Our book today, Doable Renewables:Â 16 Alternative Energy Projects for Young Scientists by Mike Rigsby, is full of creative new ideas and information. Do you remember in our post about smart materials (the materials that respond to the environment), we were looking for a source of nitinol (nickel-titanium alloy) wire? This book not only lists a source, but also uses nitinol springs in projects. 
Mike Rigsby is a professional electrical engineer and he has a noble cause for writing this book. He has come up with projects to investigate various forms of renewable energy in the hope at least one of them will spark a young person to discover something that will change the world. His projects include making engines that use heat as a source of energy (including one with nitinol springs), solar energy, wind energy and wave energy. Each project is explained clearly, with a detailed list of supplies and numerous black and white photographs showing the assembly, as well as the finished project.
Before we get too excited, though, let’s do the reality check. Safety is one concern. Some of these projects have steps that could potentially cause injuries, especially those that involve cutting. Unlike many of the activities found in children’s science books, some of these projects are not made from items lying around the house. Many will require the purchase of specialized pieces of equipment or supplies from science and technology suppliers. For example, the nitinol springs are available from Jameco Electronics, part number 357835. As of today, they cost $45.95 for a 4 pack. The bottom line is that this book is for serious older children or young adults who enjoy engineering and inventing, and who preferably have an experienced adult mentor.
That said, do you have a science fair coming up soon? Doable Renewables: 16 Alternative Energy Projects for Young Scientists is a wonderful resource sure to generate innovative science fair projects.
In fact, the book inspired us to do some of our own investigations:
1. Stirling tin can engine
In chapter 4, Mike Rigsby suggests purchasing a Stirling engine to explore this technology investigated by Reverend Dr. Robert Stirling way back in 1816 (see our Amazon suggestions below). The Stirling engine uses heat to do work, and is known to be very quiet in comparison to the internal combustion engine.
Rigsby also mentions that there are instructions for building your own on the Internet, so of course we had to look. We found quite a few examples of Stirling engines you can make at home plus numerous videos of the engines in action. Here is one example of a fan Stirling engine (note: there is a pop-up ad).
The instructions can be found at Easy to build Stirling engine
There is more about how Stirling engines work at How Stuff Works.
2. Radiometer 
We already had a radiometer, so we dusted it off and tried it out. A radiometer is a glass bulb that looks like a light bulb. Inside are 4 tabs suspended from wires. Those tabs are reflective on one side and black on the other. When placed in sunlight, the tabs rotate like crazy.
The Crookes radiometer caused quite a stir in its time, because no one was quite sure how it worked. Several hypotheses were proposed and shot down. Eventually the idea of thermal transpiration was found to be the one most generally accepted. It involves the movement of gases from the warmer side of the tab (the black side) to the cooler, reflective side. In any case, the only energy supplied is that from the sun.
3. We have a previous post on Windmills and wind power that also relates to this topic.
We hope this inspires you to try a few new projects with renewable energy. Be sure to let us know how they turn out.
Reading level: Ages 9-12 (Amazon)
Paperback: 224 pages
Publisher: Chicago Review Press; Original edition (October 1, 2010)
ISBN-10: 1569763437
ISBN-13: 978-1569763438
This book was provided for review.
Stirling Engines at Amazon
Other scientific supplies suggested in the book:
