Video on CleanTech

Here’s a video that presents four different cleantech concepts, with an interesting mix of validity.

The first, covering city streets with a reflective white coating, is completely valid, as it causes a significant percentage of the incoming solar radiation to be reflected back into space, rather than being absorbed into the planet’s surface.  As such, it’s a wonderful efficiency solution, lowering the costs of air-conditioning that would otherwise be required in these urban “heat islands.”

The second and third are devices that collect trash from bodies of water.  Here, the validity of the device is a function of the size of the pond, lake, harbor, bay, or ocean under discussion, and the density of the pollution in it.  While I’m not an expert in any of many ways to collect and remove refuse, I become immediately skeptical when I run across even the tiniest piece of BS.  Here, one of these devices are claimed it run on “water power,” which is clearly untrue.  Water doesn’t have any energy.  Water that has been lifted against the force of gravity has potential energy, and water that is motion due to some external force, e.g., falling downhill, has kinetic energy.  But neither is the case here.

The fourth is a huge piece of equipment that removes CO2 from the atmosphere, which I’ve seen and written about before. Since there are only about 400 parts per million of CO2 in the atmosphere, it’s couldn’t possibly be feasible to build and operate this enormous machine, which has its own energy footprint.  Bullcrap with a capital B.