Update on the Twentynine Palms Marine Base microgrid
In 2009, General Electric was awarded $2 million for a technology demonstration contract from US Department of Defense’s Environmental Security and Technology Certification Program (ESTCP) Office to test and validate a microgrid system controller at Twentynine Palms Marine Base in California, the largest marine base in the country. Scheduled to be fully operational in early 2012, this microgrid is capable of islanding roughly a third of the marine base’s total load, while simultaneously meeting DOD’s criteria for cybersecurity.
Twentynine Palms already has 7 acres of solar photovoltaics (PV) that total more than 1 MW, as well as a gas-fired cogeneration plant in excess of 7 MW. In the future, additional solar PV, fuel cells and advanced energy storage systems may also be added to the marine base’s on-site resource mix. GE has helped design a microgrid control strategy– for the largest microgrid in the U.S. among DOD sites – managed by a platform based on existing GE controls already utilized for smart substations. The controller is flexible and can manage other “smart” distributed resources, including inverter-based sources, through proprietary algorithms.
Local generation sources, power from the utility grid, and the marine base’s load demands will all be monitored and coordinated using the configurable logic of GE’s Multilin Universal-Plus relay (See Figure). The relay’s algorithms will enable mixes of renewable energy, fossil fuel generation, and grid power to be balanced at different times. In addition, loads can be better predicted and prioritized during periods of higher consumption or islanded conditions. With this controls architecture in place, Twentynine Palms can optimize on-site resource while in grid-connect mode, but also extend its operations capacity and maintain high performance in an off-grid situation. Since the GE controls technology is flexible, it also may be able to be deployed in mobile microgrid applications. (The company is already deploying the same controller in a smaller remote community microgrid of approximately 4 MW (winter season) in British Columbia known as “Bella Coola.” For more details, please visit http://www.genewscenter.com/Press-Releases/Clean-Energy-Powers-Bella-Coola-B-C-2ac3.aspx)
GE and the ESTCP Office wish to certify the technology using the Twentynine Palms base as an evaluation vehicle for future microgrid development enabling widespread implementation across the more than 400 bases within the US. The microgrid with its advanced supervisory control technologies is being viewed as one of the premier examples of the environmental and energy surety technologies yet to be deployed by the military. It is one of the first to incorporate variable renewables and is beyond the scale of most pilot projects, which typically fall in the sub-megawatt range.