Over the past decade we have thankfully seen an increasing interest in the effects that our fossil-fuel dependent economy and lifestyle is having on the environment. Everyone has likely seen or heard of “An Inconvenient Truth”, the documentary produced by Al Gore in which he provides overwhelming evidence in support of global warming. To what extent our current climate and the Earth’s ecosystem as a whole has been altered due to our industrious ways over the past 150 years or so is certainly up for debate. What’s not so debatable is whether or not this type of reliance on fossil-fuels is sustainable or even economically favorable in the years to come. With that in mind, why not tap into a source of energy that is constant and far more environment friendly, that is to say why not focus our efforts on using solar energy?
This idea is far more difficult to pull off than it is to suggest, solar panels and solar cells lack the efficiency and the power we’d like to hope for. Luckily researchers are making advances in a particular type of photovoltaic cell, thin-film cells, by using lasers to increase the efficiency of the electrical output. The two biggest issues that researchers need to address is how to manufacture solar cells more cheaply and how to increase the amount of solar energy they can convert into electrical energy. The cost element is reduced by using thin-film solar cells instead of the standard bulky cells. The efficiency element has been tackled by Yung Sing, a mechanical engineer and professor at Purdue University, who uses laser technology to his advantage.
Here’s how it works; Solar cells are connected by very small microchannels so that they can be interconnected in such a way to produce enough electrical energy for us to use as a power source. Normally these channels are made by a somewhat crude devise, a stylus, which scribes the channels into the film layer. But these channels are rough and imperfect. Shin uses a high-powered, ultrafast laser that fires in short pulses to create his channels which are much cleaner and precise due to their sharp edges which in turn increases the efficiency. This method also allows manufacturing of thin-film sheets with precise microchannels at a faster rate than the normal stylus method, two birds with one stone.
Shin’s work is funded by the NSF and with help from his grad-students and fellow researchers it is looking like we may be able to rely more and more on thin-film solar cells with laser-scribed microchannels in the near future. For more information on stories like this and how you can help support future researchers hoping to follow in Shin’s footsteps please visit us at http://massacademysciences.org/.
Written by: Matthew Panechelli