Solaria has received $45 million in additional funding from new and previous investors to show that concentrators have a future.

The company has created a solar module that emphasizes less silicon. It starts with a regular module. The cells are then "singulated" into strips to produce a module that sort of looks like shredded wheat: half of the cells are removed and put on another module. An optical concentrator that effectively doubles the amount of sun striking the module is added. The process results in a solar module that requires less raw material but puts out the same, or more, power as a conventional module.

Solaria sells its modules to utilities and independent power providers for large-scale solar parks. The modules are placed on trackers. Dan Shugar, who served as president of tracker specialist PowerLight during its rapid rise, became CEO earlier this year. (SunPower ultimately bought PowerLight.)

So you've got money, an interesting technology, a customer base ravenous for solar and a way to save silicon. What could go wrong?

Silicon prices. When the company was founded, silicon prices were climbing. Silicon prices have come down from their highs and some nations (China) are studying ways to restrict polysilicon production to help existing manufacturers.

"Replacing half the silicon with a potentially expensive, time-consuming, and low-yield process made only a little sense when silicon was expensive.  By all accounts, the price of silicon is forecast to continue to fall and that just erodes Solaria's value proposition.  The  metrics that matter are dollars per watt, dollars per watt of capex, and efficiency," my colleague Eric Wesoff wrote in January.

Concentrators also continue to remain a zero-billion-dollar market.

On the other hand, concentrator outfits do seem to be honing in on their target markets better. Soliant, for instance, is targeting large, flat roofs in Southwest-like climates only. This laser-like tailoring of a solution to a customer might work: it allowed a workstation market to exist for a good ten years. Solaria has refined its message and target customer base, as well, and one of the company's newest investors is Mitsui, a strategic partner with lots of projects worldwide.

So stay tuned.

A few other notes:

General Compression, which wants to put compressed air in an elaboratestoragecontainer as a form of energy storage (think industrial-sized whoopee cushions), has raised $3 million more, in addition to the $20.9 million raised in previous efforts. The company is building a system with ConocoPhilips that could go live next year.

Finally, Bob Stempel, the former CEO of GM who helped usher in the doomed EV1, has joined the board of Envia, a lithium-ion battery maker. Prior to working for GM, Bob served as CEO of Energy Conversion Devices. Both GM and Energy Conversion have endured major, chronic financial losses.