Fort Carson in Colorado Springs is one of several microgrid projects underway on U.S. bases under the SPIDERS (Smart Power Infrastructure Demonstration for Energy Reliability and Security) program. It is a large base with about 14,000 residents, and covering 550 km2, with additional firing ranges nearby.
The base as a whole has an ambitious plan to become a net zero facility using huge PV resources, potentially over 100 MW, as well as wind, ground-source heat pumps, biomass, and solar water heating. The microgrid project is intended to keep a group of central base facilities operating without grid power as an island, in the event of grid failure.
Currently, the SPIDERS Microgrid is composed of existing assets, a 1 MW PV array and three diesel generators with a total power of 3 MW, and 5 electric vehicles (EVs) with V2G capability. A 3-day operational demonstration took place in October 2013 to assess the robustness of the design. The PV and 4 out of 5 EVs were successfully connected during the field test.
The challenges which were faced during the implementation of the project and the demonstration were solely issues related to system ownership and communication. For instance, a 2 MW array should initially have been integrated to the microgrid. Despite attempts to obtain a site access agreement to the total PV array, it was already too late to include it into the system configuration which might restrain the future use of the microgrid when islanded.
The project should be fully operational in 2014. Other microgrid-related technology demonstrations are also in progress at Fort Carson, most notably its demonstration of medium duty electric trucks. The U.S. military has about 200,000 small trucks in its fleet, and they are considered a promising source of electricity storage for military microgrids both at home and forward bases.