Super-Efficient Tandem Solar Cells
Natcore's scientists have discovered that its LPD process could allow, for the first time, mass manufacturing of super-efficient (30%+) tandem solar cells. For comparison purposes, these cells could achieve twice the power output of today's most efficient solar cells.
Until now, these tandem cells have been producible only by using very special, expensive semiconductor materials, and at very high costs. Natcore's process has the potential to allow tandem cell mass production at a lower cost/watt than anything available today.
For reference, review the accompanying schematic of a third-generation, silicon-quantum dot tandem solar cell.
Natcore envisions its LPD process allowing the manufacture of a tandem cell consisting of up to three cells arranged one on top the other, starting with an ordinary silicon solar cell on the bottom.
Something called a cell interconnect comes next, then a second cell made of silicon quantum dots. This solar cell is tuned to absorb light in the middle of the spectrum, represented in the picture by the green color.
A second cell interconnect follows and a third cell, another silicon quantum dot device, sits on top. This uppermost cell is tuned to absorb the blue end of the spectrum.
The combination of all three operating in tandem would produce over 35% efficiency - or about double the output of current technology.
Natcore's edge in this process is the ability to embed the two types of silicon quantum dots in the two cells within a layer of silicon dioxide using our liquid-phase film growth process. All current and recent attempts to create viable tandem cells have used vacuum deposition techniques that are expensive and do not allow independent control over the formation of the quantum dots and the way they are arranged. That is a major disadvantage.
In fact, Natcore's LPD process is what makes it possible to even consider producing a tandem cell on a commercial scale, let alone in the lab. Not only that, the full device can also utilize our proprietary AR coating deposition process, thereby realizing additional production cost savings.
Through the combination of these two applications, Natcore hopes to bridge the economic gap between solar power and conventional energy production - an achievement that represents the "Holy Grail" of the alternative energy industry.