Coming to a seashore near you: Clean waterways using the sun!

Photo courtesy Andrew David Thaler

Check out this technology! There are at least one billion tons of plastic in the ocean. Wouldn't it be great to be able to collect this plastic before it gets to the ocean and is more difficult to clean up?

This solar-powered water wheel may be used to clean debris from water and can transfer this debris to a barge. Check out this site for more information!

P.S.: I just came across this video. It's good for a laugh.

What is a semiconductor?

"Monokristalines Silizium für die Waferherstellung". Licensed under Creative Commons Attribution-Share Alike 3.0 via Wikimedia Commons

A semiconductor is a material that typically conducts electricity better than an insulator, but not as good as a metal. Electrons in the material can move around, but, in order to move around, they must overcome an energy barrier. Things at higher temperatures have more energy. Some electrons in a semiconductor are able to overcome the energy barrier (between what are known as the valence and conduction bands) and move. Dopants (other added elements) can be added to the material to change the electron concentration. Places where an electron is absent but is of low enough energy that an electron "should" be there are known as holes. It is these mobile electrons and mobile holes (absences of electrons) that conduct electricity. Semiconductors are widely used to make solar cells as well as computer chips. They are extremely useful materials.

TED talks solar

Check out these interesting TED talks on solar power!

1. Donald Sadoway, Professor of Materials Chemistry at MIT


2. Sanjit 'Bunker' Roy, founder of Barefoot College


3. Bill Gross, founder of Idealab


Recommended by Community Renewable Energy.

Light Up Nigeria!

Check out this video about what solar energy has been able to do in Nigeria!

Move over for solar!

Credit: AAP

While solar energy still has far to come, it has surpassed many milestones over the past few years to the point that it is becoming competitive with other energy sources in some locations. Check out this recent article about rooftop solar energy contributions to the grid in Australia. Rooftop solar even drove the wholesale price of electricity into negative territory and to around zero during the day for several days. It will be interesting to see how solar energy will play out in the future. Will this make coal plants less profitable and drive them out of business? What happens then when the sun isn't shining brightly? How is the energy stored? Is the rooftop model the best for consumers? For how long will those producing energy with rooftop panels be able to charge retail price for the energy instead of wholesale price? How will the utilities respond? This is another article that deals with some of this response question.

Happy 4th of July!

It's the 4th of July and perhaps a good time to fresh up your potassium nitrate knowledge?!

That's, at least, what NSF thinks and hence, nominates potassium nitrate to the crystal of the week!

The crystal-of-the-week initiative is a celebration of the International Year of Crystallography which is THIS year!