本論文成功地研究熱電晶片利用熱/冷水發電的機制，實驗得知冷/熱面的 溫差越大，則熱電晶片轉換的電能越大。對於單一熱電晶片其轉換的電能分 別為4.8W、3.4W、2.8W分別對於冷面冷水溫度為1oC；10oC；和25 oC。經由 對單一晶片的實驗量測，發現最大的發電效率與冷熱面溫差有關且為二次方 函數。由實物上得知:熱電晶片的熱面的熱源溫度容易獲得，但其冷面的散熱 卻難，由本研究得知不論是其自身的散熱或加上散熱鰭片，其散熱效果都不 佳(溫差在20度以內)。因此，本文提出冷面的散熱為水冷式(環境的溫度約 28~30oC)，進而對六片晶片模組作熱電轉換測試。實驗結果發現：當加熱溫 度由60增加到90oC，電壓可以由5.8V增加到11.1V；電流則由0.31A增加至 0.53A；而電能則由1.8W增加到5.9W。
5.2 未來發展
未來，將研發設計一熱電(thermal-electric generation, TEG)系統(圖 5-1)，
此系統包含一50 個串聯熱致電晶片模組、熱導管、以及電力系統。其原理乃 是利用太陽能熱水器(圖 5-2)集熱板加熱冷水，被加熱的熱水將被輸送至儲熱 水槽儲存。此一儲熱槽之穩定熱源利用熱導管將熱引出，經由此熱導管將熱 水傳遞至熱電晶片的熱面端，而熱電晶片之冷端面則連接一冷水導管與散熱 鰭片，用以將冷端面之上升熱傳走，以造成上下基板有一較大之溫度差。 TEG 系統利用此溫差將會產生電力，而此產生的電力將利用 DC/AC 轉換器 ( inverter)傳至家庭電器利用，或利用 UPS 不斷電系統儲存(如圖 5-3)。
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圖5-1 熱電模組(50片TEG)
圖5.2 太陽能熱水器
圖5-3、熱電發電系統架構流程圖
熱電發電模組 電力調節系統
TEG晶片
太陽熱水器 UPS 系統
小型電器設備
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