ต้นทุนและผลตอบแทนในการติดตั้งระบบผลิตไฟฟ้าพลังงานแสงอาทิตย์ชนิดติดตั้งบนหลังคาของสำนักงานพลังงานจังหวัดแม่ฮ่องสอน

Abstract

This independent research has the objective is to study the costs and returns of installing a rooftop Solar Rooftop in Mae Hong Son Provincial Energy Office by analyzing data on average electrical energy use (kWh per year) and maximum electrical energy use (kWh per year) from the data on historical electricity use trends. To estimate the size of the electricity production capacity for installing a solar Rooftop system. Then design a solar Rooftop system by determining the size of the electricity production capacity and amount of electricity expected to be produced per year and selecting the appropriate solar Rooftop system. Then analyze basic information and the installation location of the solar Rooftop system by finding the right size and location for installing a solar Rooftop system and analyze data on electricity consumption that is suitable for choosing to install a solar Rooftop system for used in analyzing financial data by forecasting electricity demand from quantitative forecasts by using time series forecasting techniques with 2 methods 1) Simple Moving Average Method and 2) Decomposition Method and The Causal Forecasting Methods that is Simple Linear Regression Analysis to find the relationship between the demand for electricity consumption and other environmental factors. And then measure the forecast accuracy (Forecast Accuracy) using 3 methods: finding the average of absolute deviation (Mean Absolute Deviation or MAD), finding the mean square error (Mean Square Error or MSE) and finding the average percentage of absolute error (Mean Absolute Percentage Error or MAPE) by considering the value obtained to be the least value. In order for the forecast to be accurate. Then analyze financial data, including net present value (NPV) Payback period (PB) and Internal rate of return (IRR) and sensitivity analysis to assess feasibility value and return on investment of the project. The results of the study found that the size of the Solar Rooftop System covers electricity use the average power are 5 and 10 kilowatts maximum. The forecast value of electricity demand for a period of 25 years using the Simple Moving Average method is 165,014.08 units and has a total value of 843,799.52 baht, which is close to the size of a comprehensive Solar Rooftop System. Electricity use 5 kilowatts maximum Therefore, in analyzing financial data of the Solar Rooftop System that covers the average electricity use. Therefore, the analysis was chosen at a maximum size of 5 kilowatts maximum. The investment costs of the project are equal to 293,500 baht, in years 6 to 25, there is an annual maintenance fee for the solar energy production system of 15,000 baht and the discount rate is equal to 6.90% per year. The net present value (NPV) is equal to 128,217.74 baht. The payback period (PB) is equal to 8.97 years and the internal rate of return (IRR) is equal to 12.27% and from the sensitivity analysis of the project, all 3 approaches found that Approach, when the cost of installation is constant and the electricity cost increased by 10% with Net Present Value (NPV) of 181,861.26-baht, Payback Period (PB) of 7.89 years and Internal Rate of Return (IRR) of 14.31%. Approach 2: When installation costs increase 10% and fixed electricity bill has Net Present Value (NPV) of 98,867.34-baht, Payback Period (PB) of 9.86 years and Internal Rate of Return (IRR) of 10.70%. Approach 3: When installation costs increase by 10% and electricity costs increase 10% has Net Present Value (NPV) of 152,511.26 baht. Payback Period (PB) is 8.68 years, and the Internal Rate of Return (IRR) is 12.60%. The project is worth investing in 3 approaches and from the results of the said study, it was found that the investment project installs Solar Rooftop System with a maximum size of 5 kilowatts. It is worth the investment.