Last week in our discussion on energy, we briefly mentioned that plants are able to convert the sun's energy into plant mass, now let's look at that process, called photosynthesis, in better detail.
Photosynthesis: a Chemical Reaction
The illustration above shows a simplification of what is happening in the natural world involving photosynthesis. We see that the energy from the sun's light (photons) creates a chemical reaction that combines (synthesizes) Carbon dioxide (CO2) and water (H20) to create some form of carbohydrate sugar (CH2O)n and leftover Oxygen (O2).
We list the equation out below, so that you can see the overall process. In our balanced reaction, we see that glucose (C6H12O6) is our representative of a carbohydrate. The important thing here is that the byproducts of this process are extremely important for life on Earth. We have to ingest carbohydrates and oxygen to have energy to live. When our bodies metabolize carbohydrates like glucose, we oxidize sugars to release energy for physiological movement (putting our bodies in motion). The byproduct of this process is CO2 which can then be stored again during photosynthesis.
For a more in depth look at the various types of chemical reactions, check out the Khan Academy video series.
Bringing It All Back Home
Again, what does this have to do with technology? Last time, we saw that when fossilized carbohydrates (hyrdocarbons--CnH(2n+2)) are burned, stored energy is released in the form of heat. That energy is converted into electricity that powers our electrical devices. The photosynthesis of hydrocarbons is the foundation for our electrical power.
For plants to continue to grow, they need balanced access to the key components of photosynthesis: water, sunlight, and Carbon dioxide (other elements like Nitrogen, Phosphorus and Potassium are crucial as well as you shall see later this summer). That balance is the basis of all gardening and agriculture. There are quite a few resources out there to help people find that balance and make their garden the most productive.
Check out these tech resources to balance light and watering in a garden and experience photosynthesis with a deeper understanding:
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Friday, June 14, 6-9 p.m. Main Library, 301 York St.Join us for the 3rd annual Survivor Night at the Library, featuring: Mad Science, Chain Reactions, Catapults & Tower Building, Scary Stories, Kitchen Science, Michael Jacksonís Thriller... and a whole lot more!
The event is free - click here to register. Ages 12-19.
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Where do you go to try something different? These two sites show you where you can find similar titles and authors of your interest:
With Fantastic Fiction, you can find where a particular title falls in a series, an entire bibliography of what the author has published, similar authors to a particular genre, and even upcoming titles soon to be released.
NoveList offers reviews and is able to filter books/authors similar to your taste. You can even narrow down what genre of literature you enjoy. Broaden your horizons by exploring these two websites.
- Micah Followay, Shively Branch
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The Genesis of Energy on the Sun
Constant complex atomic reactions (nuclear fusion reactions, for extra credit ) are taking place on our sun called Proton-Proton chain reactions. During these reactions, Hydrogen (H) atoms are combined together to create isotopes of Helium (He). See the image below (note: MeV denotes megaelectron volts, a measure of electric energy). The result generates electricity that radiates all the way to Earth. The resulting He isotopes undergo more atomic reactions that involve Beryllium and Lithium, further resulting in a release of energy. The sun's energy is radiated to Earth in the form of electro-magnetism.
In one form or another, the energy that you use comes from the sun's electro-magnetic ray. The food that you eat transforms the sun's energy during photosynthesis and uses it to create mass (e.g. glucose sugar in plants) storing energy that your body uses when you consume and digest your food. The stored energy is also passed to your body when you consume fish and animals that eat plants.
So What Does this Have to do with Technology?
The energy that you use to power devices like your phone, TV, and computer also originates in the sun. Depending upon where you live in the world, your main source of electrical power varies. The main sources of fuel that we use in KY are coal power and natural gas (to power our homes and charge battery powered devices) and petroleum-based gasoline (to power our transportation).
Coal and oil are fossilized versions of plant and animal matter that have undergone extreme heat and pressure for millions of years. Energy in the form of heat is generated when we burn those substances, and we use that to generate electrical energy (for more on this, stay tuned for the post on Copper). So when you use your computer to update your status or play a video game, the energy that is needed to power the device originates in the Hydrogen and Helium reactions on the sun.
Alternative Ways to Harness the Sun's Energy
Since there is a limited amount of fossil fuels left on Earth, scientists have been designing alternative ways to harvest energy from the sun's rays.
The most direct way is through solar-powered energy which can be divided into two categories. First, passive solar energy harnesses just the heat given off from the sun's rays and concentrates that energy to heat water or a greenhouse, etc. Second, scientists use photovoltaic panels to actively transform the energy in the sun's rays into electricity that can be used to power batteries.
Biofuels, like bio diesel are made from low-cost, mass produced sugary plant substances like sugar cane, corn and soy. The sun's energy is stored in the plant's sugars and is distilled into a purified ethanol and used to power machines and automobiles.
Onyx Photovoltaic Estimation is a cool, free app that uses your phone's screen to estimate the amount of power that a photovoltaic panel would generate at any location.
There is a diverse world of alternative energy that is constantly changing due to technological improvements. Here's a cool app to keep you up to date from Renewable Energy World:
(Montage of alternative sources of energy: wind, hydropower, and photovoltaic cells)
Here's an extra credit question for your Teen Summer Reading activity point: how are wind-powered and geothermal electricity also forms of the Sun's energy?
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Meet Standish Treadwell. He has two different colored eyes. He canít read well. He canít write well. He isnít considered to be very bright. But after his parents were taken from him, Standish starts seeing things in a whole new way. With help from his friend Hector, his world begins to brighten. Although it may not be much, Standish finds hope in his grandfather and the Moon Man for the future. In hopes of discovering whatís being hidden by the Motherland, Standish and Hector venture to the other side of wall. What they find will blow you away.
An absolutely stunning read. I defy anyone to read this and finish with dry eyes.
If you read Maggot Moon let us know what you think. Hate it? Love it? Ambivalent? Weirded out? I would love to hear a teenís point of view of this book.
-Heather Lee, Children's Librarian, St Matthews Branch
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