Justin Day of Schweitzer Engineering Laboratories (SEL) explains how to minimize microgrid risk with vetted equipment from experienced professionals.
Risk is unavoidable when implementing a microgrid. Because of the complexity involved, projects can be delayed, budgets exceeded and equipment can fail or misoperate. The marketplace can also feel overwhelming.
To minimize risk and simplify the selection process, many experienced microgrid developers agree the number one way to avoid these often costly pitfalls is to choose proven technologies and solution providers.
A microgrid needs to provide resilient and reliable power. To do so, the complete microgrid system—including devices, configuration, communications, and so on—must be stable, proven, and thoroughly tested (using hardware-in-the-loop testing, if possible) before it is brought online.
In the utility sector, new technology goes through a prolonged vetting process because of the potential risks and hazards associated with unproven solutions. Using devices that have already undergone this process eliminates the risk of your microgrid equipment not meeting the standards of the utility it will interconnect to.
Consider applying the same protection, automation, and communications equipment in your microgrid that is used by the local utility. In addition to reducing the risk of misoperations and delays, this can greatly ease the approval process required for interconnecting with the utility. Also, utility equipment is often more cost-effective than unproven technologies.
New technologies are often touted as innovative solutions to old challenges or as being on the ‘leading edge’ of technology. However, using unproven technologies often results in delays and other unexpected outcomes. Before you decide to use a new technology, determine how much delay and what types of impacts are acceptable, and then decide whether the perceived benefits are worth the risk. A conservative approach is to also develop a detailed backup mitigation plan.
Even a proven device or technology is not necessarily proven for your specific microgrid application. Trying to make a device work for an unfamiliar or unintended application can cause misoperations, longer commissioning times, a failure to operate at a critical time, or the device not fulfilling the capabilities it was intended for due to unforeseen design limitations. Typically, the microgrid budget will have to absorb the costs associated with these unforeseen issues. Select devices that are fit-for-purpose. These will account for unique constraints in their design, which other technologies may not.
A microgrid is a combination of technology and engineering know-how. When planning your microgrid, be sure to account for the coordination and integration of the complete system. It is important that microgrid design engineers understand the microgrid from high-level operations down through low-level technical requirements.
One way for your solutions provider to ensure system functionality and operability before deployment is by using validated, real-time power system models. These can be used to prove system functionality during important operating scenarios and use cases. Detailed models with high-resolution and subcycle time stamping can give you high confidence that your microgrid will function in the field. Model reports can be used as part of the permitting and interconnection process, which will help eliminate a common barrier to bringing a microgrid online.
Being the first to try something new, like a restaurant or a mobile device, can be exciting, but it can also lead to regret.
One of the defining traits of a microgrid is the ability to island. Uninterrupted islanding requires high-speed control to maintain system stability, as well as adaptive protection for changing fault currents, all of which needs to happen seamlessly to prevent a blackout. Interfacing with power electronics and accounting for the variability of renewable generation sources, such as wind and solar, each pose their own unique challenges. Addressing these interrelated protection and control issues requires comprehensive knowledge and experience when designing and implementing a microgrid. Hire engineers and professionals who have electric utility experience and the know-how to keep the lights on. Be sure they can demonstrate that the microgrid will work in accordance with your expectations.
A proven solutions provider should have demonstrated experience and should also have references for similar projects. Take the time to vet references, and also verify that providers have licensed professional engineers on staff, as well as relevant certifications.
Being the first to try something new, like a restaurant or a mobile device, can be exciting, but it can also lead to regret. The success of your microgrid is too critical to leave to that chance. Use standard, off-the-shelf, utility-grade control and protection equipment and engineering services from experienced professionals to ensure a successful and timely implementation. When it comes to choosing the control and protection devices and engineering providers for your microgrid, there is no substitute for experience.
Justin Day is the senior marketing program manager at SEL. Download SEL’s free white paper “Implementing a Microgrid Using Standard Utility Control Equipment.”