Interesting Facts about Electricity.

I am your sun, a golden star.
When we look up at the sky at night, almost everything we see out there is is different from the stuff that we're made of, or that elephants and rice and fleas and the oceans and the earth and stars are made of.
Ninety-five percent, or almost all of what is out there in space, is either dark matter or dark energy, and nobody knows what these are -- yet.

But we do know something about the 5% of matter that makes up the stars and planets, the matter that we can touch and see and feel. All this matter is made of atoms. Atoms have a central nucleus usually made of a proton and a neutron, with electrons spinning around the nucleus in different levels at specific, set distances away. It's sort of like you're holding a ball attached to a string, and you can whirl the ball in any direction you want to, but it always stays pretty much the same distance away from your hand. This specific set distance from the nucleus is called the electron's valence. Different valences hold different numbers of electrons. Most atoms usually have the same number of electrons as they have protons and neutrons: hydrogen atoms have one of each, carbon atoms have 6, oxygen 8, and so forth.

Scientists have discovered that the universe is between 12 and 14 billion years old. Our sun is only about 4.5 billion years old. It is a third-generation star, which means that other stars were formed, and then died, two times before our sun came into existence. The sun is made of atoms that are getting squished because there are so many of them being attracted to each other together and their mass is so HUGE. The sun is mostly made of hydrogen: one proton, one electron. The hydrogen atoms are getting so squished that their nuclei are fusing together to form new, bigger atoms with 2 protons in the center and 2 electrons spinning around them. But these new atoms are no longer hydrogen. They are a different kind of atom called helium - from the Greek word for sun, helios.

As the atoms in the sun get fused, they give off energy, and this energy travels all the way to the earth as electromagnetic waves. Just as atoms are different because they have different numbers of protons and electrons, waves are different because they are longer or shorter. The longest waves are radio waves, then microwaves, infra-red, then visible light, ultraviolet light, x-rays and the shortest waves of all, gamma rays. Light is just the tiny part of the spectrum we can see. All waves shorter than infra-red are strong enough to knock electrons right out of their valences.

A dam! You humans stop the flow. My energy is trapped.
The power from dams comes because the farther any mass such as water falls, the more energy it gives to what ever it hits -- for example, the blades of a turbine. Electricity from dams is called hydroelectricity, and we get about 7% of our power this way. Some dams last a long time. The Hoover Dam in the United States has been producing electricity since 1936 -- even though its original main purpose was to control flooding. Unless there is a drought, water fills the dam and is available to make electricity all the time, day in and day out. But if there is a drought, there is less flow and therefore less -- or no -- electricity. Hydroelectricity has other problems:

When a dam is built, everybody living on the land behind it must move. In some countries, such as India and China, this means that thousands and even millions of people lose their homes. If the dammed river is full of silt, the silt gets trapped behind the dam, so eventually the dams fill up with dirt and become useless. Before the dams were built, the silt was fertile soil for farmers downstream, whose fields were built up and revitalized by it every year when the rivers flowed over the banks. All dams change the downstream ecology, because they release a certain amount of water each day throughout the year, whereas before the dam was built, the flow changed with the seasons. Some dams have fish ladders built beside them so salmon and other migratory fish can continue to swim upstream to their spawning grounds. Some dams release more water for farmers in the growing season. And now, in some places, people are using the energy of river flow - without dams - to produce small amounts of electricity.

The wires hum! Electricity flows, pulsing, pulsing, pulsing
my energy out to your towns and cities.
But what IS electricity? Electricity is a surge of energy that makes electrons crash against each other so hard they get knocked out of their valences and crash into other electrons, which leave their valence and crash into other electrons, which leave their valence and crash into other electrons . . . . so the energy gets passed along as moving electrons. We use copper wire to carry electricity because the outside electrons in copper (and other metals, but these metals are either more rare and therefore more expensive, or they are less efficient) are very loosely attached to their nuclei, so it's easy to knock them out of their valences.

Something got left out of these pictures: the transformers. Transformers are coils of wires that increase or decrease the voltage or force of electricity: they "transform" the voltage going through wires. If you send electricity from a coil with 10 loops into another coil with 100 loops, you have 10 times more voltage in that second coil! The higher the voltage going through a wire, the less electricity is lost to resistance in that wire, so power plants have transformers nearby to increase the voltage and send it over the power lines more efficiently. At the end of the power lines, different transformers then DECREASE the voltage so smaller amounts can go to each neighborhood or group of buildings in a city.

The electric wires in your house are insulated. This means they are covered in plastic, which doesn't carry electric current, so the current can't flow into you and hurt you. The wires of transmission lines do not have insulation. Why? Because nothing touches the wires to take the current away. Notice that the wires do not touch the metal towers but are kept away by insulators, usually made of ceramic or glass. If the wires did touch the towers, the electricity would all flow down the metal structures and disappear into the ground.

But some electricity is lost as it travels through the line - usually something less than 10%. For example, the transmission lines carry electricity 1500 kilometers or about 950 miles from from the HydroQuebec James Bay Complex in Canada to Boston, Massachusetts, and they lose about 9% of their electricity along the way. This is true for lines transmitting electricity not just from hydroelectric plants, but from all other sorts of power plants as well.

