Two-faced solar cells are probably better than one

Engineers have long known that a double-sided solar cell design would increase cells' overall harnessing power. The main barrier to creating such a double-cells was an economic one. However, one solar startup claims they have figured out a way to tweak the production process to make "bifacial" designs economically feasible.

While the majority of the energy for a double-sided cell would still come from the plane directly facing the sun, there are still light waves that manage to bounce into the underside of the cells. The traditional process of manufacturing two cells wouldn't be worth the small (but not insignificant) extra energy that could be harnessed.

By changing-up two cell ingredients, Jerusalem-based bSolar says they have come up with an economically-viable two celled design. The first step is to utilize cheaper boron instead of platinum when creating the back-surface field. The second step is to replace conventional multicrystalline silicon with more expensive (but far more efficient) monocrystalline silicon crystal wafers.

The resulting tweaks can harness anywhere between 10 to 30% more energy for conventional mounted inclined panels and 30 to 50% more for vertically mounted panels.


An illustration of how solar energy can be harnessed on two sides of a cell

The cells are best utilized against surface that is coated in a reflective white or silver, or by facing existing reflective surfaces such as a vent or outdoor AC unit.

The firm has already landed a major deal with Nasukarasuyama City in Japan to use the bifacial cells in the city's huge ground-mounted project.

Sometimes being two-faced is a good thing.

via GizMag, via bSolar