Thermal energy storage systems, which shift electricity for air conditioning and process cooling from on-peak to off-peak time periods, have proven over the last 60 years to be one of the most cost-effective, reliable and feasible means to reduce critical on-peak demand and can also achieve energy efficiency1. The purpose of thermal energy storage is to set aside previously generated electricity for beneficial use later. Another consideration for the value of TES is that it can add to intermittent renewable loads such as wind energy, which is delivered mostly off-peak2. Also, a wider deployment of TES peak load shift will help the grid load factor.
1Source energy reduction from 24 - 45%, Site energy 12 - 20% (non TDV, if TDV values can be higher depending on application, Emissions - source 30 -50% from "Source Energy and Environmental Impacts of Thermal Energy Storage" published by California Energy Commission.
2California wind power produced at 254.6 MW (10.2% of wind's rated capacity of 2,500MW) at the time of peak demand (on July 24th, 2006) and over the preceding seven days (July 17-23) the facilities produced at 4% of rated capacity. CEC Report