A Study Performance and Economic Optimization of A Combined Heating System of Air Source Heat Pump and Solar Hot Water

Abstract

The objective of the research is to study the efficiency of the combined air-source heat pump and solar hot water, moreover, to study the economic cost comparison of the system. The experiment is done by testing the system in Phetchaburi province. The results showed that the combined hot water system operated from 08:00 a.m. to 04:00 p.m. due to a solar intensity at this time made the solar hot water system to produce 60 degrees Celsius of hot water. Therefore, the overall coefficient of performance of the combined heating system varied in the ranges from 3.2 to 3.5. In the air source heat pump had an efficiency coefficient from 3.0 to 3.1 and the efficiency coefficient of solar thermal was range from 0.1 to 0.4. When comparing the economic cost of combined heating system and the coil system, the investment cost of the combined heating system is higher than electric heater. However, the electricity cost of the combined heating system is significantly lower than the electric heater. From this study, the combined heating system can be replaced the using of electric heater. The cost-effectiveness showed that the combined heating system earned 19 percent internal rate of return which was higher than the minimum retail rate of 12 percent. In addition, the combined heating system have long lifetime which can use last up to 15 years and payback in 4.8 years.