In the spectacularly high-growth $20 billion dollar global solar market, CPV is a zero billion-dollar market segment with only a few megawatts deployed, stuck in the middle between the rapidly commodifying silicon solar market and the well-financed high-output concentrated solar thermal market.

Concentrated Photovoltaic Technology (CPV) has received more than $350 million in venture capital funding since 2005, tens of millions from the Department of Energy (DOE), and tens of millions from public markets to fund development of this promising solar technology. But to a great extent, CPV has been overshadowed by other solar sciences, notably concentrated solar power (CST or solar thermal), thin-film solar and wafered silicon (the current dominant technology).

The fundamental concept behind CPV is the use of a very high efficiency solar cell that is much smaller than the optical collection area. The value is that "cheap" glass and metal replace expensive (?) and capacity-constrained (?) silicon and provide a super high-efficiency module. GaAs triple-junction III/V solar cells (with >35% efficiency) result in a higher power density, a more efficient use of land, and a potentially lower Levelized Cost of Energy (LCOE).

Check out Part OnePart Two and Part Three at Greentech Media's Green Light blog