Federal power systems support critical infrastructure and missions at the forefront of national defense operations. With the weight of national security on the line, truly resilient power is essential for these federal entities. Unfortunately, the main power grid can’t guarantee resilient power for these locations 100 percent of the time.
Main power grids have aging infrastructure and are becoming a prime target for physical damage and cyberattacks, which have the potential to shutter the grid and cause unprecedented consequences. Military operations have existing backup generation on-site, but these backups aren’t enough to sustain ongoing base operations for days at a time. Existing equipment is often not configured effectively or maintained properly as stand-alone assets, but it does have the potential to be leveraged for energy-security measures in military installations by being integrated into an advanced microgrid.
Many military bases have pursued advanced microgrids to help support their power needs, but Fort Belvoir in Virginia is the first to integrate existing generation sources into the system to reduce capital costs and improve resiliency. As such, it serves as a model for future power systems at mission-critical military bases.
The Department of Defense’s (DoD’s) Environmental Security Technology Certification Program (ESTCP) knew maintaining operations in the face of a crisis was crucial for any military operation, and it was determined to demonstrate the viability of implementing advanced, cybersecure microgrids at military operations that use existing on-site generation and infrastructure. For this application, ESTCP was interested in proving a cybersecure microgrid could reduce operating costs for the base while sustaining critical missions, ideally becoming a replicable model for future DoD installations.
Understanding the Fort Belvoir microgrid
To achieve these goals, ESTCP selected a Chicago-based provider of equipment and services for electric power systems to develop an advanced cybersecure microgrid with the capability of seamlessly islanding from the main grid and properly isolating itself in black-start conditions. The base’s existing generation assets were a crucial component to the microgrid’s design, and the system used the base’s existing utility connection.
Building the system around available fixed and mobile generators eliminated the need to bring new, permanent generation into the equation, and it helped expedite the deployment and decrease overhead costs for the system. These existing assets had sufficient generation capabilities to support 13 critical buildings in a subsection of the base in the event the microgrid had to island from the main grid.
Besides integrating existing generation into the microgrid, the system relies on a distributed, cybersecure microgrid control system that provides automated, intelligent decision-making coupled with embedded cybersecurity protection. The control system was the first of its kind to receive an Authorization to Operate from the DoD, verifying it would be effective and secure enough for a federal microgrid. The microgrid control system directs and protects every asset within the microgrid, seamlessly balancing and optimizing the system.
Setting the stage for future deployments
The microgrid deployment culminated in two testing events to verify the system would operate as intended. Following the tests, results proved the microgrid could successfully island from the main power grid without hindering any critical operations at the base. Demonstration of the microgrid also validated that the system could support the base’s critical needs for multiple days in the face of an outage on the main grid, and it set the stage for future exploration in military microgrids using existing on-site generation.
Expected to be the first of many similarly designed microgrids, it is important to understand the lessons this project brought to light to simplify future deployments — military or otherwise — and to help ensure microgrids can come online faster.
Lesson: Microgrids need supportive stakeholders
Every microgrid will have a variety of stakeholders: the owner, the developer, the utility etc. Connecting with all stakeholders throughout the project is necessary to understand their expectations of the final system, identify potential roadblocks in the deployment schedule and ensure everyone is satisfied with the end result. It also helps prevent conflict and delays with the deployment. Additionally, finding a champion to actively support and promote the project internally is critical to the effort’s success. This champion can help facilitate stakeholder conversation, use their influence to guide progress and deconflict issues as they arise.
Lesson: Integrating existing infrastructure can be challenging
The majority of microgrids will not be completely greenfield installations. Often, a microgrid is being integrated into an existing electrical system, and not all existing electrical infrastructure in its present state is ready to support a microgrid.
Before designing a microgrid around existing equipment, it’s important to identify any potential limitations. Within the Fort Belvoir microgrid, the system ultimately benefited from using the preexisting generation and other assets, but adjustments were made to the intended design to integrate everything properly. Key areas of consideration regarding infrastructure include:
- Existing electrical distribution: When integrating existing assets into a new microgrid, some key areas of focus should be the size and status of existing transformers, whether there is imbalance on the system, what existing generation assets exist and where the present utility feeder connection is located in relation to the microgrid site. All of these factors can have a big impact on the microgrid’s design.
