Scheduled to be completed in 2015, the two projects will each have the capacity to store 7.8 megawatt-hours (MWh) of energy.
The first project, Elwood Energy Storage Center, will be situated on Pilsen Road in West Chicago, while the second project, Jake Energy Storage Center, will be located on Brandon Road in Joliet.
BYD America will supply the lithium iron phosphate battery storage modules for the two projects.
RES Americas will develop and provide the energy storage control and dispatch systems for the each center, which is expected to be operated for about 10 years.
RES Americas acquired the projects that were in development phase from Glidepath Power in September 2014.
Interconnected to the local Commonwealth Edison (ComEd) electric grid, the projects will provide real-time frequency regulation service to the PJM ancillary services market.
RES Americas vice president for energy storage Victor Babbitt said: "The Jake and Elwood Energy Storage Centers represent commercial installations of cutting-edge energy storage technology.
"These projects will increase the reliability and quality of ComEd’s grid in these communities which, in turn, may help attract new business that demands a high-quality & reliable electricity supply."
