Microgrids are one tool in the energy toolbox to combat the threat of natural disasters


Jared Leader, manager of Industry Strategy at the Smart Electric Power Alliance (SEPA), speaks about their latest research and the role of microgrids in increasing grid resilience.

The stats don’t lie; natural disasters are on the rise and their severity is increasing. In 2019, the United States experienced 14 natural disasters, each causing damages of over $1 billion. These disasters included severe weather events, hailstorms, wildfires, flooding, tornadoes, tropical storms, hurricanes and earthquakes, all of which can threaten the reliability and stability of the electric power system.

Globally, the World Health Organisation reports that 90,000 people are killed, and close to 160 million people worldwide affected annually by tsunamis, landslides, hurricanes, floods, wildfires, heat waves and droughts.

Around the world, certain types of disasters are anticipated to increase in frequency and scale. These include:

  • Wildfires: California and other US states on the West Coast and in the Mountain West are dealing with heightened and extreme droughts, dryness and wildfires.
  • Hurricanes: North Carolina and other US states in the Southeast are experiencing more frequent tropical storms and hurricanes.
  • Other: Countries in Asia and Africa are also suffering from extreme weather such as severe typhoons, cyclones or heat waves. Recent heat waves occurring in India and across countries in Asia are also causing a heightened awareness of the types of threats that can negatively impact the energy system.

The need for resilience

As a result of the increased severity of natural disasters, some utilities and government entities are turning to microgrids to power critical systems and facilitate the integration of distributed energy resources (DERs). Microgrids are one tool in the energy toolbox among many which can be harnessed to increase grid resilience against natural disasters.

A word of caution, however, is that it is critical for stakeholders to define the problem at hand because a microgrid may not always be the right answer. Only by engaging stakeholders – city, local government and community members – can utilities determine exactly what the anticipated need for a microgrid is, the scope of the potential benefits, and the proposed duration of alternative supply.

Although this article extensively details a framework for planning microgrids, it’s important to understand the other resilience tools and strategies that utilities, communities and customers can use to increase grid resilience. These strategies can include undergrounding T&D infrastructure, managing vegetation, insulating wires, building system redundancy and hardening substations and feeders.

Microgrids as a resilience service

The Smart Electric Power Alliance (SEPA) works with a variety of stakeholders to research and develop industry strategies to facilitate microgrid design, planning and modelling by looking at microgrids through three lenses of resilience: for the individual customer, community and/or macro-grid service.

Under certain circumstances, microgrids may only act as a single solution for a specific customer or critical facility. A deployment of microgrids that serve single critical facilities was seen across Puerto Rico, post-Hurricane Maria, providing access to power for remote areas to public good services and lifelines – such as schools, police stations and hospitals – through the addition of solar, battery storage and microgrid controllers.

In more novel circumstances, microgrids may involve multiple stakeholders acting as multifunctional systems that can provide individual customer benefits or critical facility needs during emergency operations while providing grid services during normal operations.

Through deliberate planning with a multistakeholder process, it is possible to plan and deploy microgrids that provide benefits not only to the community or individual critical facilities, but also to the systemwide grid. Utilities are finding the most success by partnering with their communities and customers to build multi-functional microgrids; projects that provide mutual benefits and goals for customers, utilities and communities. Microgrids that can transition from serving as a utility grid resource during normal operation to improve grid reliability, capacity and potentially defer distribution asset investments, to providing a source of back-up power for a single or group of facilities deemed critical by the community during a prolonged outage.

The key is listening to the differing needs of customers, utilities and communities to determine what each values the most from resilience. For customers, it may be to avoid power interruptions and to maintain critical operations and economic productions; For utilities, to maintain safe and efficient operations with highly reliable service; and for communities, to avoid or minimise power interruptions to critical services.

Many industry stakeholders are experiencing difficulty in financially justifying microgrid projects without stacking the value of individual customer, macro-grid and community resilience benefit. Microgrid projects which solely serve a specific customer benefit, or a community need, aren’t always going to work financially. Hence the importance of a thoughtful approach for planning microgrids with the focus of gaining community buy-in and partnership.

Not without its challenges

Perhaps the two most challenging parts of planning and building a microgrid are addressing who pays, and who benefits.

Utilities are under pressure to demonstrate system-wide benefits in order to propose rate recovery for installing microgrid assets. Again, through the proposed stakeholder engagement process, discussions with the regulatory commission in each region can determine the best structure for the project. In some cases, co-ownership may be considered.

The process below developed by SEPA provides an opportunity for utilities, customers and community stakeholders interested in a microgrid to determine their priorities, challenges, deployment scenarios and ultimately to identify joint investment and ownership opportunities.

