French Gerleman


St. Louis, Missouri


Grid-interactive technology test-bed of multiple roof-top solar-PV technology configurations


70,000 kWh

Estimated Annual Production:

We developed, engineered, and managed the construction of a rooftop demonstration project for French Gerleman, a regional electrical distributor. French wanted to establish a test bed for their clientele, to showcase products and become expert in the performance and applications of product technology.

Design Rationale and System Architecture: The power electronics have two points of common connection, one on the 208 V side of the building and the other at a 480 V point of common coupling. There are parts of the array that are identical except for part having DC-DC optimizers or not, parts with different string inverters, different racking, different tilt, different module cell types, and different back sheet colors. There are four different monitoring systems installed, to provide knowledge on how those systems compare and perform over time.

The primary reason for the complex and varied system architecture was to provide a technology and climate test bed that the client could use to establish its position as a market thought leader. The project was effective in doing this, and has provided much comparative data on snow impacts, hot weather, and different system design elements.


Project Challenges: The greatest challenge to this project was integrating the extreme range of technologies and wire management products, operating at two different system voltages, into a design package that could be effectively bid by, and communicated to, the electrical contractor. This requires a concise and clear set of Construction Drawings that still communicated the very diverse requirements of the project.