HOW TO PUT THE SUN TO WORK IN YOUR HOME
by Eric Smith
Contents
APPENDIX:
Introduction
E very hour of every day enough solar energy falls on the Earth to supply the entire planet with power for a year. The energy is completely free and non-polluting; theres no danger of an oil spill, no mountaintop removal, no toxic waste, no smog, no nuclear meltdowns, and no monthly bill. Plus, it will keep coming for at least a few billion years.
The only catch is that we havent entirely figured out how to harvest as much as we need. Were making progress, but were not there yet.
This book is a primer on how you can begin. You dont have to stand on the sidelines waiting for scientists to invent the perfect solar cell. There are cost-effective, efficient ways to harvest solar energy right now. Solar cookers, solar hot water heaters and solar hot air collectors, to name a few, can all be made using standard building materials available from home centers, and they save money and energy right away. Even photovoltaic panels, which are still widely thought to be too expensive for the average homeowner, sometimes wind up being cheaper than conventional power after you factor in rebates, tax credits and money earned when you generate more electricity than you use. And if you live (or would like to live!) off the grid, solar cells are actually the cheapest power source.
The term solar power is really a bit misleading. Solar power is not just big arrays of solar panels. There are two essential strategies for harnessing solar power. The first uses photovoltaic cells to convert light to electricity; depending on the size and number of panels, cells can power anything from a pocket calculator to an entire city. However, the basic building blockthe cellshave to be manufactured. The second type of solar power involves concentrating and converting sunlight to heat; the technology to do that is simple enough to be understood by children, relatively inexpensive, and very DIY friendly. If you can glue aluminum foil to cardboard or cover a wooden box with a piece of glass you can make a working solar collector and start saving real money immediately.
In this book well explore both types of solar power, explaining how-to projects that you can build with basic tools and skills. Well show you how to heat your own water, warm up your house, dry your own lumber, make your own distilled water and do other projects that turn solar heat into reduced utility bills. Well also explain the basics of solar electricity, from battery charging and simple lights and pumps to sophisticated whole-house systems, and show you simple ways you can make use of solar electric technology right now.
Most home centers carry all the materials you need to get started with solar thermal projects like hot water heaters, and some sell solar panels and plug-and-play systems. If you want to go further and jump into more complex projects, you can find suppliers in the Resource Guide who will help you put together anything from a battery-charging station to a large, whole-house solar system.
The sun is shining. Lets get started.
Solar panels are combined with solar hot water collectors (the panels along the ridge) to provide electricity, hot water and heat for this home.
With a few photovoltaic panels and storage batteries, isolated areas miles off the electric grid, like this village on Surin Island in Thailand, can have reliable power for modern convenience.
Solar power plants are most cost-effective in parched desert areas where the sky is usually clear. This array provides power for an air force base in Nevada.
A Look into the Future
Solar technology is advancing rapidly, but the basic ideas behind it have been around for a very long time. More than two thousand years ago, Greeks, Romans, Chinese and others were starting fires by concentrating and focusing the rays of the sun, and structures have been built and oriented to collector blocksolar heat for at least that long. The first known solar cooker was used in the 1830s, and the first solar cell was developed in 1876. The photoelectric effectthe process whereby light creates electricitywas explained by Albert Einstein in 1905. Turning the abundant sunlight that falls on the earth every day into useful energy is a dream that has been pursued for centuries, but only recently has manufacturing technology advanced to the point where these dreams can begin to be realized by almost anyone.
Fossil fuels are slowly but very definitely running out, even as the worlds energy needs increase. All the fossil fuel that will ever be available on earth, including uranium for nuclear power, is less than half of the amount of solar energy received on earth every year. And solar energy will never run out.
All over the world scientists are experimenting with new materials and techniques to harvest this energy, and new ways to improve the efficiency of materials being used now, such as silicon. Photosynthesis in plants is being studied for clues about how to make better solar cells, since plants make much more efficient use of the suns energy than silicon cells currently do. Fuel cells, which can use solar power to convert water into hydrogen fuel using solar or other renewable power, are being researched as an alternative to batteries. Even impossible-sounding ideas like placing giant solar panel arrays in orbit, where they can harvest ten times as much power as they do on earth, are being seriously considered.
Even though we dont yet know what it will look like or what the infrastructure that makes it work on a large scale will look like, solar technology is our future.
Solar-powered cars get faster and more efficient every year. Races give competitors from around the world a chance to try out new ideas and show off their work. They also make the point that solar power is still very much an evolving, DIY-friendly fieldmost of the cars are put together with off-the-shelf parts by enthusiastic amateurs.
This elegant catamaran is powered by the solar panels forming its roof.
Using a solar panel
Next page