Solexel used this week’s Intersolar to finally unstealth.
The 70-employee firm has revealed its innovative thin-silicon technology and looks to ship 20-percent-efficient photovoltaic modules at a cost of $0.42 per watt in 2014.
It’s the same solar startup story of high efficiency, low costs and low capex that has been pitched dozens of times to every cleantech VC or journalist since 2005. No firm has yet to execute on its promises at commercial scale.
Perhaps Solexel is the company that can bring those claims to reality. If the firm can’t, it won’t be for lack of innovation or funding.
On the funding front, Solexel raised $113 million in its first two venture capital rounds and is in the midst of closing a $37 million round C. Investors include Kleiner Perkins, Technology Partners, Northgate Capital, DAG Ventures, GSV Capital, Spirox, Gentry Venture Partners, Oak Hill Investment Management, Ecofin, and The Westly Group. In its most recent round, the firm added SunPower as an investor, giving it at least one backer that actually knows a bit about solar technology. And one that shares some common technological traits with Solexel: high-efficiency cell performance and a back-contact cell architecture. Surviving due-diligence with SunPower speaks well of the startup’s technology and path.
Solexel has also scored $17 million in DOE and NSF grants.
On the technological front, Solexel is looking to mass produce 35 micron-thick, high-performance, low-cost mono-crystalline solar cells using a lift-off technology based on a reusable template and a porous silicon substrate. The process ensures that the thin silicon is always supported during handling and processing while the back contact, p-type cell dispenses with the need for expensive silver – using aluminum instead. The process uses no wet steps according to the CEO, Michael Wingert, a seasoned executive from the hard-disk drive industry. The process employs CVD on trichlorosilene gas at atmospheric pressure with silicon deposited at a rate of 2.5 microns per minute. The cell uses almost ten times less silicon than conventional c-Si cells at about 0.5 grams per watt.
Mehrdad Moslehi, the CTO and founder of the firm, explained that at 156mm x 156mm, Solexel produces the largest back-contact cell in the industry. The firm will use a contract manufacturer to construct the modules, which will be available in frameless as well as framed versions. The firm’s flexible cells do not need the support of a frame. In fact, the firm’s cells don’t need the support of glass, and it envisions flexible, non-glass sandwich panels in future product offerings.