ORNL researchers develop promising geothermal energy storage system

The system has the potential to decrease electricity demand by up to 37%.

Researchers at the Oak Ridge National Laboratory have created a geothermal energy storage system that could lower peak electricity demand by up to 37% in homes while also assisting in the balancing of grid operations.

The system stores surplus energy from renewables.

The geothermal energy storage system is installed underground. It has been designed to store surplus electricity from solar energy and other renewable sources as thermal energy via a heat pump.

The system is made up of underground tanks that contain water and phase change materials. These materials can absorb and release energy during the transition between liquid and solid states.

The ORNL’s researchers design relies on low-cost materials and is installed at shallow depths to reduce drilling expenses. The energy that is stored can deliver hours of heating in the winter or hours of cooling in the summer. With this benefit, homeowners can avoid purchasing electricity at peak rates during hot and cold months.

Utilities can also benefit from the geothermal energy storage system.

It’s not only homeowners who will enjoy the cost-effective perks of this system. According to ORNL’s Xiaobing Liu, by shifting demand during peak times, this can also assist utilities in the better management of their loads. The end result is consumers save money and there is greater demand to use renewable energy and move further away from dirtier forms of energy.

The team at ORNL published results of the performance for their geothermal energy storage system from a simulation in the journal Applied Thermal Engineering. What’s more, used electric vehicle batteries are used to charge the network.

The US Department of Energy’s (DOE) largest science and energy laboratory, Oak Ridge National Laboratory focuses on carrying out basic and applied research to provide transformative solutions to help solve problems related to security and energy. ORNL researchers have placed a special focus on the study of clean energy, including technology for buildings, transportation and manufacturing and also explore the impacts of climate change.

Their geothermal energy storage system is among their latest clean energy projects.