July 9, 2020: Tucson Electric Power, the Arizona, US utility, said on June 26 it aimed to provide more than 70% of its power from wind and solar sources, to be supported with 1.4GW of energy storage including battery systems.
The utility is one of a growing line of power companies in the US that appear to be taking battery storage on board as part of their energy portfolios, with national capacity growing from around 500MW in 2015 to a projected 2,500MW by 2023, according to the US Energy Information Administration.
TEP filed an Integrated Resource Plan with the Arizona Corporation Commission on June 26, which outlined a 15-year plan for an energy portfolio, proposing to close the remaining coal-fired plants within 12 years.
The first step is a new 100MW/30MWh solar-plus-storage facility south of Tucson within a year.
“The Preferred Portfolio assumes the implementation of 1.4GW of new BESS by 2035 (in addition to the 50MW that is in-service or under contract today), representing 84% of the grid-balancing resources in TEP’s portfolio,” says the IRP.
“In general, the BESS additions are timed to coincide with renewable energy additions to take advantage of potential efficiencies in procurement as well as potential tax incentives, or with reductions in capacity due to the retirement of existing thermal resources.
“The BESS installations are staged to take advantage of anticipated steep declines in the cost of these systems with 67% of the BESS capacity going into commercial operation in 2030 or later.”
A spokesperson for TEP said the finer details of all the storage systems to be deployed had not been finalized, but the portfolio did call for 1,400MW of storage between 2024 and 2035.
“Of course, it’s likely those storage resources will incorporate battery storage systems, however we’ve not issued any RFPs or signed any contracts for those additional resources yet,” he said.
In January 2020, a Wood Mackenzie report analyzed 43 utility Integrated Resource Plans in the US.
“The analysis reveals exponential growth in expected utility demand for battery energy storage system procurements as utilities adopt more aggressive clean energy portfolio strategies,” it said.