Tucson Electric Power receives approval to develop innovative energy storage facilities

Tucson Electric Power (TEP) will enter into long-term agreements with E.ON Climate & Renewables and NextEra Energy Resources for the construction of two large, innovative energy storage systems.

The projects, approved by the Arizona Corporation Commission (ACC), will be used to improve service reliability and study how such systems can support the expansion of solar power resources and other renewable energy technologies.

In June 2015, TEP issued a request for proposals to lease a large, 10 megawatt (MW) energy storage system. With bids submitted by more than 20 qualified vendors, TEP was able to select two competitively-priced proposals.

Both projects will be developed under 10-year contracts with performance agreements to protect customers and the company from financial risks associated with investing in new technologies.

The projects include:

• A 10-MW lithium nickel-manganese-cobalt (NMC) facility at a TEP substation near Interstate 10 and West Grant Road. The system will be built by NextEra Energy Resources, based in Juno Beach, Fla., and is expected to be in operation late this year.
• A 10-MW lithium titanate oxide (LTO) storage facility and accompanying 2-MW solar array located at the University of Arizona Science and Technology Park southeast of Tucson. The facility will be built by Chicago-based E.ON Climate & Renewables and is expected to be completed in the first quarter of 2017.

The systems will be used primarily to help maintain the required balance between energy demand and supply. Energy storage systems can boost power output levels more quickly than conventional generating resources. 

Carmine Tilghman, a TEP Senior Director, said:

"Because our project partners were motivated to demonstrate the capabilities of their respective technologies, they submitted favorable bids that will allow us to build both projects for less than our original estimated cost to build a single 10 MW system. These systems will help us build a more resilient grid at a reduced cost to consumers."