Wednesday, 22 December 2010

Solar Panels just took a big jump in efficiency

It has been a long hard slog to develop and produce solar panels with an efficiency rating of 25% (that is they convert 25% of the convertible light spectrum into electricity with the rest wasted). The original solar panels from the early 1970s had an efficiency rating of just 10%. So it has taken us forty years to just more than double the efficiency. I'm thinking that surely we can do better than that?

Other technology has been used to lesser or greater degrees of efficiency such as focussed lens solar panels, but these are far more expensive than standard solar panels and since regular solar panels to start with are 2X-3X as expensive today as the most expensive electricity in the United States, we don't need anything that adds to the cost.

One of the issues at hand is standard solar panels have two major drawbacks. The first is that they must be angled correctly or the angle of the sunlight will just bounce off the junction in the solar cell, with the potential to convert the light to electricity lost. The second drawback is that standard solar panels are able to utilize only a small and fixed portion of the solar spectrum.

These two factors may be about to change with the invention of an entirely new class of solar panels at the US Department of Energy's Idaho National Laboratory in Idaho Falls. The new panels are able to use a much wider spectrum of light than standard panels and additionally they are capable of absorbing energy at a variety of angles.
This leads to an efficiency of greater than 45% compared to the current best of 25% for the most expensive panels currently on the market.

The most interesting and salient point, however isn't the ability to use angles, it's the fact that in addition to being able to use a much wider spectrum of light, they are also able to use non-visible light such as infrared.

Why is that important?

Firstly greater than 50 percent of sunlight is in the infrared and secondly another name for infrared is *heat*.

What are the implications of that?

These solar panels can be used at *night*!

No comments: