Microgrids come in all shapes and sizes, allowing power to reach a wide range of consumers and locations. They can be broken into categories based on their connection to the main grid (grid connected or off grid) and type of ownership (facility or community). Their benefits can vary depending on the category, but in general, all categories of microgrid provide increased reliability, resiliency, and security, and reduce the use of fossil fuels.
Although microgrid implementation projects differ in some regards, such as their business model and scope of work, they still encounter many of the same challenges. Focus on the primary microgrid implementation challenges and how you can overcome them — by sizing microgrids carefully and correctly, overcoming design challenges using project-specific engineering studies and calculations, and using software and simulation tools.
Preliminary sizing is a key action because it determines potential solutions and the microgrid’s economic viability. Every microgrid project differs in areas like size, power and voltage levels, location, and cost criteria, which all affect the microgrid’s design. Using microgrid sizing software, it’s possible to model the physical and economic environment and context to discover microgrid component information to minimize a given cost criterion.
In the preliminary sizing phase, economically viable scenarios are determined. These then require project-specific engineering studies to establish equipment features and ensure the microgrid works correctly during operation.
These 10 calculations and studies are crucial to perform to overcome design engineering challenges:
- Perform a sizing study to determine the best combination of distributed energy resources
- Provide identification and a detailed description of the operating philosophy with all the microgrid’s operating modes. Whether a microgrid is designed to be able to disconnect from the main grid (islanding), for example, has design consequences for its protection and earthing scheme
- Calculate the load flow in all possible operating configurations to assess the current flows and voltage levels in the microgrid’s power system during operation
- Calculate the short-circuit current to discover the minimum and maximum short-circuit current levels that could occur in case of a fault
- Conduct a protection philosophy and coordination study to protect personnel and equipment and coordinate protection tripping sequences and curves
- Manage the neutral earthing system to ensure the proper operation of microgrids
- Conduct a dynamic stability study to evaluate, predict, and monitor the microgrid’s power system’s dynamic behavior related to transient events
- Determine electrical equipment specifications and create a single line diagram (SLD) — these are needed to order equipment and are the primary output of power systems engineering studies
- Configure microgrid control systems — functional analysis and design — which are a crucial element for microgrids to be completely operational
- Identify the optimal settings for energy management and perform robustness analysis
- Test and commission the microgrid to ensure it behaves as expected
In addition, there are many software tools, particularly microgrid computer simulation models, that guide through the next step of transitioning from design to operation.
The microgrid market continues continue to expand. By addressing microgrid implementation challenges now, you’ll be prepared to take advantage of the growing market’s new opportunities.
For a more in-depth look at implementation issues and practical advice on how to address them, read “Microgrid Implementation Challenges and Key Technologies.”