GTM has charted the rise and fall of more than 150 solar startups. A few failed magnificently, but most of the others just faded away -- victims of greed, sloth, pride or any of the other deadly sins of startups.Bloo Solar

falls into the latter category -- the one where investors don't perform adequate due diligence and the company goes forward with a technology based sheerly on collective self-deception. Sources close to the company claim that the startup is winding down and selling off its assets. We've reached out to CEO Larry Bawden for comment but have not yet received a response.

The startup originated with IP from UC Davis based on nanostructured silicon and later aimed at building nanostructured “bristles” with cadmium telluride as the PV absorber material. More recently, the company settled on amorphous silicon as the PV absorber.

Bloo claimed that "each bristle in the brush is an individual solar cell with a conductive core that converts and channels energy efficiently to a conductive backplane." According to Bloo, the technology's advantages over existing planar solar cells included more optical volume, better light trapping and minimized recombination by providing a long photon absorption path and a short carrier collection path.

Bloo also claimed that the energy yield of its cell could be "two to three times higher than current technologies." That claim would serve as a red flag to anyone with a bit of solar technology experience.

Bloo Solar's patent portfolio included "[m]ethods for forming nanostructures and photovoltaic cells implementing same," with an abstract citing "a photovoltaic nanostructure [that] includes an electrically conductive nanocable coupled to a first electrode, a second electrode extending along at least two sides of the nanocable, and a photovoltaically active p-n junction formed between the nanocable and the second electrode."

Acadia Woods Partners

was the main investor in Bloo, with about $20 million deployed over the last decade. Acadia Woods is helmed by Jeff Samberg, son of Art Samberg of Pequot Capital Management, at one time one of the world's larger hedge funds with over $15 billion under management. Art Samberg is also chairman of the board at Tri Alpha Energy, a fusion energy science project.

The "volumetric effect"?

I spoke with a half-dozen ex-employees of Bloo -- none wishing to be quoted or quoted with attribution. Some common themes emerged: frustration; wasteful spending; people were "misled" with "no path forward." There were tales of difficult firings, early employees in acrimonious relationships with management, an idiosyncratic physicist (in truth, more colorful adjectives were used), and an inept top leadership which was apparently unfamiliar with the laws of thermodynamics.

From a technological standpoint, the company had to shift from its early materials experiments with cadmium telluride to a more manufacturable "meta materials" platform depositing amorphous silicon on microimprinted polymer structures. Along the way, the company acquired an expensive cluster computer to perform computational modeling to determine whether the company's "belief" in a "novel" theory of light absorption on a 3-D structure, dubbed the "volumetric effect," was real.

Sources familiar with the firm said that there was improved "absorption of photons in the infrared band-edge on a 3-D structure compared to a similarly thick (or thin) planar absorber," but not the level of improvement that would lead to 2x or 3x gain in energy yield claimed by the company's leadership. Sources told GTM that the company's "volumetric effect" was not in accord with photonic theory.

Technologists that worked for the firm said the real value proposition for the company was not improved efficiency, but rather the ability to use thinner absorber layers by extending the photon absorption path length and decreasing the carrier collection distance.

Lessons learned?

So, is there anything to be learned from this disaster?

Almost all the Bloo sources spoke of the need for investors to do better vetting of technologies, consulting with credible solar industry experts. Sources regretted their own lack of vetting in taking jobs at the company.

This was deep science requiring fundamental research -- not the typical domain of venture investors. The startup was never able to attract any traditional venture capital, and when the one large investor lost interest, it was lights out.