Solar Heating
The sun provides us with heat and light that is essential to life all year round. One of the most efficient ways of harnessing the sun's energy is to use it to space heat our buildings, and produce hot water for our daily needs, such as washing, cleaning, and cooking. When you think about the truly tremendous amount of heat that the sun produces, it seems absolutely ridiculous that we should want to burn our precious fossil fuels to heat things up. We can use the sun to directly heat our...
Www.scienceconnection.com Tech Advanced.htm
One school of thought advocates positioning your solar panels on a fixed surface such as a roof, positioned so as to harness as much sun as possible on average over the year. This approach certainly works, but as we saw in Chapter 3, the sun is not a fixed object in the sky it moves, and so this approach is not necessarily the best. One other solution is to actively track the sun using a device such as the trackers shown in Figures 14-1 and 14-2. What this entails is using motors, hydraulic...
How do they work
First of all, let's cover a little bit of the theory. Ordinary silicon forms into a regular crystalline structure. If you look at Figure 10-3, you can see the way that the silicon atoms align themselves into a regular array. To make silicon semiconducting, we can take a little bit of another chemical, in this case boron, and Figure 10-3 Plain old silicon its atomic structure. Figure 10-3 Plain old silicon its atomic structure. introduce it to the silicon. Where there is a boron atom, there is...
Solar Cooling
In hot climates, it can often become uncomfortably hot in the modern world, we tend to look toward air conditioning to provide a comfortable internal atmosphere however, air conditioning often leaves us with dry stale air. While it would seem to be counterintuitive to use the sun to cool things down, there are a number of techniques that we can use to cool things down by employing the sun's energy. The amount of energy that air conditioning consumes is truly tremendous. In addition to this, the...
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Figure 15-19 Centurion solar plane. Image courtesy NASA. Figure 15-19 Centurion solar plane. Image courtesy NASA. Figure 15-22 Helios fuel cell diagram. Image courtesy NASA. Figure 15-22 Helios fuel cell diagram. Image courtesy NASA.
Tools Jcv
To make a photovoltaic cell we need silicon, this project is going to show you how solar cells are produced from crystalline silicon. The words crystalline silicon should indicate to you that this type of solar cell is made from crystals of silicon. We saw earlier how silicon aligns itself into a regular crystalline array, now we are going to look at growing this crystal. In industry, silicon crystals are grown to form a uniform cylinder of silicon which is used as the base material for...
BEAM robotics
BEAM Biology, Electronics, Aesthetics, and Mechanics robotics differ from traditional robotics in one important respect whereas conventional robotics tends to employ a central processor and some software to dictate the behavior of the robot, BEAM robotics has a different approach. The robotic behavior is governed by simple circuits which interact with each other in defined patterns. The great news is that all of the above is available in a kit from Solarbotics. Check out www.solarbotics.com for...
History of the solar still
Solar stills are an old, tried and tested technology the earliest record of a solar still being used is in 1551, when Arab alchemists used one to purify water. Mouchot, whose name also springs up a couple of other times in this book also worked with solar distillation around 1869. The first solar still, in the sense that we would recognize it now, was built in the mining community of Las Salinas in 1872, in the area which is now northern Chile. It was created by a Swedish technologist by the...
How do photochemical solar cells work
Take a peek at Figure 11-1, in the top image, we can see the energy transfers taking place the light striking our photochemical solar cell, generating energy and turning the shaft of the electric motor, which is connected to our cell. The radiated energy from the sun in the form of light, is being transformed through a chemical process into electrical energy, which travels through the circuit to the motor, where electromagnets turn the electrical energy into movement kinetic energy . We need to...
Positioning Your Solar Devices
It is important to note that the position of the sun in the sky changes from hour to hour, day to day, and year by year. While this might be interesting, it is not very helpful to us as prospective solar energy users, as it presents us with a bit of a dilemma where exactly do we point our solar device The ancients attributed the movement of the ball of fire in the sky to all sorts of phenomena, and various gods and deities. However, we now know that the movement of the sun through the sky is as...
How does a Fresnel lens work
To understand how a Fresnel lens is constructed and works, we are going to need to do a little thought experiment. Picture this. You have a glass lens which is flat on one side, and round on the other. We are now going to use a tool to remove material from the center point of the lens. The tool has a flat end. We are going to remove material until the corners of the flat-ended tool just begin to penetrate the round surface. We are now going to use another larger tool to remove material from a...
