Effect of a solar-powered cooling system on growth and survival of Acheta domesticus in the Mekong Delta

Abstract

This study evaluated the effects of a solar-powered cooling system on the growth and survival of house crickets (Acheta domesticus) reared under tropical conditions in the Mekong Delta, Vietnam. A completely randomized design (CRD) was implemented with two treatments and five replicates per treatment. Treatment 1 (T1) served as the control with conventional enclosures lacking thermal regulation, while Treatment 2 (T2) employed insulated enclosures equipped with a solar-powered system integrating photovoltaic panels, temperature-humidity sensors (DHT22), fans, and ultrasonic misting devices. Each experimental unit consisted of 500 three-day-old nymphs raised in standardized composite rearing containers (60 × 40 × 40 cm) and fed with cornmeal, rice bran, and fresh vegetables. Environmental parameters, growth performance, and production indicators were monitored throughout the rearing cycle. The T2 group maintained an average internal temperature of 29,1±1,2°C and relative humidity of 60,7±4,3%, compared to 34,2±1,5°C and 45,2±5,0% in the T1 group. Crickets reared in the cooled environment exhibited significantly improved outcomes, including higher average body weight (1,47 ± 0,10 g vs. 1,24 ± 0,12 g), greater relative growth rate (142,5% vs. 118,3%), and faster time to marketable size (34,8 ± 1,8 vs. 40,2±2,5 days). Survival rate increased from 85,4% in T1 to 94,2% in T2, while feed conversion ratio improved from 2,8 to 2,2. Additionally, harvest yield rose from 445,1 g to 520,2 g per unit, and the proportion of marketable crickets increased by nearly 12%. These results highlight the biological and economic benefits of implementing solar-assisted microclimate control in small-scale insect farming. The system effectively stabilized thermal and humidity conditions using renewable energy, reducing heat stress and mortality while enhancing feed efficiency and growth performance. This approach offers a sustainable, low-cost solution for insect farming under hot and humid conditions and could be readily applied in rural or decentralized production systems. The integration of automated, sensor-based environmental control presents a scalable model for improving cricket production in tropical agriculture.