Carbon Dioxide Absorption by Green Walls : An Investigation of Plants on Facades

The pressure on current urban ecosystems is an ongoing problem as greenhouse gaseshave a negative impact on the climate but also on people around the world. As manycities are densely populated, it becomes difficult to introduce more greenery into citieswithout taking up a lot of space, for example by building parks. Therefore, vertical plantsystems placed on facades around the city can be a solution to mitigate the effects ofurban warming and help absorb carbon emissions. The aim of the study is to expandthe knowledge of plant façades with respect to carbon dioxide absorption. The studyexamines three key aspects, namely the economics of installation and maintenance, thelong-term sustainability of carbon absorption and the energy-saving potential of greenwall insulation.The different data collection methods used are literature studies and interviews withcontractors. Fytotextile on the modules was the material whose U-value was used forthe energy calculations; these are used by a company in Spain, Terapia Urbana. Theirquotes were also used for financial calculations to see the viability from an economicperspective.The study shows that the most suitable option for using plants on façades is to chooseresistant and fast-growing perennial plants that require little maintenance as these arethe most optimal for use on façades. The plant Flock Fist was recognized as a suitablespecies for implementation on green walls through various surveys and in-depthinterviews, due to its extended lifespan and inherent ease of maintenance. Analysesinvolving economic, energy and sustainability calculations show that the incorporationof green walls is economically unprofitable. However, in terms of sustainability andenergy efficiency, it appears to be a more practical and beneficial solution.The results show that installing plant façades on buildings can reduce energyconsumption and promote sustainability. The results also revealed that a building with400sqm of green façade can absorb the annual CO2 emissions of a building for 25 years.BIM 3 Requirements and Verification - Design projects are compared with this study'scalculation to check the energy consumption. Plant facades can help buildings achievehigher levels in Miljöbyggnad because of the extra insulation. The study concludes that1100 SEK is saved every year with a plant facade due to the reduction of energyconsumption. The results also highlighted that a building with 400sqm of green façadecan absorb the yearly CO2 emissions of a building for 25 years. Plant facades can helpbuildings achieve higher levels in Miljöbyggnad as the extra insulation helps to reduceenergy consumption. The study also shows that the value of buildings with greenfaçades increases by several percentage points each year.The care and maintenance of the plants were important factors for their survival.However, economic factors were limited due to high installation costs and small savingsrelative to the investment. Plant walls can absorb a significant amount of carbondioxide, but the lack of research on their exact capacity was a challenge.Keywords: Carbon dioxide, White Ness, Fytotextile, Green facades, Plant walls