Environmental impact assessment using ecological footprint method: Case study Energy Engineering Department of Sharif University of Technology

Ecological footprint is an index to quantify the environmental impacts of man’s life. In this research, the ecological footprint index is used to assess the environmental effects of the activities of Energy Engineering Department of Sharif University of Technology. For this purpose, the required data such as energy and water consumption and the produced wasted of the faculty are collected. In addition, to compute the indirect energy consumption caused by the transportation of the students, a questionnaire survey is performed and its results are used to estimate the annual consumption of the energy in all modes of the transportation. Finally, using the standard method, the ecological footprint index is calculated for the activities of the faculty. The results indicate that the ecological footprint of the faculty is equivalent to the 41456.37 global hectares per year that its major part is related to gas and electricity consumption of the faculty. Therefore, the reduction of energy consumption in the building will have a significant impact on the reduction of this index. Furthermore, the increase of the waste recycling as well as increase of public transportation usage are other ways for reducing this index to reach sustainability in the building. The effect of each of these solutions on the reduction of ecological footprint of the faculty is thoroughly analyzed.
In this study, to illustrate the environmental impacts of household, commercial, and public sectors in Iran, the activities of the Energy Engineering Department of Sharif University of Technology is studied as a case study. Previously, Soleimani and Avami (2016) assessed the activity of this building using life cycle analysis method. In order to reduce emissions of carbon dioxide, low-cost methods such as efficient shadings were proposed. In this study, the activity of the faculty is studied using ecological footprint method. In addition to direct effects, the indirect effects of the faculty activities are considered as much as possible in the present study using ecological footprint index to determine the sustainability of the building.
Methodology
Given the complexity of the ecological footprint method, this study only refers to the operation of the building and the stages of construction and destruction are not included. The faculty environmental effects include direct and indirect effects. The direct effects are the results of energy and material consumption or waste production at the faculty site. The indirect effects are the results of the consumption of materials or energy in a place rather than the faculty site. In this study, transportation of students to the faculty conducted by various modes of transportation is among the indirect effects. In this study, the consumption of electricity and gas are calculated using electricity and gas bills for one year. Using emission factors, carbon dioxide emitted by fossil fuel consumption is calculated. The land area required to absorb this amount of carbon dioxide is calculated and finally using the equilibrium factor, the land is converted to global hectares. The water consumption is also calculated using water bills for one year. Forest land is considered as the source of water production and annual consumption of water is converted to the forest land. Finally, the equilibrium coefficient converted it into global hectares. Concerning the fuel consumption related to the required transportation for the students, a questionnaire survey was performed among them in the faculty. In this way, the number of students from any mode of transportation and kilometers traveled by each mode of transportation are calculated. Using the results of this survey, per capita fuel consumption calculated for each mode of transportation as well as the annual fuel consumption of each mode is calculated and converted to global hectares similar to energy consumption of the building. At the end, the total ecological footprint of the faculty is obtained by the sum of values.
Discussion of Results
Table 1 shows the summary of results.
Table 1: summary of the results of ecological footprint of the activities of the department
Energy consumption of faculty Waste production
Infrastructure land Energy consumption of transportation
natural gas electricity Water Plastic Paper Riding BRT Subway
Ecological footprint (gha /year) 87.24310 3.15593 97.5 5737.0 574.0 377.1 147.1512 7.7 86.23

According to the results, most of the ecological footprint is caused by the consumption of energy at the department. In order to assess the potential of reducing the ecological footprint, the ecological footprint of electricity and gas consumption of the faculty is calculated assuming global average values for electricity and gas consumption per capita in two different scenarios. In scenario 1, the gas consumption of the building is reduced and assumed the same as the global gas consumption per capita. This value is added to the current electricity consumption of the faculty. In scenario 2 electricity consumption is calculated by assuming the global electricity consumption per capita and its value is added to the current gas consumption of the faculty. According to the results, the ecological footprint caused by the energy consumption of the faculty in scenarios 1 and 2 will reduce 14.3% and 20.7% respectively.
The major part of the waste products is the paper and the plastic. The recycling rate of the plastic and the paper in Iran are estimated as 9% and 2%, respectively. While these values for Europe were estimated as 69.2% and 71.7% in 2014, respectively. The increase of recycling rate for the plastic and the paper will reduce the ecological footprint of wastes. The major part of the ecological footprint of the transportation is related to private cars. The use of public transportation by students significantly reduces the ecological footprint of transportation. Replacing the private cars with the subway and the BRT reduce the ecological footprint of the transportation 93.4% and 77.8%, respectively.
Conclusion
In this study, the environmental impact caused by the activities of Energy Engineering Department of Sharif University of Technology, was studied using the ecological footprint method. The results indicate that the total ecological footprint of the faculty is 41456.37 hectares per year that its major part is related to gas and electricity consumption of the faculty. Thus, the reduction of energy consumption of the building will reduce this index significantly. Moreover, increasing the recycling rate of the wastes and using public transportation are the other solutions of reducing this index to reach sustainability.