Enphase Planning to Embed Inverters Directly Into Solar Panel

A growing number of companies are working on technologies to squeeze as much juice as possible from solar panels and reduce the cost of these systems over their lifetime. One of those companies, Enphase Energy, now tells us that it is working on the next frontier of this development: It wants to embed its microinverters directly into solar modules so that the two are sold bundled to installers. Raghu Belur, co-founder and VP of marketing for the Petaluma, Calif.-based startup, said in an interview that the company is in talks with yet-to-be-named “global panel makers” and that in five years, he expects most of the company’s microinverters to be sold pre-installed. That will mean that “you have no notion of an inverter to install,” and will lead to savings through lower system and labor costs, he said.

The vast majority of solar installations today use a large, central inverter to convert the direct current (DC) flowing out of panels into the alternating current (AC) used by the electric grid. The inverters also have electronics, called a Maximum Power Point Tracker, that run algorithms to maximize the amount of power drawn from the panels. But placing these critical functions into one device has drawbacks: It means a failure of that one device takes down the whole system, and the weakest panel in the array eliminates the benefits of better-performing panels.

A host of companies are developing technologies that would distribute these functions to each panel. Most say their technologies will increase the amount of power that arrays produce by between 5 percent and 25 percent. Enphase is arguably in the lead, having already shipped “tens of thousands” of its microinverters. The microinverters today are mounted to the panel racks out in the field. The startup has deals with solar installer Akeena Solar and module maker Suntech Power. Enphase’s current deal with Suntech is for the module maker to directly market the microinverters with its products and not to embed the products into its panels. But while Belur wouldn’t specify which module makers the company was talking with for the embed, Suntech could be one of them.

While Enphase is leading in terms of market traction, it may not be the first to sell a microinverter embedded in a panel. The first could be Austin, Texas-based SolarBridge Technologies, which says it expects to be shipping its products with modules by the first quarter of 2010. The company said it is negotiating deals with global panel makers but would not disclose any names. SolarBridge might have the advantage on the embed front, because it has designed its microinverters from the start to be part of modules. (For more details on the difference between these two startups, check out this piece.)

Other companies working on microinverter technology include Menlo Park, Calif.-based Accurate Solar Power and South Plainfield, N.J.-based Petra Solar. But Enphase’s vision to embed its technology directly at the panel factory shows the startup is serious about maintaining its first-mover advantage. These other companies, however, will be nipping at its heals.