Contents
Foreword by Willie Nelson Acknowledgments 3 Positioning Your Solar Devices 17 Project 1 Build a Solar-Powered Clock 20 Project 2 Build Your Own Heliodon 22 Project 3 Experimenting with Light Plate Collector 31 Project 5 Solar Heat Your Swimming Pool 33 Project 6 Useful Circuits for Solar Project 7 Solar-Powered Ice-Maker 42 Project 8 Build a Solar Hot Dog Cooker 46 Project 9 Build a Solar Marshmallow Melter 48 Project 10 Cook Eggs on Your Driveway Project 11 Build a Solar Cooker 50 Project 12...
Parabolic dish concentrators
Dishes are great for concentrating dispersed energy to a focal point. Take a look at any residential neighborhood, and you are bound to see a menagerie of dishes the state flower of Virginia sticking out of the side of houses everywhere What do you think these dishes are doing Acting as concentrators They take the waves emitted from satellites far above the earth's surface, and concentrate them into a focal point which strengthens the signal. Similarly, you might have seen some of the world's...
Project Build Your Own Solar Phone Charger
Car charger suitable for your cell phone for cannibalization Figure 13-3 A solar-powered phone albeit not all that portable. Figure 13-3 A solar-powered phone albeit not all that portable. 274 k resistor 1 tolerance 100 k resistor 1 tolerance MAX 630 CPA integrated circuit It's the same old story just when you want to talk on your cellphone, the battery goes flat and the conversation is irretrievably lost Invariably, you haven't got your phone charger on you, and even if you did have it...
Solar vehicles
At the moment, solar cars aren't really practical for you and I to drive about in simply too much surface area is required to mount the solar cells. 4J Also, some method of storing the solar energy M needs to be employed for when your car goes into O a tunnel or the sun hides behind a cloud. Even so, solar vehicles such as the Honda Dream shown in Figure 15-1 are an interesting demonstration that fl Check this website about solar vehicles for some iH cool information it is possible to produce a...
Solar trackers in the real world
Now we have built a model, let's take a look at a real solar tracker and gain some insight as to the capabilities of the technology. Here, it was decided that solar trackers were the way forward, as the roof structure of the house on the property was not strong enough to support a solar array, and the rafters were irregularly spaced making it difficult to install mounting hardware. As the property was surrounded by a lot of land, it was decided that it was cogent to install a stand-alone array....
Project Simple Solar Tracker
We have three CdS photoresistors Figure 14.3 The value of these resistors is about 5 k when not exposed to light. However, when we expose them to light their resistance decreases to around about a couple of hundred ohms. The third CdS cell is mounted in a shrouded enclosure so that it is only illuminated when it faces directly toward the sun. When the sun illuminates this photocell, its resistance drops, and as a result, when the sun shines on it, our Darlington pair is kept off. When the sun...
Project Build Your Own SolarPowered Torch
1x AA 600 mAh NiCad battery 220 k 4 W carbon film resistor 100 k 4 W carbon film resistor 91 k 4W carbon film resistor 10 k 4W carbon film resistor 560 R 4 W carbon film resistor 2x 3.3 R 4 W carbon film resistor C9013 NPN transistor C9014 NPN transistor C9015 PNP transistor 300 pF ceramic capacitor 100 nF ceramic capacitor CdS photocell 47 k 10 lux In lists of made-up useless things, solar-powered torches seem to come out somewhere at the top. After all, what use is there for something that...
Project Build a Solar Bird Engine
Happy Drinking Bird won't be so happy when we are finished We are going to have to kill a bird to execute this project luckily the bird in question is Figure 12-1 The Drinking Bird in its box. Figure 12-1 The Drinking Bird in its box. a cheap toy from the Far East, so our consciences are clear The Happy Bird, Happy Drinking Bird, Drinking Bird, Tippy Bird, Sippy Bird, Dippy Bird or any one of a number of ridiculous names is a cheap novelty toy Figure 12-1 . It is also a serious scientific...
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Figure 13-4 Solar-powered phone charger schematic car charger. Figure 13-4 Solar-powered phone charger schematic car charger. Figure 13-5 Solar-powered phone charger schematic USB type. Figure 13-5 Solar-powered phone charger schematic USB type. Project 3M Build Your Own Solar-Powered Radio Ferrite rod antenna 60-160 pF variable capacitor BC183 transistor 10 nF capacitor 0.1 mF capacitor x 2 470 pF capacitor 220 R resistor 1 k resistor 100 k resistor x 2 10 k potentiometer Speaker PV cell A...
