Walked one of our sites this week—we did planning, feasibility, design, and proposed on the construction of a 540kW array on the top of a parking structure in Silicon Valley.  Solar over parking garages is a win-win-win.  It enhances property values, doesn’t take away parking, and the way we designed it, it became an architectural touchstone for the entire project, setting a new standard for corporate facilities.

The steel structure looked great—with a camber built into the beams, the proportions felt right and the design was complementary to the parking structure—not an easy move to pull off.

We expect this system to meet roughly ten percent of the adjacent office building’s demand, and with the lease financing we proposed, it was cash flow positive for the first five years, and you own it after ten [with a small buyout].

I was reminded that design is only as good as the execution—and PV is a game of inches—we fight for every percentage point of performance.  We believe module mismatch losses are avoidable—you are building a thirty year system—and throwing away a couple of percentage points of yield just because you don’t have time to sort modules by performance is baffling to me.  In the end, systems deliver a yield, and it seems unwise not to practice the same care in construction that we did in developing the system.

Grounding is an essential, but poorly understood, component of system design.  “Lugless” grounding design is a great concept, but ground faults are such a danger that you need to be sure that no shock hazard exists in module frames, metal structures or enclosures.  Installation should proceed as if everything conductive is at lethal potential to ground—until a megger or multi-meter proves otherwise.

It’s all in the details.