Feasibility Study of Using Renewable Energies in the Water and Wastewater Industry (Case Study: Tehran Water and Wastewater Company)

Climate change refers to any significant and long-term alterations in global or regional weather conditions. The impact of climate change on the industrial plans is enormous, while the water supply sector has been challenged to examine how it could continuously operate in the current situation. Optimization of energy consumption and reduction of Greenhouse Gases (GHG) emissions are some of the priorities of water companies. The objective of the study is to propose a novel evaluation approach to the feasibility of using renewable energies (solar, wind, and biomass) in the water and wastewater industry. Tehran Water and Wastewater Company consists of six regional districts and forecasting of its energy consumption, power costs, and carbon tax rates for the next ten years was done by using the regression model. The results indicated that increase in water supply and electricity consumption was evidenced by the increase in Tehran's annual population. GHG emissions were calculated in two scenarios, the first of which is based on the total supply of required electricity from conventional power plants and the second is on the generation of approximately one-third by renewable energies. In addition to the higher emissions of carbon dioxide (CO2) from diesel and oil power plants than the natural gas-fueled plants, by increasing the carbon tax to more than 30 USD per tonne of CO2, it is expected that the emissions will be reduced by 30 % in all fossil-fueled power plant types. Results showed that a small amount of tax was not effective in reducing GHG emissions.