Organic solar cells are the next big thing in solar energy technology. Projects are still very much in the development phase but researchers from different institutions around the world have made significant advancements in combining organic and inorganic matter in the name of increased efficiency and lower production costs.

Let's summarise two of the projects currently underway in the US.

Researchers at Stanford University have determined that a single layer of organic molecules can triple the efficiency of a solar cell. The secret (which isn't really a secret any longer) lies in quantum dots. If you're anything like some of the characters in Terry Pratchett's Discworld books, you may think of quantum in vague terms that can be applied to anything very big or very small or very scientific. In this instance, quantum refers to something very, very small.

Clean Technica breaks this information down into more manageable pieces. Quantum dots are one nanometre small - that's one thousand-millionth of a metre if you're that way inclined. However, its incredible tininess gives it an almost limitless ability to absorb energy; in this case, solar energy. These dots were discovered in the early 1980s but have never really been properly explored until now.

The driving force behind the Stanford project is Stacey Bent, a professor of chemical engineering. She was interested in finding out whether quantum dots, which are made from simple chemical reactions, could increase the efficiency of solar technology while lowering costs. It turns out that they can.

It's possible to tweak or tune quantum dots to absorb a certain wavelength of light, which does interesting things to electrons with the knock-on effect making the inorganic (usually silicon) semiconductor more efficient. Bent is currently testing cadmium sulfide quantum dots, which she says aren't ideal for solar cells. But, she has plans to test others.

MIT (Massachusetts Institute of Technology) is looking at ways to create a solar cell that is self-sustaining. The inspiration comes from the photosynthesis processes used by plants, which Michael Strano believes can be replicated using organic solar cells. At its most basic, the theory has it that instead of being degraded or worn away by the sun, solar cells would be able to reassemble their molecules and maintain a consistent level of efficiency.

So far this theory is even more developmental than that of Bent and still needs plenty of work before it becomes something we can look forward to.

Whichever way you look at it, the organic seems destined to be combined with the inorganic to increase efficiency. As the Borg say, resistance is futile.

We write about solar heating for the highly experienced South African renewable energy supplier, Kayema Renewable Energy Solutions.

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