Part 3: Other Innovative Storage Technologies

Part 1 of this examination of the Texas energy storage market reviewed utility-scale applications in the state, while Part 2 highlighted several of the smaller-scale microgrid and community applications. This post discusses the other innovative storage technologies being used throughout the state.

Compressed Air Energy Storage Projects

The single operational compressed air energy storage project (2 MW) is located in Seminole, Texas and known as Texas Dispatachable Wind 1, LLC (TDW). The TDW project consists of a 3 MW wind turbine, a General Compression Advanced Energy Storage (GCAES™) system, a geological salt storage cavern, and other electrical and ancillary facilities. The project was supported by a grant from the Texas Commission on Environmental Quality. These compressed air energy storage systems are responsive enough to provide spinning reserves, voltage support, and frequency regulation.

Once constructed, the Apex Bethel Energy Center compressed air energy storage (CAES) project is rated at 317 MW of capacity and will be the largest storage project in the Texas market. The project, located at Tennessee Colony in Anderson County, Texas, has all of the regulatory approvals needed to put the project in place. An Interconnection Agreement has also been entered. It is currently scheduled to begin construction in June 2017 and become operational in 2020. The project is planned to provide black start, frequency regulation, ramping, and renewables energy time shift. The project uses a salt dome formation that is perhaps the only available existing underground structure of its size in Texas suitable for a CAES resource.

A new company, Chamisa Energy, has announced a compressed-air energy storage (CAES) unit to pair with wind power in Swisher County, Texas. The project will compress air into salt caverns that will be carved 2,000 feet below the surface. Chamisa has partnered with Dresser-Rand and intends to use their SMARTCAES technology, which provides a wide array of electrical services including peaking, intermediate, base load, tolling and ancillary services. The aim is to facilitate the accommodation of intermittent power resources to the grid by providing storage and other grid reliability services in the wind-region of the Texas Panhandle. The project will likely connect to the ERCOT CREZ lines that are crossing Swisher County, and to Xcel’s system in the Southwest Power Pool (SPP). This would put Chamisa in the interesting position of being able to arbitrage price differences between the two power markets. The generation capacity could be expanded to 810 megawatts in phases by creating more caverns. The project is in a full study stage at ERCOT as of the August 2016 (see GIS Report linked above). The 270 MW facility is expected to come online in 2018.

Thermal Projects

The state’s 13 operational thermal projects totaling 111,452 kW of capacity include chilled water thermal and ice thermal technologies. These projects are all operated on behalf of end-user companies and public institutions that serve to shift load and/or reduce peak load demand charges, providing significant benefits to the over-all performance of the grid.

The largest thermal project is a 90,000 kW chilled water unit owned and operated by Brazos Electric Coop in Jacksboro, Texas. Chilled water thermal technology improves the technical and economic performance of gas turbines by providing cooling off the air flow entering the generator. Water is chilled at off-peak times and stored in a thermal energy storage tank, and the following day is pulled from the tank during peak times to chill the inlet air of the gas turbine, resulting in increased output.

The second largest thermal project is a J.C. Penney Company, Inc. 4,425 kW unit in Plano, Texas. Their system offsets the peak demands of electrical use by making ice each night to cool the building the following day.

Flywheel Projects

There are three flywheel projects in Texas totaling 5,615 kW, including a 4,800 kW unit in Austin used to protect Austin Energy’s new control center by increasing power backup reliability. In addition, the Texas Scottish Rite Hospital for Children in Dallas and JV Industrial Data Center in La Porte use flywheels to improve resiliency by providing electric spinning supply reserve capacity.

Part 4 of this series will discuss the lessons Texas’ storage projects can offer for increased utilization of electric energy storage in the United States.