In the case of an outage from a storm or other event, the microgrid is estimated to keep the fire station running in isolation from the electrical grid for two days.
McAlpine Creek Demonstration Project
To meet a growing interest in renewable backup power for critical facilities, such as police and fire stations, Duke Energy is testing a replicable microgrid model in a North Carolina neighborhood. Duke Energy’s McAlpine Creek Demonstration Project uses solar+storage to provide emergency power to Fire Station 24 in Charlotte, North Carolina, serving a neighborhood of about 14,000 residential and commercial customers. In the event of a grid outage, it is estimated that the clean, resilient microgrid will keep the station running in isolation from the electrical grid for two days.
Originally installed in 2009, the solar array at the fire station has a peak capacity of 50kW. A large 200kW/500kWh battery was installed several years later in 2012. The battery was initially installed for the purpose of smoothing electricity flowing onto to grid produced by the solar array. However, increased interest in microgrids from the military and communities looking for cleaner sources of backup power led Duke’s Emerging Technology Office to redevelop the system as an integrated solar+storage microgrid that could disconnect from the grid during disruptions to provide reliable emergency power to the fire station.
The equipment and software to create this resilient microgrid was installed in 2015, using mostly off-the-shelf pieces, so that the project could be easily replicated. Successful testing of this new solar+storage microgrid design could lead Duke to offer it as a standard service to all of its municipal customers.