The SEPA microgrid planning framework

SEPA recently published a Microgrid Playbook which lays out an approach to address microgrid planning and deployment for resilience characterised by four key elements or practices, namely:

  • A holistic, community-centric approach which is intended to be used by utility and government entities to identify and evaluate potential microgrid deployment to increase resilience against natural disaster.
  • Threat and solution-specific: Offers a threat-specific (natural disasters) and solution-specific (microgrids) approach to looking at resilience.
  • Demonstrated in the field: Based on SEPA’s work engaging with utility and government entities in Puerto Rico and on the West Coast of the US to explore plans for microgrids to increase resilience.
  • Best used in coordination: Stakeholders can use this microgrid planning tool in coordination with emergency response planning activities such as energy assurance planning, emergency response and energy restoration.

The five steps of the SEPA Microgrid Playbook: Community resilience for natural disasters

Step One: ID critical sites

  • Engage with stakeholders to determine which critical facilities and customer types are targets for microgrids.
  • Talk with individual end-use customers to see who has or is interested in onsite generation that can be leveraged for a microgrid.
  • Survey stakeholders to understand which sites may have space amenable to microgrids.
  • Sit down with stakeholders to gauge which customers and/or facilities may get priority for resilient power via microgrid.
  • Examples include hospitals, correctional facilities, (waste) water treatment facilities, schools, fire, police, radio towers, evacuation and shelter sites.

Step Two: Find high risk areas

  • Coordinate with state, local or federal emergency preparedness groups to identify public emergency preparedness maps for reference and to determine the areas which have the highest natural disaster impact risk and which areas will face the harshest impact.
  • For example – flood-prone areas, high wind/ dry vegetated areas, earthquake shock and liquefaction areas, etc

Step Three: ID sites served by circuits in affected zones

  • Coordinate with utility entities to evaluate the practicality of interconnecting DERs on specific portions of the grid that are vulnerable to natural disaster.
  • Talk with individual end-use customers and other stakeholders to understand which existing sites near vulnerable areas have onsite generation and could be retrofitted for microgrids.
  • Evaluate and analyse disaster-prone areas with capacity and reliability constrained areas to determine if there were dual function opportunities for a microgrid to both provide a grid service and a community need.
  • For example – an initial map and list of potential microgrid sites for community resilience against natural disasters.

Step Four: Size microgrid to load profile

  • Collect data to analyse the specific site’s load profile and evaluate the appropriate size of the generation assets.
  • Engage stakeholders to determine how long the microgrid needs to run. The specified and targeted duration need of the site will dictate the necessary size and portion of renewable/fossil-fuel is necessary to meet the application.
  • Examples include preliminary microgrid design and modelling; low, moderate, and aggressive-renewable microgrid scenario systems sizing; and cost estimations.

Step Five: Evaluate deployment scenarios

  • Look at geographic and demographic factors such as population density and land and environmental restrictions to prioritise and determine where the microgrids will have the most impact within the city, community or neighbourhood.
  • Survey the disruption-prone and natural disaster risk areas and determine if the microgrids should be deployed inside the disruption-prone area to provide accessibility to the community or outside the disruption-prone area to avoid physical damage while still serving as a designated resiliency hub/facility.
  • Look at the landscape of the pockets of critical load to determine whether a site specific microgrid or a transformer-level or community-level microgrid makes the most sense. If there is a cluster of critical loads, a transformer-level or community-level microgrid may make the most sense.
  • For example – Inside vs. outside the disruption-prone area; or site specific vs. transformer-level vs. community level

Maximising microgrid benefits requires early and frequent communication between the impacted utility, customers, and the community. It involves convening the right stakeholders and soliciting input from the very beginning to bring the most benefit to all. Ultimately, identifying and planning potential microgrid sites for community resilience requires identifying critical infrastructure, defining vulnerabilities, modelling load profiles, and evaluating various deployment scenarios on the grid and within the community, while the benefits accrue to address customer, utility and community needs.

SEPA’s integrated approach offers utilities and government entities a starting point for developing holistic microgrid and resilience planning. SEPA encourages interested parties to iterate on and adapt this process in their own jurisdictions.

SEI To download SEPA’s most recent Microgrid Playbook and Case Studies, follow this link

About Jared Leader

Jared Leader joined SEPA in 2017. In his role, he develops strategic plans for programs, products, and service offerings for utility and industry stakeholder members and clients that facilitate the integration of distributed energy resources, non-wires alternatives and microgrids onto the modern grid. He leads SEPA’s Microgrids Working Group and co-led the D.C. Public Service Commission’s grid modernisation working groups. Leader has a MS, Energy Policy and Climate from Johns Hopkins University, and a BS in Civil and Environmental Engineering from the University of Virginia.

About SEPA

The Smart Electric Power Alliance (SEPA) is dedicated to helping electric power stakeholders address the most pressing issues they encounter as they pursue the transition to a clean and modern electric future and a carbon-free energy system by 2050. For more information, visit www.sepapower.org. Don’t miss the 2020 SEPA Grid Evolution Summit, July 28-30, which will feature virtual sessions such as Maximising Microgrids.