This week's cartoon describes Concentrated Solar Power, a specific method of collecting energy from the sun using trough-shaped reflectors. Here at Worldchanging, we've covered the potential of parabolic solar solutions from various angles, including the recent article Clean Power from Deserts, and Rob Katz's 2006 post, DIY Solar Solutions for the Developing World.
Editor's note: This post is part of a series featuring Worldchanging ally Andy Lubershane's original graphics. While many of the issues covered in the comics have been discussed on Worldchanging in the past, we hope that you'll be able to use this new medium in a different way … whether it's in your classroom, on your office wall, or to help explain ideas to friends and family.
Andy Lubershane researches, writes and cartoons about sustainability from his home in Boston. He can be reached at alubershane[at]gmail[dot]com.
I really enjoy these "earthly ideas" and love the animations and witty asides.
I do have one quibble with this one.
In the depiction of the parabolic trough, a key point of the geometry is that all the light is coming from the sun, which is a very long way away, and therefore all of the rays of light should be (essentially) parallel. As drawn it makes it look like the trough is somewhere inside the radius of the planet Mercury.
There are other solar thermal systems (such as those for heating water for swimming pools) that are able to take advantage of diffuse light, but without the dramatic temperatures of concentrating systems. Because of the need to focus the light, concentrating systems must have some kind of active sun tracking component, a heliostat.
Thanks again for these great comics.
Jeff, I'm glad you like the comics! Good point on the solar rays coming into the dish...I'll have to edit that in future versions if they occur. Thanks!