- Existing generation: Generators are often the backbone of a microgrid. If the new system is planning to integrate an existing generator, be sure to examine its present operational state. Does the generator work properly? Has it been maintained? What can the existing generator controls do? These may seem like simple questions, but understanding the state of existing generation early on can help avoid headaches during the deployment process.
- Physical location: Brownfield microgrids can come with a variety of challenges, including identifying where any new distribution equipment can be safely and effectively placed to support the system. Before designing the system, be sure to review location and growth constraints that could affect the overall size of the microgrid.
- State of the communication network: It’s very likely a present network at the microgrid’s location is serving existing assets. Will that network be enough to support the communication needs of a microgrid? Typically, the existing network will not have been designed to support a microgrid control system, and updates will need to be made.
Lesson: Defining operation requirements of the microgrid
After assessing existing infrastructure, it’s important to identify the ideal use cases and system applications the microgrid could achieve upon completion. Below is a list of standard use cases and complex use cases. Not every microgrid can meet each of these. Outlining the desired operational requirements early on helps the microgrid integrator identify any design limitations associated with the existing infrastructure being used. In some cases, operational requirements may need adjusting to better match the capabilities of existing infrastructure.
Standard Use Cases
- Grid-tied
- Island
- Transitions
- Black start
- Intentional island
- Island to grid-tied
- DER optimization
- DER monitoring and control
Complex Use Cases
- Storm preparedness
- Islanding with renewables (Green mode)
- Peak-shaving
- Curtailment
- Renewable smoothing
- Frequency regulation
- Power factor correction
Lesson: Multi-Layered contingency handling
What happens when a generator doesn’t start? Or when communications fail? A microgrid system should have multiple layers and contingency-handling tools in place to help the microgrid stay online and operational when the end-user needs it most. Three areas to focus on are: resilient equipment, distributed design and intelligent controls.
No matter the equipment chosen to support the system, consider the physical challenges of the area. Must the equipment maintain operation in extremely cold or extremely hot conditions? Does it need to be submersible and withstand challenges associated with rain or snow? Does the equipment require an uninterrupted power supply to power control equipment in the face of an outage?
Next, look at the system design. The goal should be to eliminate a single point of failure. A distributed control architecture can improve redundancy and resilience in a microgrid. This includes the electrical distribution, generation equipment, network and controls for the system. Consider whether the system would benefit from a fiber-loop network that redundantly connects all the equipment.
Every microgrid deserves an intelligent control system capable of withstanding multiple levels of contingencies. Even the most beautifully designed systems can experience operation challenges, but a robust control system automatically adapts to prioritize operational requirements.
Lesson: Proper cybersecurity considerations
When considering cybersecurity within critical facilities, it’s important to recognize the evaluation is really of a system of systems and not just a single piece of equipment. If left unprotected, these systems are vulnerable to attack. The question isn’t if there will be an attack, but when. It is estimated that the Department of Defense thwarts 36 million dangerous emails per day [1], clearly illustrating the constant threat to DoD systems.
Cybersecurity is critical for a microgrid system, and it’s very easy to get wrong. Complex security protocols can often result in fragile systems, which limits resilience. The more devices, software and communications in place to support cybersecurity, the greater the number of intrusion points.
The best way to provide the security a microgrid and its environment requires is to pursue a proven energy-management system, such as a cybersecure microgrid controller with built-in security. When a control system has multiple layers of defense embedded in its design, it’s better equipped to respond appropriately when a threat presents itself.
As microgrids become more prevalent around the world, the industry is able to pursue simplified solutions to meet energy goals thanks to experienced microgrid integrators and owners sharing their best practices for deployment and design. Kicking off a new microgrid effort may seem intimidating and overwhelming, but know that the process doesn’t have to start with a blank piece of paper.
Remember, complex solutions aren’t always the best choice; there is no reason any microgrid needs to reinvent the wheel. Resources are available from experienced organizations that have been through this before and from microgrid integrators that can help lighten the load when it comes to actually designing and implementing an advanced microgrid.
Stephanie Pine is director of strategic accounts, at S&C Electric Company. Pine has spent the last 10 years in power and energy R&D and microgrids. She has served as the project manager on several deployed military and commercial microgrid projects, as well as on a number of government microgrid research projects. Prior to entering the power and energy space, she worked in higher education, focusing on revenue generation and organizational process and policy development. Pine is a graduate of Oregon State University and holds a Lean Six Sigma black belt.
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