Doable Renewables: 16 Alternative Energy Projects for Young Scientists
ACKNOWLEDGMENTS wish to thank my wife Annelle Rigsby for catering to my time and space needs in the writing process Renee Zucker brot my agent has continued to support and believe in me Jerome Pohlen my editor has assisted not only in the writing process but also in moving gadgets around at the Maker Faire At the Maker Faire Marc de Vinck made me feel much more important than I really am My daughter Tia Rigsby volunteered to help with drawings and photography Ember and Forrest Tanksley would have volunteered to help but their wedding got in the way At work Fran Shahbazian and Lil Wagner politely listened to my daily progress reports Rob Phelan when he heard of my hurricane loss loaned me his old college textbooks Eyra Cash another engineer provided technical advice such as You're not going to use math and I'm an engineer and I don't understand
INTRODUCTION ears ago Bishop Milton Wright brought a rubber band powered helicopter to his sons Orville and Wilbur who were then 7 and 11 years old The Wright brothers later claimed that their interest in flight began with this gift Another child age 5 was sick in bed His father brought him a magnetic compass The boy could not get the compass to point in any direction but north There was something behind things something deeply hidden he observed The boy was Albert Ein stein The world can be changed turned upside down by a kid with an idea Perhaps even you This book is full of ideas about renewable energy for you to explore Renewable Energy As the world's population continues to grow an increasing num ber of people will gain access to lighting communication tran sit and computing This increasing demand will strain the Earth's resources We need renewable energy If humans cap tured one week's worth of sunlight striking the Earth the energy needs of the planet for one year could be met Thomas Edison once said T d put my money on the sun and solar energy What a source of power I hope we don't have to wait until oil and coal run out before we tackle that Wind blows your umbrella Sun warms the Earth Lightning strikes The tide comes in These forces all can be channeled into usable power Renewable energy is the silent hand behind these
events Renewable energy is generated from sources found in nature such as sunlight and wind It is renewable because it is not used up and will be available in the future The plans in this book allow you to construct and explore working models that generate renewable energy Most chapters include additional suggestions for creating science projects The projects employ several methods for converting energy into use ful forms Remember everything that moves makes noise warms up cools down or dries out requires the transfer of ener The plans in this book should be thought of as seeds they will get you out of the ground but they require innovation and work to grow into tall trees Most of these projects are in a sense solar powered They convert heat into motion or heat into electricity Because the cost of energy has been in the past relatively inexpensive many of the devices around us have not been designed with much attention to efficiency Wasted heat is common Refrigerators cool your food but warm the kitchen for example This may be good in the winter but in the summer your air conditioner must remove this extra heat from the house which expends more energy and costs you money You pay to heat the water in your shower but also to warm your drainpipe the water in the drain is almost as warm as the water coming from the showerhead so most of the energy is sent down the drain If you can find heat that is being thrown away and use it for a good purpose you will be making the world a better place With today's technology saving energy is more cost effective than generating clean alternatives so efficiency will be the focus of one chapter Thermodynamic limitations will be examined too For exam ple engineers will tell you You can't get something for noth ing and Low temperature heat engines are very inefficient That being said the energy that may be extracted overnight from 15 000 gallons of water a swimming pool can supply more
electricity than is required to light a house for the entire evening Many of these projects are primarily for demonstrating certain principles so they barely move but others clearly have the potential to be scaled into real world practice Sunlight concen trated on solar cells produces electricity while also producing excess heat Rather than being a wasted by product this heat can be piped off to a heat engine to increase the efficiency of the solar energy conversion The human powered light system aside from providing good exercise can be useful in locations where there is no electricity It also demonstrates the use of efficient lighting LED lamps and the future of electrical storage ultracapacitors Unlike bat teries ultracapacitors can withstand hundreds of thousands of charge discharge cycles so they rarely need replacement Safety First If you work with energy you need to be careful Humans are del icate creatures and small amounts of energy can cause problems To be injured by the sun all you have to do is stand in it too long and you risk a nasty burn And if you concentrate sunlight it is easy to burn things such as solar cells Melted plastic on my solar
