Microgrids in California

September 2020- This case study explores​​ potential ​number of​ microgrids that need to be installed ​in California in order to operate independent of the transmission lines.


With federal and state level legislation supporting microgrids, California can achieve a high level of microgrid and storage battery penetration by 2030 in the best case scenario. In order to achieve that, California grid ( IOUs and Community Choice Aggregators (CCAs)) will have to support development of an estimated 12,000 microgrids with an average size of 2500 kVA for a fully resilient grid.

California (2019):

  • Population: 40 million
  • Economy size: $3.2 Trillion 
  • Hourly average demand: 30 GWh
  • Minimum battery GWh to be installed for one hour duration: 30 GWh

Microgrid Quantity: 

2.5 MVA size each​ ---> 30GWh/ 2.5 MWh ---> 12000 microgrids 

Microgrid Cost:

12000 (quantity) * $2 million (avg cost of each unit) = $24 billion (​ including ​​​2 MWh battery)

Full capacity for 12 hours: $​144 Billion

​OR if Cars were to power the grid (same capacity)

  • Equal to (300,000 cars each 100 KWh batteries for one hour​)= 30 GWh​
  • Equal to 3,600,000, 100 kWh car battery for 12 hours
  • Cost of cars @ $50k ---> 180,000,000,000= $180 billion (for 12 hours)​

Microgrid Timeline:

  • Complete one per business day ( 250 days): 48 years
  • Complete six per business day ( 250 days) : 8 years 


  • $300/KWh average battery storage cost
  • $1.25 million for Interconnection, land, permitting, engineering and utility upgrades  
  • Does not include home battery capacity, other storage technologies and diesel or Gas generators 
  • Average load values are used
  • ​Does not account for substation upgrades
  • Study based on ​capacity for ​minimum 12 hour battery capacity duration​
  • Existing or future Solar PV connected to each microgrid will additionally support these Microgrids
  • Does not account for inflation 
  • Does not account for energy efficiency savings
  • Battery storage capacity to be about 40% of peak power


  • Security
  • Resilience 
  • Flexibility  ​​


  • Future load growth due to larger EV fleet
  • Land for Battery Storage and Utility Interconnection 

Future Topics:

  • ​Microgrid financing structures 
  • Bio fuels ​

VGG - Your partner in energy projects - September-2020

Get Insightful engineering expert opinion for energy and electrical Infrastructure, high voltage T&D, solar PV, EV charging stations, battery storage, microgrids.


Offices in Northern & Southern California
Vgg systems | High Voltage, PV Solar, Microgrids, Charging Infrastructure
Copyrights © 2022 VGG Systems. All Rights Reserved