/technologies/power-management/b/blog/posts/sage-geothermal-built-an-underground-energy-storage-system-for-renewablesThe system produced energy to power fans. (Image Credit: Sage Geosystems) Renewable energy is now more affordable to generate and use compared to energy produced from oil and gas. However, solar and wind are more problematic due to storage. Sage Ge.en-USTelligent Community 12