Load Profiles: How different storage systems, microgrid controllers fit specific C&I sites

By: Chris Crowell

See the full article on Solar Builder's website.

‍Industrial Warehouse

‍Sandbar Electric warehouseLoad profile: When setting out to build its new corporate headquarters, Santa Cruz-based solar installer Sandbar Solar & Electric had a choice: Plan and pay for the costly, multi-year process of connecting to utility power, or equip the building to run independently from the grid. Interconnection to the local utility was estimated to cost around $75,000 and take 18 months to complete. Once connected, Sandbar Solar & Electric was looking at an average monthly electricity bill of about $1,000.Goal: Operate the Sandbar Solar & Electric headquarters independently from the utility grid and champion innovative renewable energy technologies.

‍Solution: Microgrid

‍• Battery system: Two Blue Ion LX cabinets, 64-kWh capacity total, three Avalon 30-kWh FB3

• Power conversion: Two 30-kW Ideal Power 30C3 inverters, one SEL-547 protective relay

• Solar: one 38-kW array, one 21-kW array• Generator: 50-kW Blue Star natural gas generator with Basler controller

• Controller: Ageto Energy ARC

By adding a Blue Planet Energy Blue Ion LX system, Sandbar Solar & Electric was able to increase their load capacity by 64 kWh, as well as benefit from increased efficiency and usefulness from their existing solar resources, while reducing reliance on the gas generator. With a highly efficient charge and discharge rate, Blue Planet Energy’s battery remains charged without expelling energy, allowing it to store 100 percent of the incoming solar energy and greatly reduce generator usage — and its associated environmental impact and noise. And, as the building’s energy needs continue to expand, the Blue Ion LX is fully scalable to 2+ MWh, allowing Sandbar Solar & Electric to easily install additional capacity to the existing system.

Combining all the elements listed above (minus the generator), Sandbar Solar & Electric’s system was designed to produce enough energy to satisfy the building’s energy needs for 96.5 percent of the year. The natural gas generator runs the other 3.5 percent of the time (about 300 hours total). The Sandbar HQ has commercial-grade, 480V, 3-phase power and has remained fully operational through all grid power outages that have affected its local area since the building’s completion in December 2019.

‍Lifetime savings: Over a 20-year period — not including the $75,000 interconnection study or the carrying costs for every month Sandbar Solar & Electric would have waited for grid connection — utility power would end up costing about the same as a microgrid over the lifetime of the system.