto Tecnológico y de Estudios Superiores de Monterrey is committed to shape individuals who take responsibility for their own lives and are aware that their actions can transform others. Students and collaborators are encouraged to transform their economic, political, environmental, and social realities on a social, professional, and personal level.

On the other hand, our research group has experience working with organizations like ICLEI (Local Governments for Sustainability), a global network of more than 2,500 local and regional governments committed to sustainable urban development. The project funded by Google.org consisted in using a tool that provides environmental data, created by this company, to generate robust information and standardize the climate action plans of the Monterrey Metropolitan Area. Furthermore, people from the key municipalities were trained in the use of the tool.

In this first stage of the project our solution is currently funded to develop the low-carbon building material and test it at laboratory level, for which we have the necessary infrastructure and knowledge. The next step is to apply it in a real house and monitor its performance. For this purpose, we are collaborating with more research institutions, such as the Fraunhofer Solar Institute in Germany and the University of Ottawa in Canada.

Our solution is in a prototype stage, however only in the residential sector (where there is more available data in Mexico), the number of buildings necessary to fulfill the housing needs of the Mexican population is expected to be 814,000 per year in the next two decades. Yet, our solution has the potential to be used in non-residential buildings where the energy consumption and the need of construction materials is also high.

We decided to apply to this challenge because our solution has an important potential in the building sector and we want this project to be visible for stakeholders that are interested in contributing with our project. Also, we know this is a platform where we can meet partners that can share their experience and knowledge in technical, financial and social topics that complement our solution.

Moreover, we look for diffusion of our project and the social impact we can generate in our region.

Our solution approaches the problem in a significantly improved way because many reasons, first, PCMs included as part of buildings envelope are not commonly used and less in developed countries such as Mexico; however, when using PCM in concrete or gypsum, it reduces their mechanical properties, that is why we combine it with organic fibers.

Some positive impacts catalyzed by the integration of PCMs and organic fibers are not only the energy reduction for comfort needs in buildings but also the use of a waste material of a representative industry in Mexico. The organic fiber used comes from a Mexican industry and represents approximately 105,000 tons per year. This fiber has been previously used in other building materials but not with a thermal storage one (PCM) to improve the material mixture.

The PCM and organic fibers construction material has the capacity to change the market because it represents a solution to reduce the energy requirement of residential buildings without reducing the mechanical properties of the materials and, in the same way, it is possible to decrease the carbon impact of the final product due to less use of conventional building materials.

In the next year our impact goal is to test the low-carbon material at laboratory level and in a pilot test in a house in Monterrey, to monitor the material performance in a more realistic environment.

In five years our impact goal is to bring our solution to a commercial level, that is to generate a product applicable in houses or communities in Mexico.

In order to achieve our goals we will be looking for inversion and governmental funds that help us scale to higher TRL levels. In Mexico, institutions like the National Housing Commision (CONAVI), the Institute of the National Housing Fund for Workers (INFONAVIT) and the National Commission for the Efficient Use of Energy (CONNUE) can provide funding and promote the use of low carbon technologies in buildings through social programs and public policies.

• Number of houses/communities using our low-carbon building material in some section of the building envelope.
• Energy savings in the cooling/heating system of residential buildings.
• Carbon emissions avoided by the use of our low-carbon building material in residential buildings.
• Carbon emissions avoided by the use of the organic fiber replacing concrete in the building material.

The aim of our solution is to increase the thermal capacity of building materials that can be used to develop building envelope boards. We use PCMs, materials that at phase change temperature are capable of storing or releasing large amounts of energy while maintaining nearly constant their temperature. These materials can be applied in building envelopes to reduce their energy demand and improve thermal comfort.

In addition, to reduce the high impact of construction materials and increase the mechanical strength of the new components developed, we use organic fibers, which lower the carbon footprint of conventional building materials such as concrete.

As a team, we have the aim to include people from different countries and cultural backgrounds in our research group to foster diversity in our work. We have had people from Ecuador, Venezuela, Iran, Colombia, Germany and Mexico as undergraduate and graduate students, and professionals, working in research and technological projects. Women participation is also important for us, they have participated as students and professionals that provide valuable knowledge to our team.

To promote equity we offer the opportunity to obtain tuition scholarships and personal expenses to any student who needs financial support.

Also, we encourage our students and collaborators to lead, actively participate, and share their results with the society, scientific and industrial community as a way to promote inclusion in our team.

Our solution is in the prototype stage until now. However, the Instituto Tecnologico y de Estudios Superiores de Monterrey has wide experience in social entrepreneurship. Our institution has business incubators in different campuses that help students, collaborators and people to develop business models of their ideas. It also has a Technology Transfer Office (OTT) responsible for the protection and management of intellectual property, as well as promoting the commercialization and transfer of technology developed by the academic community. The OTT serves as a bridge between inventors and companies, entrepreneurs, and investors who are interested in developing innovative projects.

At this stage of the project, we have funds to bring our solution to the next level in a pilot application.

Our organization allocates resources to look for and apply to national and international financing opportunities. Actually, we are applying for a seed fund with the Engineering Faculty of the University of Ottawa. The purpose of this opportunity is to collaborate with a researcher with experience in PCMs to strengthen the relationship with this institution and explore more applications of PCMs with organic fibers. Furthermore, we are participating in the Scotiabank Net Zero Research Fund to promote the adoption of our material in people with housing needs.

We also have access to participate in projects with the industry that allow us to get funds and implement our technologies.

In the last six years our team has received about 380,000 USD from different institutions to support our research work. Our funders and/or the funds we have achieved are the following:

• Fondos de sustentabilidad energética by the Secretaría de Energía - CONACYT (100,000 USD).

• Fondo de acción por México by Google.org (100,000 USD).

• International Collaboration Awards by The Royal Society (80,000 USD).

• Challenge-based Research Funding Program by the Instituto Tecnológico y de Estudios Superiores de Monterrey (100,000 USD).