Project M Build Your Own Solar Airship
Solar airship tube 8 m of thin plastic tube This project is one of the most ridiculously simple projects in this book, yet it is also one of the most visual and almost counterintuitive. You might be under the misapprehension that to get things into the air you need sophisticated jet engines or rocket thrusters. Certainly if you have The kit for this project is well worth the spend, if only for the enormous scale of the airship it is a massive 8 meters long. However, if you want to experiment,...
Hint Txg
If you have access to nitric acid, you can use this as a superior method for removing the upper cupric oxide layer. You will see a black crusty oxide form on top of the copper plate. If you leave the plate to cool slowly, the crusty layer should become fairly fragile and separate easily from the underlying copper. When you have allowed the plate to cool thoroughly, give the plate a firm bang edge-on to a hard surface. Some of the oxide will pop off. Rub the oxide gently with your fingers under...
Where can I get a Fresnel lens
Here are a few ideas for procuring a Fresnel lens, both second hand and new, cost varies widely Car reversing lenses are a great source, like those pictured in Figure 8-18, these are often fairly small with a fairly coarse lens, but will certainly do the job and provide many fun hours of experimentation Fresnel lenses are often sold in small credit card or slightly larger sized flat plastic printed versions in bookshops. They are often sold as a bookmark, which doubles up as a text magnifier...
Project M Looking at the LightRbsorption Properties of Chlorophyll
Colored filter gelatin red, green, and blue If you are not sure where to get filters from, ask in a good photographic suppliers or stage lighting shop for colored gelatin. If this does not work, you could always use the clear colored plastic that some sweets are wrapped in, carefully joined with sticky tape ensuring that the joins are good and no additional light penetrates. We have seen in a previous experiment that for the photosynthesis process to occur, light is an essential component. We...
A few experiments that you can do with a Fresnel solar concentrator
Use a thermometer to measure the temperature of the point where the sun's energy is concentrated see what difference it makes if the bulb is covered in tin foil or black paper. The intensity of the concentrated light might be enough to singe a feather, or even a thin shaving of rubber from a balloon or latex glove. Try shining the beam of light onto a photovoltaic cell connected to a multimeter and load see how it affects the amount of power produced. You might also want to see if you can melt...
Photosynthesis experiments
In the following experiments, we will be analyzing the solar-driven processes that happen in plants, to produce usable products which we can burn as biofuels. The process which we have explored already, is called photosynthesis. Sugarcane, rapeseed, and other crops which are generally used to produce biofuel are a bit big, hard to manage, and unpredictable. For this reason, we will be modeling the production of biofuel crops using a small, more manageable plant salad cress mustard. To give you...
What is a fuel cell made up of
If we were to take a fuel cell to bits, we would see that it is mechanically very simple. Take a peek at Figure 17-2. We can see that the fuel cell has two end plates. These are used as a casing for the fuel cell. They help contain the internal elements furthermore, they provide an interface to the connection for hydrogen and oxygen gas. Next up are the electrodes. These are the pieces that allow us to tap off electricity. They are Figure 17-1 Fuel cell technology focus. Figure 17-1 Fuel cell...
What does it take to solar power my home
Producing electricity by photovoltaic cells is fairly expensive compared to other types of generation. However, when considering the cost of solar energy, figure in all of the carbon emissions that you aren't producing, and the toxic waste that you aren't making. We now know that solar cells can be used to generate electricity, but the problem is getting it in a form that we can use in our homes. Sure, it is possible to run a few simple bulbs from a DC supply, but to run most of our household...
Slice and dope your silicon crystals
Slicing an egg with an egg slicer is much like the process that happens when a solar cell is manufactured. Each slice of silicon is then called a wafer. We now need to create a p-n junction in the wafer to do this phosphorus is diffused into the surface of the silicon. Dip your egg into some food coloring or beetroot juice, and you will see that the juice covers one surface of the egg slice. Now, imagine that slice of egg were a solar cell, with the beetroot-soaked face pointing toward the...
The environmental cost of transportation
The city of Los Angeles in the U.S.A. is an example of a city that has learnt to pay the price for heavy use of transportation. The city's urban planning has dictated that people use their own private vehicles, as public transportation is poor. Transportation uses the bulk of the world's petroleum. We use petrol or gas depending on which side of the pond you come from , because it is an energy-dense, readily-available at present fuel, which provides power-on-demand when we want it. However,...