Doable Renewables: 16 Alternative Energy Projects for Young Scientists
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
When you cut tin cans you are left with sharp edges Based on my painful experience do not place your hand inside a tin can for any reason Drilling sawing cutting soldering sanding and painting all involve some risk ALWAYS WEAR PROTECTIVE GOG GLES Never look at concentrated sunlight If you don't know how to safely do something find knowledgeable help Take your time and don't work when you are tired or
SIMPLE HEAT ENGINE n this chapter you learn to create a device that will turn heat into motion MATERIALS AND TOOLS Corrugated cardboard Y inch thick Scissors Glue Sewing needle 18 inches long 4 rubber bands 7 inches long and 1 16 inch wide 60 watt incandescent desk lamp or heat source Aluminum foil optional Build It Cut one Rotor 1A three Base pieces 1B and four Sides 1C two with holes and two without refer to template The cut pieces along with the needle and rubber bands should look like the photo
