Hybrid Solar Cell Hits High Efficiency

Startup Silevo has begun producing its efficient solar cells using commercial equipment, a key step toward commercializing a novel type of solar cell at large scale. 

The Fremont, California-based company today announced that its factory in Hangzhou, China next month will be producing at a rate of 32 megawatts per year. Having manufactured at that scale, Silevo now intends to raise private equity to build a 230-megawatt factory next year, says Chris Beitel, Silevo’s vice president of marketing and business development.

The company, which operates in the same city where failed solar company Solyndra was based, remains a survivor in the very challenging solar industry where even sophisticated and well capitalized manufacturers are struggling financially. (See, Once-Mighty Suntech Struggles to Survive and The Dog Days of Solar). 

Silevo was able to produce cells that convert 21 percent of sunlight to electrical energy, which is at the high end of commercial solar panels now on the market. “We’ve been able to successfully transition from research and development production (in California) to production-based equipment with high throughput,” says Beitel.

The company calls its Triex solar cell a hybrid because it uses different techniques to improve price and performance. A monocrystalline solar wafer forms the substrate and then machines add a thin-film “tunnel oxide” layer which results in better conversion efficiency in high heat than traditional silicon cells. Another layer of amorphous silicon allows for higher voltage to improve power production. And to reduce costs, each cell uses copper, rather than silver, wiring as traditional cells do.

Rather than design its own equipment, the machines to make Silevo’s cells and panels are modified equipment already used the solar and flat panel display industries. Using off-the-shelf equipment lowers the risk and will allow it to scale up more predictably, Beitel says. 

The cost of production at the pilot plant is expected to be 98 cents a watt, in the range of of large Chinese solar manufacturers. But Silevo expects it can command a higher price because of the higher efficiency and energy output. Beitel says the company has signed contracts or letters of intent with customers that represent 250 megawatts worth of orders.

The company’s plan is to build its larger, 230-megawatt plant to begin operation at the end of 2013. The cost of production at that scale will be between 70 cents and 80 cents per watt. At a full-size plant, Beitel projects its process can eventually reach 61 cents per watt. 

To finance this larger plant, the company is looking at an investment from private equity companies or a strategic investment, such as a joint venture with a larger company in the solar supply chain. So far, it has raised two rounds totaling $75 million from Asia-oriented venture capital funds.

The company intends to make two lines of solar panels—one aimed at residential rooftop systems and a larger, 305-watt panel for utilities.