Evaluating the efficiency of energy use in cultivation of medicinal plants: a case study on garden thyme and peppermint employing life cycle assessment and support vector machine modeling

This study utilized two questionnaires to assess energy consumption in farms and the energy yield from garden thyme and peppermint over multiple years. During face-to-face meetings with farmers, 55 questionnaires were completed. The Ecoinvent database was utilized to gather necessary information, and Simapro software was employed for LCA calculations. Additionally, the study utilized the SVM model to predict the energy output of garden thyme and peppermint. The findings revealed that electricity accounted for the highest energy consumption in thyme cultivation, representing 41% for garden thyme and 36% for peppermint of the total energy usage. Urea fertilizer played a significant role in energy consumption for both peppermint and garden thyme agriculture, comprising 34% of the total energy usage after electricity. Furthermore, the energy production to consumption ratio for five years of garden thyme and peppermint cultivation stood at approximately 2.2 and 2.17, respectively. The results demonstrated that the SVM model exhibited high accuracy and low error rates in estimating energy output for garden thyme and peppermint. The evaluation criteria for actual versus predicted data yielded an R2 value of 0.9796 and RMSE of 0.0367 for garden thyme, and an R2 value of 0.9765 and RMSE of 0.0081 for peppermint. These metrics indicate a strong performance in estimating output energy for both plants.