農電共生是現在常見的太陽能設置型態，既能保有農作糧食，也可以發展太陽能綠電，最近美國研究指出，與傳統的太陽能板相比，農電共生的太陽能系統架設高度較高，能提高模組散熱冷卻效果，帶來較佳的發電表現、還能延長模組壽命。

美國康乃爾大學團隊這次以物理學角度來研究，從提高太陽能板功率轉換效率跟延長模組壽命來看農電共生的成本跟收益。根據指導教授 Max Zhang 先前的研究，美國約有 40% 公用事業太陽能電廠建立在農地上，而大約 84% 被認為適合發展太陽能的土地為農用地。

為了不與農爭地，出現綠電與農業相互扞格的尷尬場面，農電共生為一個選項。團隊利用基於流體力學的微氣候模型和太陽能板溫度資料，評估農電共生太陽能板的高度、地面光反射和蒸散速率，最終團隊認為，農電共生可以解決未來的糧食──能源問題（food-energy problems）。

結果顯示，比起在一般地面上架設太陽能板，在植披上的模組表面溫度下降更快，研究指出，對比在地面上 50 公分高的太陽能板，在大豆上方 4 公尺處的太陽能板降溫可達 10 度。

這是因為植被和土壤的蒸發速率和地表反射率強，導致模組的降溫效果更顯著，這種被動冷卻不僅能提高太陽能板的發電效率，也能延長太陽能板使用壽命，最終提高長期經濟潛力，第一作者 Henry Williams 表示，研究顯示出雙重利益，一方面可以生產糧食，另一方面也提高太陽能的經濟效益。

雖然說更高的太陽能板，意味著更高的初期成本，但根據世界資源研究所的資料，到 2050 年，為了養活  100 億人，全球糧食需求預計將增長 50%，農電共生則是一種互惠互利的概念。

• Made in the shade: Growing crops at solar farms yields efficiency

（首圖來源：Unsplash）

Agro-photovoltaics (Agro-PV) is a common solar installation that combines farming with solar energy production. It not only maintains agricultural production but also promotes green electricity production. Recently, a study in the United States has shown that Agro-PV systems have a higher mounting height than traditional solar panels, which can improve module cooling and bring better power generation performance while also extending module lifespan.

This time, a team from Cornell University used a physics perspective to study the cost and benefits of Agro-PV, focusing on improving solar panel power conversion efficiency and extending module lifespan. According to Professor Max Zhang’s previous research, about 40% of utility-scale solar power plants in the United States are built on farmland, and approximately 84% of land suitable for solar energy development is considered agricultural land.

o avoid land conflicts with farming, the Agro-PV is an option that can mutually benefit both electricity production and farming. The team used a microclimate model based on fluid mechanics and temperature data from solar panels to evaluate the height of Agro-PV solar panels, ground light reflection, and transpiration rate. The team ultimately believed that Agro-PV could solve future food-energy problems.

The results showed that compared to mounting solar panels on the ground, the module surface temperature on crops drops faster. The study showed that compared to solar panels mounted 50 cm above the ground, solar panels located 4 meters above soybeans can cool down by 10 degrees. This is because vegetation and soil have a higher transpiration rate and ground reflectivity, resulting in a more significant cooling effect on modules. This passive cooling not only improves solar panel power generation efficiency but also extends the module’s lifespan, ultimately improving the long-term economic potential. First author Henry Williams stated that the study shows dual benefits, both in terms of food production and solar energy economic benefits.

Although higher solar panels mean higher initial costs, according to data from the World Resources Institute, global food demand is expected to increase by 50% by 2050 to feed the world’s 10 billion people. Therefore, Agro-PV is a mutually beneficial concept.

Image Source: Unsplash

Source: TechNews Taiwan https://technews.tw/2023/03/06/growing-crops-solar-farms/