The Konterra Solar Microgrid Project in Laurel, Maryland, taught us important lessons we will use in future microgrid projects.
By C.J. Colavito, Director of Engineering, Standard Solar
As the solar industry searches for solar + storage solutions, microgrids continue to be a hot topic at educational conferences across the country.
A microgrid is a group of interconnected loads and distributed-energy resources within clearly defined electrical boundaries that acts as a single, controllable entity with respect to the grid. Furthermore, it can connect and disconnect from the grid to enable it to operate in both grid-connected or island-mode.
But designing and installing a microgrid does present its own specific challenges because of its inherent complexity. During Standard Solar’s work on the Konterra Solar Microgrid Project in Laurel, Md., we learned valuable lessons on what it takes to make such projects successes:
1. Coordinate the financial model with the project’s technical details.
To have a successful microgrid project, the cost-benefit analysis must be done with painstaking precision.
This includes totalling up the potential revenue streams—incentives, avoided costs, grid-support payments and the value of backup power/resiliency, and subtracting the costs associated with running and maintaining the system, including everything from the energy consumed by the system and operations-and-maintenance to ISO dispatch fees and insurance.
Customers are going to want to know exactly what they can expect in revenues, so it’s critical to take into account all these factors. Which naturally leads into No. 2 on the list.
2. Manage customer expectations about what the technical capabilities and financial performance of the microgrid will be.
We’ve all been in customer meetings where we’ve talked about the eventual performance of the system and what the client can expect. But what we sometimes don’t do is listen to what the client is telling us with regard to their expectations of what the system will do. And if you miss this critical piece of the project’s development, it leads to headaches down the road.
Understand what customers are expecting, and educate them if their expectations don’t match the reality of how the microgrid will function. And because the solar industry is changing rapidly every day, talk to them about engineering flexibility into the system to accommodate new technologies and changing market conditions in the future.
3. Select the appropriate storage technology for the application.
Choosing the proper storage technology is a must for microgrids. You should select the right energy-storage technology based on expected cycle frequency and discharge depth.
High-power batteries are great for shallower discharge and high instantaneous power over many discharge cycles, while high-energy batteries have long charge and discharge times, as well as deep discharge depth. Whichever you decide to use, communicate with the client what you are using and why — the more your client is educated, the less chance there will be misunderstandings at the end.
Although this is hardly an exhaustive list of what it will take to make a commercial microgrid project a success, these three tips will put you on the right path.
