A basic solar thermal or PV-assisted heating setup for a modest home may run $8,000-$15,000, while larger, high-efficiency configurations with storage and full integration can reach $15,000-$25,000+. Per-unit costs vary: collectors can be $20-$150 per square foot installed for solar thermal or. How much does a solar thermal storage system cost? 1. THE COST OF A SOLAR THERMAL STORAGE SYSTEM CAN VARY SIGNIFICANTLY. Major factors influencing expenditure include 1. the type of system employed, 2. installation logistics and labor costs, 4. Sand stores approximately 19 kWh/m³ at 80°C operating temperature, rising to 37 kWh/m³ at 150°C and 75 kWh/m³ at 300°C. These. Solstice turns renewable energy into high-temperature thermal storage that can power your industrial processes 24/7. Additionally, installation expenses may add from $700 to $1500 to the total, leading to a comprehensive expenditure of about $1700 to $4500.