56MW energy storage project features lithium NMC energy storage system

Operational since January 2016, the two new systems, along with a Kokam 16MW / 5MWh Lithium Titanate Oxide (LTO) ESS system deployed in August 2015, provide South Korea's largest utility, Korea Electric Power Corporation (KEPCO), with 56MW of energy storage capacity for frequency regulation. These three systems are part of the world's largest ESS frequency regulation project, which is scheduled to have deployed 500 MW of battery-based energy storage when it is completed in 2017.

In addition to improving grid reliability, the Kokam ESSs will enable KEPCO to improve its operation efficiency by reducing its need for spinning power generation reserves. This will allow KEPCO to shift energy generation to lower cost, more efficient power plants and decrease 'wear and tear' on all its power plants. For example, the three Kokam ESSs will deliver an estimated annual savings of $39m in fuel costs, providing fuel cost savings five times larger than the ESSs' purchase price over the systems' lifetimes. In addition, by reducing the amount of fossil fuels burnt for frequency regulation, the Kokam ESSs will help reduce KEPCO's greenhouse gas emissions.

"Kokam specialises in the development of advanced battery technologies for the world's most demanding Energy Storage System applications, including frequency regulation, which needs systems that deliver high power, fast recharge rates and long cycle lives," said Ike Hong, vice president of Kokam's Power Solutions Division. "Our Energy Storage Systems provide KEPCO with the performance it needs to precisely and cost-effectively regulate frequency on the South Korean grid, helping it ensure the stability of this grid, improve its operational efficiency and lower its greenhouse gas emissions."

"In the U.S. and Europe, Kokam has already garnered recognition for its exceptional Lithium Ion battery technology. Against stiff competition during the KEPCO frequency regulation project procurement process, Kokam proved its competitiveness after a comprehensive economical and technical analysis," said Hwang Woohyun, Ph.D, KEPCO's senior vice president, head of Innovative Energy Business Division. "Kokam's 56MW of Energy Storage Systems are making a major contribution to the stabilisation of our grid and we hope to continue to cooperate with Kokam to develop energy storage projects that improve grid reliability, lower our operational costs and reduce our environmental impact."

The 24MW and 16MW Lithium NMC ESSs utilise Kokam's innovative Ultra High Power NMC battery technology. Designed for high power energy storage applications, such as frequency regulation, wind or large solar power system ramp rate control, Uninterrupted Power Supply (UPS) and voltage support, Kokam's Ultra High Power NMC battery technology delivers:

• Higher energy density: This higher density enables 2.4MWh of energy storage to be installed in a 40 foot container, compared to 1~1.5MWh of energy storage for standard NMC batteries.
• High power cycle life: Ultra High Power NMC batteries can last up to 10,000 cycles, compared to 3,000 - 5,000 cycles for standard NMC technologies, increasing an energy storage system's expected life.
• Better charge, discharge and max power rates: Ultra High Power NMC battery technology has charge, discharge and max power rates of 4C, 8C and 15C, compared to 2C, 3C and 4C for competitors. This enables Ultra High Power NMC systems to receive and dispatch more power when needed.
• Improved heat dissipation: With a heat dissipation rate that is 1.6 times better than standard NMC technologies, Ultra High Power NMC batteries can be used at a higher rate for longer periods of time with no degradation in battery life or performance.

The systems also use Kokam's KCE 40 foot container, which features a direct cooling design, in which the container's Heating Ventilation and Air Conditioning (HVAC) system only regulates temperatures inside the system's racks rather than the entire container. This results in 70% less air-conditioning auxiliary load than standard containers.

"With some of the most innovative battery and other energy storage technologies on the market, 26 years of lithium-ion battery system manufacturing experience and 95MW of energy storage system capacity in operation around the world, Kokam has positioned itself as a leader in the rapidly growing energy storage system market," said Hong. "For applications such as frequency regulation, renewable energy smoothing, transmission and distribution investment deferral, demand response and peak load shaving, Kokam provides customers with advanced battery and other energy storage systems technologies that deliver superior performance at a competitive price."