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You can't trundle around the Solar Power International exhibit halls (or the offsite meeting rooms) for long before you stumble across innovation. Materials innovation, production equipment innovation, cell innovation, module innovation, inverter innovation, system innovation--there's more innovation than you can shake the proverbial stick at. Some of the innovation is evolutionary (purer polysilicon, thinner wafers, mondo-sized thin-film glass modules), while other approaches come closer to reaching the high bar of being revolutionary (flexible or tubular CIGS modules, organic PV, solar-powered killer nanorobots...).

One of the latest examples of solar innovation engine horsepower that has attracted great interest on the show floor comes in the form of a relatively small but mighty box--the Enphase Energy microinverter.

I had to battle through the throng surrounding the Enphase booth, then wait for Raghu Belur to finish with a steady stream of potential customers and the persistently curious before we could talk about the company's intriguing microinverter system. Instead of one medium-sized or big inverter box--or several boxes--serving a PV power system, Enphase has devised a smart one-inverter-per-module approach that has the potential to really shake things up in the way integrators look at how they put their systems together.

Belur, VP of marketing and cofounder of the venture-backed company, explained how these simple-to-install little boxes redefine maximum point power tracking, greatly enhance the photonic energy harvested to the tune of 5%-25%, boost system reliability, and make life easier for the those who design, install, and manage solar-PV power systems (since there's no need for high-voltage DC wiring when using the Enphase units, for example).

One semiobvious advantage of this more modular inverter is that it eliminates the single point of system failure that traditional boxes suffer from, according to Belur. If an Enphase minibox goes down, only the module where it lives is affected--although to hear the cofounder tell it, such failure would be highly unlikely, given its sturdy custom ASIC architecture and mean-time-between-failure spec of a mere 119 years.

The micros' parallel modularity also means no more "Christmas tree effect" in a solar-panel array (sorry, Mr. Grinch), where one module goes down and takes the rest of its string with it, Belur points out. If there are modules suffering in the shade, the rest of the system will keep on pumping electrons through. In some cases with big systems, a string of modules could go down and no one would know, something that the microinverter strategem avoids.

Which leads to another compelling piece of the Enphase story: the Enlighten per-module monitoring and analysis tool. The Web-enabled, real-time platform garners a variety of data specific to each module, such as temperature, voltage, current, power, and energy. System-level installation info and a schematic view of the array can also be visualized in the view pane. The info is transmitted from the PV system first over the powerline, then converted through a communications gateway and sent via broadband connection to the server.

Of course, data are just noise unless you do something with them, so the signal comes through in the tool's ability to analyze production glitches, looking for the cause of said glitches, and offering solutions to get the module or system back to maximizing electrons out.

Since a costly solution is no solution at all when it comes to the pursuit of solar's grid-parity grail, Belur showed me a 250-KW system analysis that found the Enphase microinverters match up or beat the cost of traditional inverters, with even better comparison on the operational expenses side.

The 95%-ish peak efficiency microinverters are currently offered in two flavors for 24- and 32-V modules, but there will be more models as the product line rolls out. The little boxes are PV technology agnostic--crystalline silicon- and thin film-based, trad glass or flexible substrate modules can all benefit.

Belur says they've shipped several thousand microinverters under warranty so far, but it's likely just the first few decibels of what should become a deafening roar. "We've seen BIG interest, it's going to be insane," he sighs with a smile.

That's the kind of crazy most start-ups would be happy to live with.