PV Gap

Barry Said:

what is the sunlight-to-electrical conversion efficiency of the solar cell?

We Answered:

Depending on the type of solar panel, they are anywhere from 8% - 22% efficient. CIGS have low efficiency, but can be flexible for multiple applications. Mono and poly crystalline can be in the mid teens and generally the most affordable, and some hybrid solar panels are up in the low 20's, but you pay a premium for them.

Anthony Said:

How long until Solar cells can achieve 80% efficiency?

We Answered:

Conventional silicon cells have a theoretical limit at about 30%, depending on who you talk to.

Exotic, multilayer cells have gotten into the low 40-something percent efficiencies.

I've heard rumors of a theoretical efficiency of 80% for some quantum-type cells, but right now, that kind of design is no better than about 3%. There is no timeline that I've seen for beating conventional cells.

An 80% solar cell is exciting, but I'm sure that same dream of unlimited applications was held out for 40%. What is important is the cost efficiency, dollars per watt, not the conversion efficiency, watts per square meter. If there was an 80% efficient panel, but it was $5 million per square meter, that panel would still be restriced to space and military applications. On the other hand, if there was a panel that was 8% efficient, but 10 cents a watt, everybody would have them.

Betty Said:

How many solar cells could be solder in a series ,without effecting their efficiency considering shunt resista

We Answered:

For a series connection of PV cells, the resistance rises in direct proportion to the voltage while the current remains constant; the resistive voltage drop is directly proportional to the number of cells.  This means the efficiency remains constant regardless of how many cells are connected.