The Role of Green Technology in Sustainable Building
Green technology is an essential component of green building. It is responsible for reducing waste, pollution, and energy usage throughout a building’s lifetime. Different green technologies are incorporated during construction with the goal of being able to achieve sustainability, the property of meeting the needs of society without damaging or depleting natural resources (Yusof & Mydin, 2014). The use of green technologies also improves comfort, satisfaction, and indoor air quality while lowering expenses for equipment maintenance (Oberndorfer et al., 2007). Small ecosystems, solar energy systems, and green materials are examples of commonly used technologies in sustainable building.
A common strategy used in green building to reduce water, energy and maintenance costs is integrating ecosystems in the building’s design. Ecosystems can perform a multitude of tasks including rainwater storage, runoff reduction, and heating and cooling buildings (Kibert & Grosskopf, 2007). Green roofs, essentially roofs with vegetation, are commonly used in green building. Although green roofs are initially costlier than standard roofs, the amount of energy they save throughout their lifetime makes up for it. A simple green roof includes a roofing membrane, an insulation layer, a waterproofing membrane, a growing medium layer, and a vegetation layer as shown in Figure 1. Plants on the roof transpire water, cooling and transporting it back into the atmosphere. This process helps reduce the heat flux inside the building. As a result, the interior of the building is cooler than that of a building with a conventional roof. Additionally, green roofs are responsible for water management. The growing medium layer, which holds the plants’ roofs, is responsible for retaining storm water thereby reducing runoff. Reducing heavy runoff in urban areas decreases the amount of polluted rainwater that enters nearby bodies of water. Finally, green gardens serve as a habitat for insects. Beetles, ants, flies, spiders, and leafhoppers are a few of the creatures that have been spotted on currently functioning green roofs (Oberndorfer et al., 2007).
Figure 1: The Layers of a Simple Green Roof, Source: Matthews, R. (2012, July 30). Types of Green Roofs. Retrieved from http://www.thegreenmarketoracle.com/
The use of solar energy is another very popular technique used in green building. Radiant light and heat from the sun are converted into electrical energy and then used for various functions. Examples of solar technologies include solar heating, solar photovoltaic, solar thermal electricity and solar architecture. Solar technologies are beneficial because they do not pollute the environment, require minimal maintenance, and have a lifespan of 20 years. Solar energy systems can be characterized as either active and passive. Active solar energy uses mechanical devices to store and distribute solar energy throughout a building. An example of active solar heating is a method that involves collecting, storing, and distributing heat through the use of pumps, fans, and blowers. Another method involves heating water with the sun and then using the water as a medium to transfer heat throughout the system (Yusof & Mydin, 2014). Companies are currently finding new ways to utilize solar energy. Alcoa, an aluminum manufacturing company, recently came up with the innovative idea of self-cleaning panels. In their design, architectural panels use sunlight to decompose organic pollutants that build up on their surface into nontoxic matter that is easily washed away by rain (Frost & Sullivan, 2011). This technology is able to massively cut maintenance costs. Passive solar energy, on the other hand, refers to the usage of the sun’s energy without the involvement of any mechanical equipment. The placement of a building so that the majority of its windows face south is a passive solar energy technique that provides maximum natural lighting and heat. Figure 2 illustrates how solar windows work during the summer and winter seasons. In addition, thermal mass, a solid or liquid material that absorbs and stores warmth and coolness, is placed to absorb solar energy entering through windows. Thermal mass includes bricks, stone, concrete, and water (Yusof & Mydin, 2014).
Figure 2: Solar Windows During the Summer (left) and Winter (right), Source: U.S. Department of Energy. (n.d.). Dynamic window coatings to reduce building energy demand. Retrieved from http://carboncycle2.lbl.gov/
In addition to green technologies, sustainable building incorporates green materials. Forty percent of all raw materials used globally, equal to three billion tons, are utilized for building and construction activities every year. Green building materials can help reduce negative environmental effects that result from the fabrication, processing, transportation, installation, and disposal of construction materials. To minimize the consumption of raw materials in construction, a set of guidelines is followed. Desired materials for green construction are resource efficient, energy efficient, water efficient, affordable, and beneficial to the indoor air quality. To avoid using raw materials, engineers choose those which are common, locally available, recycled, alternatives to natural wood, and durable whenever possible. Furthermore, engineers achieve energy efficiency and water conservation by utilizing materials, components, and systems that help reduce the consumption of these natural resources in buildings. Additionally, the use of materials that are nontoxic, moisture resistant and have minimal chemical emissions will improve indoor air quality (Mehta G., Mehta A. and Sharma, 2014). Being environment-friendly and financially beneficial has increased green technology’s popularity during these past few decades.
References
Frost & Sullivan. (2011, June). Advances in green building technology. Advanced Coatings & Surface Technology, 24(6), 6+. Retrieved from http://go.galegroup.com/
Kibert, C., & Grosskopf, K. (2007). ENVISIONING NEXT-GENERATION GREEN BUILDINGS. Journal of Land Use & Environmental Law, 23(1), 145-160. Retrieved from http://www.jstor.org/stable/42842944
Mehta G., Mehta A., & Sharma, B. (2014). Selection of Materials for Green Construction: A Review. IOSR Journal of Mechanical and Civil Engineering, 11(6), 80-83.
Oberndorfer, E., Lundholm, J., Bass, B., Coffman, R. R., Doshi, H., Dunnett, N., Gaffin, S., Kohler, M., Liu, K., & Rowe, B. (2007). Green roofs as urban ecosystems: ecological structures, functions, and services. BioScience, 57(10), 823-833.
Yusof, S. H., & Mydin, M. A. O. (2014). SOLAR INTEGRATED ENERGY SYSTEM FOR GREEN BUILDING. Acta Technica Corviniensis-Bulletin of Engineering, 7(3), 115.
