In present day buildings statistics have shown the negative impact of the carbon footprint. According to Architecture 2030, buildings generate about forty percent of GHG (greenhouse gases) emissions.Carbon dioxide emissions are related to the burning of fossil fuels which are used to create HVAC systems. The idea of finding more efficient ways to keep heat in buildings can reduce the amount of fossil fuels being used which in turn can reduce the amount of harmful effects being released into the atmosphere. With the continuation of our deteriorating atmosphere, there is a constant need to reuse materials that provide low-cost solutions to everyday building systems. Especially in areas with more drastic temperature differences, passive strategies are a must to reduce GHG emissions.
From the production of GHG comes a cost of not only the atmosphere but the creation of trash. The amount of trash sitting in landfills is having a harsh impact on the community and ecosystem around the world. According to the EPA the United States generateds over 257 million tons of waste each year. In order to push forward these ideas, this research investigates the performance of recycled materials in relation to thermal comfort and dehumidification.
Reimagined ideas behind insulation and the way it can be produced are being discussed in the construction/architectural fields. With the statistics about GHG and waste production, many studies are turning to the idea of reusing materials to provide thermal comfort in buildings. Through research, we have found many ideas being tested and the results of these studies. In our work we will be building off these ideas and adding our own ideas as well to contribute to the study.
In a study done by Francesco Asdrubali, Francesco D’Alessandro, and Samuele Schiavoni at the University of Perugia, they dive into the idea of using natural and recycled materials as insulators. It was found that in buildings, heating was the biggest use of energy and that had to do with the poor building insulation properties. Trying to find a more effective way to insulate buildings while also contributing to the health of the environment was one of the goals of their research. Although using specific recycled materials has not been studied in depth, the idea of sustainable design has put the idea on the map. Some of the studies they have conducted have shown that glass wastes have proved to be successful in holding heat. They also have found that although the idea behind natural insulation materials is effective, the recycled materials are better as insulators. There are still many parts to be figured out in terms of effective insulation made out of recycled materials but this study has figured out many key components of successful insulation.
Another study related to the transition of recycled materials, in this case wool, as insulation. Conducted by Rajesh D. Anandjiwala, Anton Botha, Sudhakar Muniyasamy, Mlando Mvubu, and Asis Patnaik, they highlight that 65-70% biodegradation was achieved for wool/RPET mats and the study showed that the alternative insulation materials were adequate in performance properties. Two types of waste wool fibers are used; Coring wool and Dorper wool (Anandjiwala,Botha,Muniyasamy, et.all.). They first tested and evaluated the isolated materials, and then combined the wool and RPET samples to test out its acoustic and thermal ability. This study reveals the relationship between moisture absorption and thermal conductivity. The natural fibers when tested, absorbed moisture when exposed to the environment, especially during high humidity conditions (Anandjiwala,Botha,Muniyasamy, et.all.). Their studies revealed that the mats had moisture resistance under high humidity conditions without changing the thermal insulation properties as seen in the image below. These positive results in analyzing recyclable materials as a form of effective insulation reveals to the audience the hopeful prospect of finding other recyclable materials to use as effective insulation.
In another similarly related case study, Roula Ghazal and Christian Ghiaus experiment with a desiccant wheel to identify thermal coefficients. A desiccant cooling unit uses passive energy based on evaporative cooling and absorption.The wheel is divided into two sections: desiccation and regeneration or in other words absorbed and desorbed. Their experimentations allowed them to carry out actual testing of a desiccant cooling system in comparison to mechanical cooling systems. Understanding the heat and mass transfer and its changes in an area. Instead of using a silica gel as a desiccant, maybe we can take their findings and use recyclable materials such as wool/clothing to contrast the thermal transfer, mass transfer and Nusselt number in comparison to silica gel testing.
In experiments by Jie Lin, Si-Min Huang, Ruzhu Wang, and Kian Jon Chua, they create a cross-flow membrane liquid desiccant dehumidifier and a counter-flow dew point evaporative cooler. Through these inventions they are trying to create a passive method for cooling the air. In regular systems in order to maintain a lowered humidity level, the machine has to cool the air temperature below its dew point, often overcooling and making the air temperature too cold to be comfortable (Huang et al.). They tested for many different outcomes, ultimately they found that they were able to control the humidity and air temperature to meet thermal comfort conditions (Huang et al.).