Feasibility study of an off-grid hybrid energy system with zero emissions to meet all energy demands of a household in Turkey

Due to the emission of greenhouse gases into the atmosphere resulting from the use of fossil fuels in electricity generation, environmental damages are incurred, contributing to global warming. Additionally, the depletion of fossil fuels as finite resources indicates that they are not a sustainable solution for meeting energy needs. Consequently, many countries are increasingly shifting towards renewable energy systems (RES). The significance attributed to RES in Turkey is on the rise, aligning with its commitment under the Paris Climate Agreement to reduce greenhouse gas emissions. Another motivation for Turkey's focus on RES is to mitigate dependency on external sources for electricity. Beyond the energy sector, another sector characterized by excessive fossil fuel usage is transportation and in recent years, electric vehicles have been favored over traditional modes of transportation. All these reasons highlight the growing importance of emissions-free RES and environmentally friendly electric vehicles. RES utilize renewable energy sources such as solar and wind energy. However, these sources have the disadvantage of being intermittent by nature. To overcome this challenge, hybrid energy systems incorporating multiple RES and storage units are employed. This study utilizes the HOMER program to investigate the technical and economic feasibility of meeting the electricity and thermal load demands of a four-person household residing in a detached house in the Yalova province of the Marmara Region with a zero-emission Hybrid Energy System (HES). Wind and solar energy are chosen as energy sources. Initially, the study is conducted for a scenario considering only electrical loads. The electricity load includes the household's electrical consumption and the energy required to charge an assumed electric vehicle used by the family. Two different scenarios of daily and weekly charging for the electric vehicle are examined, concluding that daily charging is more cost-effective. The net present cost of the proposed most cost-effective system for this scenario is found to be $29,813. Subsequently, considering thermal load demands, the study is repeated with three scenarios addressing thermal load demand in different ways. The results are compared and analyzed. The study concludes that while the electricity load demands can be met with zero-emission systems, meeting thermal load with a zero-emission HES is not technically and economically feasible. Additionally, solar system analysis is conducted for the proposed most-effective system using Sketchup, Skelion and PVGIS. The study is repeated for a selected province from each geographical region in Turkey, focusing on scenarios considering only electrical loads, and the results are compared and analyzed. The study identifies that İzmir has the lowest net present cost at $22,378, while Yalova records the highest net present cost value. Keywords: Renewable energy, Electric vehicles, Hybrid energy systems, Zero emissions, Sustainable energy