Location: United States, Hawaii, Maui

Application: Ramp Rate Control, Responsive Reserve

Earning Revenue via Multiple Value Streams: Kaheawa Windfarm Dynamic Power Resource (DPR®) Energy Storage


First Wind built a second phase to the Kaheawa Wind Project (KWP II) adding an incremental 21 MW of wind generation on the island of Maui on the Maui Electric Company’s 69 kV electric system. In order to mitigate the effects of wind volatility on an island grid, Xtreme Power designed a 10 MW Dynamic Power Resource® (DPR) to integrate with the 21 MW KWP II facility operating on a 80-200 MW grid. Wind development in high penetrations requires grid flexibility. this demonstration on Maui, where wind was already 30% of nighttime energy demand provided a means for the grid to manage higher levels of renewable energy.


Xtreme Active Control Technology™ (XACT™) will prioritize the set of services to enable the DPR to dynamically respond to the conditions on the island grid. the DPR comprises 10 MW with a dynamic range of 20 MW and a 45-minute storage duration, designed to provide Rresponsive Reserves and respond to Frequency Regulation via AGC and Frequency Response without AGC to keep grid frequency deviations within ±0.1 Hz. The Ramp Rate Control will be fixed to ensure the change of output stays within the ± 1 MW per minute operating parameter set forth in First Wind’s PPA.


The Kaheawa II project marks Xtreme Power’s third project with First Wind, following the KWP I demonstration project and the 15 MW Kahuku installation. This project demonstrates that storage increases the reliability of the island grid, opening the region to additional renewable energy projects and setting a precedent for the effective integration of renewable projects in the future. Most importantly, the DPR is enabling the KWP II wind park to effectively deliver power to ~7700 homes on Maui annually. For more information, visit www.younicos.com.

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