- 學位論文
再生能源(太陽能與風力)應用在冷凍與熱泵之研究
The Application Research of Using Renewable Energy Source (Solar Energy and Wind Force) in Refrigeration and Heat Pump
摘要
本研究的目標是研發太陽電池驅動吸收式冰箱、太陽能熱電晶片冷水器及風力熱泵，具體工作包括：於緊急情況使用，可以被太陽能驅動在沒有電網的地方，在夜晚或雨天時，它可以被電池驅動。電池可以電網的電驅動及充飽後做為備用供給能源。實驗探討由太陽電池驅動熱電晶片冷水器的冷卻性能，並比較固定直流電驅動時的實驗結果。太陽能是乾淨的和無限的，可以由太陽能電池收集。我們使用太陽電池驅動熱電晶片冷水器，其中冷側連接冷水槽。提出一個由風力直接驅動熱泵系統可以減少由風能轉為電能，電能再轉為動力能的能量損失。熱泵和冰水機的轉換是由一個四通閥控制來轉換。 根據太陽能吸收式冰箱實驗結果，提出之系統在太陽輻照度在550 to 700w/m2，500ml常溫的水為負載下。經過160分鐘，此冷凍系統維持溫度在攝氏5到8度之間，氨-水吸收式冰箱的COP值大約為0.25。在太陽能熱電晶片冷水器結果可以發現250 ml的水可以由18.5℃冷卻13℃，其中COP是0.55到1.05之間變化，在太陽輻射變化在450 W/m^2到1000 W/m^2之間的情況下。在太陽能熱電熱水器性能實驗結果可以發現250 ml的水可以由18.5℃冷卻13℃，其中COP是0.55到1.05之間變化，在太陽輻射變化在450 W/m^2到1000 W/m^2之間。本風力直接驅動熱泵實驗的結果顯示，在室外溫度為35 ºC，室內溫度為25 ºC，產生冷水的效率為54.38%；在室外及室內溫度都是10 ºC的情況下，產生熱水的效率為52.25%。 因此，太陽能電池吸收式冰箱可已被預期使用在偏遠低區的冷凍食物及飲料；太陽能電池驅動熱電晶片冷水器是可行和有效的；由風能直接驅動熱泵可以提升風能間接驅動熱泵的轉換效率。
並列摘要
The goal of this dissertation is to experimentally investigate the solar absorption refrigerator, the solar thermoelectric cooler, and the wind directly forced heat pump. The specific tasks of this study include the following issues. In emergency situations, the systems can be powered by solar energy when the grid power is lacked. In the evenings or rainy days, the systems can be powered by storage battery. The storage battery can be powered by the grid power supply when the supply is available and the battery can be full charged as a backup supply. This study conduct experimental explorations on cooling performance of the thermoelectric cooler being driven by solar cells, as well as comparison results to the performance being driven by fixed direct current. Solar energy is clear and limitless, and can be collected by solar cells. We use solar cells to drive thermoelectric cooler, where the cold side is connected to the water tank. This study proposes a new technique to directly adopt the wind force to drive heat pump systems, which can effectively reduce the energy conversion losses during the processes of wind force energy converting to electric energy and electric energy converting to kinetic energy. The operation of heat pump system transfers between the chiller and heat that is controlled by a four-way valve. In solar absorption refrigerator performance test, the alternation of solar irradiance 550 to 700w/m2 is adopted as solar energy source and 500ml of ambient temperature water is adopted as the cooling load. After 160 minutes, the proposed refrigerator can maintain the temperate at 5 to 8℃, the coefficient of performance (COP) of NH3-H2O absorption refrigerator system is about 0.25. In solar thermoelectric performance test, it is found that 250 ml water can be cooled from 18.5℃ to 13℃, where the corresponding coefficient of performance (COP) is change between 0.55 and 1.05, when the solar insolation is ranged between 450 W/m^2 and 1000 W/m^2. In wind directly forced heat pump performance test, the experimental results indicated that the average value for cool water producing efficiency of 54.38% in the outdoor temperature is 35ºC and the indoor temperature is 25ºC and the hot water producing efficiency of 52.25% in the outdoor temperature and the indoor temperature both are 10ºC. From our experimental results, an absorption refrigerator driven by solar cell can be expected to be used in remote areas or for refrigeration of food and beverages in outdoor environments or activities. The thermoelectric cooler driven by solar cell is feasible and effective for energy saving issues. Heat pump directly driven by wind energy can improve the efficiency of heat pump indirectly driven by wind energy.