Maxwell Technologies Blog
A Focus on Microgrids – Case Highlights from #ESACon19

A Focus on Microgrids – Case Highlights from #ESACon19

| Kim McGrath, Ph.D., MBA, Sr. Director of Business Development

ESA 2019

Since the launch of our grid energy storage solutions we’ve had an unprecedented level of interest in ultracapacitor energy storage for utility distribution, commercial and industrial (C&I), remote, and mission critical microgrids. The global energy storage-enabled microgrid market is poised for order of magnitude growth over the next 5 to 6 years to reach greater than 3GW power capacity.

I had the pleasure of being a panelist in the "A Focus on Microgrids” session at the Energy Storage Association Annual Conference and Expo in Phoenix last week. During the panel, I provided an overview of ultracapacitors (supercapacitors), which are rapid-response, high power energy storage devices that enable microgrids with a cost-effective strategy to address voltage and frequency stabilization, peak power shaving, instantaneous bridging and backup power, as well as other power quality services.

To elucidate the versatility of ultracapacitor storage, I shared three microgrid use cases that demonstrate the application of ultracapacitors for utility microgrids, remote off-grid industrial microgrids, and hybrid microgrids. For those who could not attend, I outline those use cases below.

Utility Microgrids: Frequency Stabilization and Seamless Transition from Grid Forming to Islanded Mode

Utility distribution microgrids are designed for autonomous control, reacting to grid level changes in frequency and voltage to stabilize power output. The primary use case for ultracapacitors is to maintain operational stability of the microgrid by providing near-real time frequency and voltage stabilization, however equally as important is supporting the seamless transition from grid mode to islanded mode.

During operational transition, switching transients may occur such that fast intervention is necessary to prevent microgrid relay and breaker trips. For a tier one utility microgrid located in the Western states, ultracapacitors are being deployed to provide fast responding frequency stabilization and voltage support during these grid to island mode operational transitions.

Remote Off-Grid Industrial Microgrids: Stabilizing Traditional Generation

Oil and gas production operations are prime candidates for conversion to remote microgrids for efficient operational expense and local reliability purposes. Driven by the need to reduce fuel consumption and operation and maintenance costs, examples of deployment of solar and other renewable energy generation alongside diesel and natural gas are becoming the norm. Benefits include control of reliability for critical power applications, direct economic benefits and quantifiable reduction in greenhouse gasses including CO2.

These sites utilize drilling rigs and other peak power intensive production equipment with high cyclic load fluctuations. These load characteristics decrease the operating efficiency of diesel generators by continuous ramp up and ramp down, with commensurate increase in fuel consumption. Batteries have been used to dampen power fluctuations to some extent. However, given the strenuous operating environment and high charge-discharge rate requirements, unscheduled and frequent battery replacements substantially drive up O&M costs.

Ultracapacitor energy storage systems provide an attractive technical and economic business case to deliver power support – providing rapid power smoothing to "condition” the load.  Ultracapacitor systems have extended lifetimes in extreme environments, delivering up to one million rapid power cycles.1 Economic benefits include reduced generator fuel consumption and $100’s/K year savings in battery replacements, labor, and other downtime costs.

Hybrid Microgrids: Delivering Mission-Critical Stacked Services

Mission-critical microgrids often require the delivery of a unique set of services – a "one size fits all” implementing a single storage technology does not deliver the most attractive technical and financial case. Instead, these sites require a hybrid ultracapacitor + battery system architecture to deliver optimal power and energy capability.

Ultracapacitor energy storage is coupled with Li-ion batteries, PV, and generators to enable delivery of services requiring both high peak power and high cycling as well as longer duration energy reserve. As rapid power delivery devices with long lifetimes, the ultracapacitor systems serve to stabilize microgrid switching transients, provide failsafe load bridging and ramping, shave peak power, and provide short duration PV power firming. The battery is dedicated to long duration PV smoothing and time shifting. 

By splitting the power (ultracapacitor) and energy (battery) functionality this system results in the use of less costly Li-ion batteries and less frequent battery replacement which in turn reduces project CAPEX and OPEX as compared to a battery-only solution.


Microgrid adoption is accelerating as new business cases and both hard and soft benefits are demonstrated, and I’m passionate about bringing new microgrid storage projects to life for the direct benefit of our customer base and in the broader interest of global sustainability.  

Maxwell looks forward to hearing from you to learn about how we can help maximize the value of your microgrid projects.

Also by this author: 5 Ways Ultracapacitors Operate in Utility Grids and Microgrids

1Results may vary. Additional terms and conditions, including the limited warranty, apply at the time of purchase. See the warranty details and datasheet for applicable operating and use requirements.

KimDr. Kim McGrath
Ph.D., MBA, Sr. Director of Business Development
About this author

Kimberly McGrath, Ph.D., MBA is senior director of business development and technical marketing at Maxwell Technologies. Dr. McGrath has spent her career in the field of energy storage applications and technologies. She has over 15 years of experience in the development and commercialization of energy storage solutions for electricity grid, industrial, and transportation applications, with specific expertise in building corporate strategic initiatives and business lines to profitably grow in emerging markets. She received her doctorate in chemistry from the University of Southern California and an MBA from The Paul Merage School of Business at the University of California, Irvine.

Get our blog posts delivered straight to your inbox

Opinions expressed in the content posted here are the personal opinions of the original authors, and do not necessarily reflect those of Maxwell Technologies, Inc. The content is provided for informational purposes only and is not meant to be an endorsement or representation by Maxwell or any other party. This site may also provide links or references to non-Maxwell sites and resources. Maxwell makes no representations, warranties, or other commitments whatsoever about any non-Maxwell sites or third-party resources that may be referenced, accessible from, or linked to this site.