日光調控太陽能免追日系統應用於植物工廠之直漫射光模擬分析

近年氣候變遷越發嚴重，環保及綠色能源的重要性也越來越高。而許多農業在農地建置太陽能板時，造成棚下日照不足而影響作物生長，影響了農地農用，植物選擇也因此受限。但也有些人卻需要遮擋多餘日照以防不同種植物受到過多曝曬。　　為了解決這些問題，本實驗室研究設計一光學系統結構應用在植物工廠上，將原本平鋪且直接面對太陽之太陽能板改為垂直擺放而不朝向太陽，取而代之的是線型菲涅爾透鏡做為單格屋頂結構之天窗來改變太陽的直射光光路。　　光線經由菲涅爾天窗聚焦後，會經由底下所設計之反射板再打到垂直擺放的太陽能板上，並且根據不同的季節與氣候狀況來做調控以達到植物工廠的需求。而其中會將太陽的直射光與漫射光分開進行討論，以讓模擬能夠更為貼近最真實的情況。　　利用此概念初步設計之溫室，訂定至少要有總能量的20%供植物照明為目標，而其餘的光能就用於太陽能光伏發電，目前也建置了一個50平方公尺的實驗場域來做展示並以利未來驗證工作。

關鍵字

日光調控；太陽能；免追日系統；植物工廠；光學模擬

並列摘要

Several agriculture fields installed with solar panels will lack for the sunshine which affects the growth of crops below those panels, and then have very limited choice of plants. However, some others need installation of shielding to avoid too much illumination on the plants. 　In order to solve these problems, an optical system structure was designed for the plant factory. the solar panels are erected to be vertical to the ground rather then facing to the sun. Instead, the roof surface becomes a grid pattern of linear Fresnel lens to focus and deflect direct sunlight. 　Together with well designed reflectors underneath the Fresnel lens, the direct sunlight can be redirected toward solar panels which have been vertically installed. Each cell structure will be controlled individually to adapt weather or seasonal change of sunlight condition to make the overall illumination in the plant factory meeting the requirement all the times. Among them, the direct light and diffuse light will be discussed separately to make the simulation close to the most realistic situation. The concept is implemented with a greenhouse designed on the target of providing 20% of solar energy for plant illumination, and the rest of the solar energy is directed for photovoltaic generation. A 50m2 prototype has also been built for demonstration.