DALLAS --- Reporting from Solar Power International.

A few years ago, I asked Dick Swanson, the founder of SunPower, about his opinion of module-level electronics and microinverters. Swanson is too much a class act to bad-mouth fellow solar aspirants and entrepreneurs -- but he did not seem too impressed with the entire class of distributed electronics.

Fast-forward to a few years later. SunPower (Nasdaq: SPWRA, SPWRB) just announced their AC solar panels at Solar Power International in Dallas today. Their partner: Austin, Texas-based SolarBridge, a startup funded by VCs including Battery Ventures and others. SunPower is the market share leader in the U.S. residential market.

Last week Greentech Media broke the news that Canadian Solar had aligned with solar electronics maker, ArrayPower, another VC-funded upstart. The CEO of ArrayPower, Wendy Arienzo, called the device a "sequenced inverter" in a recent interview and is directing it at commercial-scale applications using crystalline silicon modules.

As for AC modules, here's a comment from a colleague, "An AC module is as good as the microinverter it is attached to. Any module vendor that attaches an unproven technology to their modules is potentially risking their reputation, especially in an environment where there is so much focus on the industry to not trip up."

As with all distributed electronics schemes, these technology solutions seek to maximize energy harvest, minimize power attenuation from shading and panel or thermal mismatch, and improve on the reliability and efficiency of central solar inverters, the long-dominant technology.

So the microinverter firms are busy allying with the panel manufacturers, getting to market in tandem with the big players and with a big-player guarantee. SunPower's AC panels are backed by a single, end-to-end 25-year warranty.

On the other hand. Enphase, the microinverter pioneer fresh off of shipping its millionth unit, has taken a different route to market -- selling through distributors, installers, and integrators. And my understanding is that Enphase does not exactly have a sunny relationship with SunPower.

Enphase has the clear early lead, but they have a lot of folks on their tail.

Lots more balance-of-system and inverter news to come this week from Dallas. Stay tuned.

Tags: ac modules, acm, arraypower, balance of system, bos, canadian solar, distributed electronics, enphase, solar electronics, solarbridge, solarpower international, spi, sunpower