San Diego Jumpstarts Microgrid Projects to Boost Resilience

The City of San Diego has started constructing its first solar microgrid project. The partnership between the city and Shell New Energies marks the beginning of a series of eight microgrid projects set to be installed across various municipal buildings.

Green energy concept with solar cell panels, nuclear power, and wind turbines. Image used courtesy of Adobe Stock

 

Microgrids for Cities

Microgrids are localized energy systems that operate independently or in coordination with the main grid, utilizing renewable energy sources and often incorporating energy storage technologies. Unlike the traditional centralized grid, microgrids can function autonomously, generating, distributing, and managing electricity within a defined geographical area.

Microgrids offer a promising avenue for cities and businesses to bolster their resilience, cut emissions, and realize key policy objectives, such as brownfield redevelopment and smart city implementation. 

Example of a microgrid. Image used courtesy of Siemens

 

Microgrids can operate on various energy sources, including renewables, natural gas-fueled turbines, emerging technologies like fuel cells, and potentially small modular nuclear reactors once commercially available. During weather or security-related grid disruptions, microgrids can power critical facilities, ensuring the continuity of essential services.

Microgrids can be the primary electricity source for crucial institutions such as hospitals, universities, or entire neighborhoods. While single-user and campus microgrids have existed for many years, there is a growing interest in more sophisticated systems within cities. These advanced microgrids aim to integrate diverse energy generation resources and accommodate varying loads while serving multiple users. They can align with environmental objectives and emergency response plans, making them increasingly sought-after solutions for modern urban settings.

 

Boosting Grid Resilience

Microgrids are gaining popularity in California as they provide independence from the traditional electric grid.

The inaugural microgrid project in San Diego was revealed at the Southcrest Recreational Center in South County, marking the beginning of an ambitious $5.5 million public-private partnership between the California Energy Commission and Shell New Energies. 

The significance of this first project is that it will allow the Southcrest Recreation Center to maintain an uninterrupted power supply during outages. It will also enable the city to rely entirely on renewable energy generated and stored onsite. 

All eight microgrids will be powered by solar energy generated from rooftops or carports and have storage systems with lithium phosphate batteries. Any surplus energy produced during the daytime ‒ when electricity costs are low ‒ will be stored in the battery systems for later use. 

This approach is expected to create significant cost savings for the city. By deploying the stored electricity between 4-9 pm, during peak demand and high electricity prices, the city can mitigate stress on the grid and reduce expenses. 

Officials estimate that over the 25-year agreement, these eight microgrid systems will collectively save the city and its taxpayers approximately $6 million.

The stored electricity from the microgrids can also be utilized during neighborhood power outages to enhance energy resiliency and ensure continuous access to electricity in surrounding areas.

The city has plans to install electric vehicle charging stations at all municipal facilities that can utilize power generated from the microgrids. This integrated approach furthers the city’s commitment to sustainability and reducing carbon emissions.