If you need more proof that thin-film solar cells is where the action is going, take a look at the money flow.
SoloPower is raising almost $200 million to ramp up manufacturing of its thin-film solar cells, according to a report in VentureWire picked up by other media outlets.
A diagram showing SoloPower's roll-to-roll solar cell manufacturing process.
(Credit: SoloPower)The San Jose, Calif.-based company makes cells from CIGS, a combination of copper, indium, gallium, and selenide which a number of solar companies are betting can undercut traditional crystalline silicon.
Thin-film solar cells, from CIGS or other materials, are less efficient at converting sunlight to electricity but use far less material than silicon, making it potentially cheaper.
CIGS cells are also flexible, enabling things like solar rooftop shingles. At the same time, fabricating cells with that combination of materials has been fraught with technical challenges.
SoloPower's hefty funding is the latest to pour into thin-film CIGS solar start-ups.
NanoSolar last month disclosed that it has raised $300 million, bringing its total funding to about half a billion dollars.
Another thin-film start-up, Ava Solar, raised $104 million in equity last week to make cells from cadmium telluride like high-flier First Solar. CIGS maker Miasole is said to be seeking to raise an additional $200 million as well.
These relatively young companies are taking in a lot of money, when compared to companies specializing in things like smart grids. But to be competitive on cost, solar companies need to manufacture high volumes of cells, and building these facilities requires large capital investment.
SoloPower's technology is a roll-to-roll manufacturing process in which CIGS cells are layered on a flexible substrate. It layers the cells through electroplating, rather than sputtering, which is the technique used by hard-drive manufacturers to layer on magnetic material.
SoloPower's series B venture round in July of this year raised $30 million.
A recent report by Greentech Media and the Prometheus Institute forecast thin-film production to double in each of the next three years, with CIGS being the most "exciting yet elusive."
The study forecast that the thin-film cells will cost $1.40 per watt or less, with a 50 percent gross margin, while silicon cells manufacturers' margins could be as small as 15 percent.
Rommel Noufi, one of the primary experts in copper indium gallium selenide (CIGS) solar cells, is joining SoloPower as vice president of research.
Noufi has been a fixture in CIGS for several years as a scientist at the National Renewable Energy Laboratory. He also holds the record for efficiency for CIGS cells: one of his cells can convert 19.9 percent of the sun's energy into electricity while another can convert 16.5 percent. When reporters or analysts have CIGS questions, the path in the past several years has often led to Noufi.
Efficiency has been a major headache for CIGS vendors. These solar cells are not as efficient as silicon solar cells, though they cost less. Mass-produced CIGS cells are only at around 10 percent efficiency. To compete with silicon, efficiency needs to increase.
Nouri's record-setting cells have been produced through an evaporation process. The active ingredients are placed onto a sheet of glass or metal foil in a solution. The liquid solution is then evaporated, leaving a lattice of materials that can convert sunlight into electricity.
San Jose, Calif.-based SoloPower, among others, wants to make CIGS cells with different, faster processes. SoloPower said it can electroplate the active materials onto metal foils. Perfecting these new processes, however, has not been easy and many companies have had to delay production. Nanosolar, which prints CIGS cells, is the first non-evaporation CIGS company to enter commercial production. (Global Solar, which uses evaporation, is the only other CIGS company in commercial production.)
Venture capitalists have invested over $30 million in SoloPower, which plans to build its first factory in Silicon Valley.
- prev
- 1
- next