There is another sort of electricity in this picture: lightning. Lightning occurs when the bottoms of clouds become full of negative energy and the earth's surface becomes more and more positive, until suddenly so many electrons shoot down in such a powerful stream that the air around them explodes. Thunder is the sound of that explosion.

Swish! Swoosh! The wind pushes blades of turbines round and round, spinning my energy to generators, which make electricity.
"Farms" of 50 or even hundreds of wind turbines have been built now, and they work best where there is a strong constant wind, such as on top of low hills or by the sea. The longer the blades and the faster the wind blows, the more electricity they produce. Wind turbines are cheap, produce no pollution, and last a long time. Here are some facts about wind turbines from the Danish Wind Industry Association:
1. Wind turbines produce almost 20% of all the Danish power consumption, and they will cover 25% by 2008.
2. During its lifetime, a wind turbine produces 80 times more energy than is used in its production, maintenance AND scrapping. (In other words, the Danes include the recycling costs of the turbines as part of their total energy. The United States does not do this when we figure out the cost of our oil or gas. The cost of recycling and cleaning up after our oil production and refining would be very, very, very, very high.)
3. The offshore foundations of the turbines increase the local variety of marine animals.
4. The Danish wind industry has created 20,000 jobs in Denmark.
5. Half the turbines are owned by local wind turbine cooperatives.
6. The energy of the wind more or less follows the human 24-hour power consumption cycle. In other words, there is not much need to store electricity for 'off-hours'.

Green plants catch my light and use my energy to help build leaves and stems.
This is photosynthesis: the ability of chlorophyll to catch sunlight and use it to break water and carbon dioxide apart and build them into sugar. The sugar holds the energy in its structure. When sugar breaks down, it gives the energy to the plant so the plant can live and grow. But the plant gives something off when it makes sugar. It gives off oxygen, sending it out into the air, where humans and other animals use it to breathe and live.

Of course trees and bushes are a fuel that can burn to produce electricity, too. A few power plants do burn them, but we now use trees mostly for building materials and furniture. Some towns and cities make electricity by burning garbage, but they need very special contraptions to remove all pollutants from the smoke so they don't get into the air.

Other plants die and are buried. Some were buried millions and millions of years ago and turned into coal.
Coal is made of ancient plants and animals, so it is called a "fossil fuel". Sometimes you can see fern fossils in a chunk of coal. The two other fossil fuels are oil and gas. Fossil fuels are mainly made of carbon. They were formed over millions of years, probably by carbon-rich plants and tiny animals getting buried underground. As millions and millions of years went by, new kinds of plants and animals developed as the air lost more of its carbon -- because it was being buried! - but this took place over millions and millions of years.

Crunch! Roar! Now you humans dig up the coal. You haul it out and burn it.
About half the electricity used in the United States comes from coal, and there is still a lot of coal underneath this country. But there are many, many problems with coal, oil and other fossil fuels:

1. Climate changes In only a couple of hundred years, humans have put huge amounts of carbon back into the air when Nature took MILLIONS of years to take it out. This carbon joins with oxygen in the air and turns to carbon dioxide, which keeps more warmth of the sun in each molecule, so the air becomes even more like a blanket around the earth.
Already, the earth has heated up by a couple of degrees over the last hundred years. It seems like a small amount, but this small amount has already caused ice to melt in the Arctic. White ice reflects most of the sunlight that hits it back into space. Now as the ice disappears, the dark seas are absorbing the sunlight, and helping to warm up the earth even more.
As the ice has melted, so the tiny plants and animals that live in the ice and the coldest waters are dying, and the fish who eat the plants and animals, and the seals who eat the fish, and now the polar bears that eat the seals are dying. As the oceans heat up, fish and the plants they eat are moving farther and farther north. The plants and other animals that cannot move, like corals, are dying. And in the far north, the animals and plants have no colder place to go, so they are dying, too.
As the ice melts, the meltwater flows into the sea, and so the oceans are rising and flooding low islands and low countries all around the world. In the tropics, the surface water has heated up so that more and stronger hurricanes are forming. These storms are especially dangerous for places where the waters have risen and flooded the land. The increasing temperatures are causing all sorts of sudden changes around the globe, including droughts in some places and heavy rains and floods in others. All these changes are happening very, very fast.

2. Limited amount The amount of fossil fuels in the ground is limited. We will soon run out - and yet we are consuming more and more and more of them every year. The United States used to have a lot of oil underneath our land and just offshore, but in 1972, the amount of oil we pumped out of the ground began to decline. Every year we pumped up less and less. But instead of learning how to conserve the oil, how to use it wisely and develop alternative kinds of energy, the US just began to buy oil from other countries. All of our oil used to come from inside our own country. Now over half of our oil comes from outside, and it costs more and more as it becomes more rare. Now around the world, people are beginning to fight over control of oil. We are beginning to have wars because of oil.

3. Pollution Mining and burning coal and oil cause pollution. When coal and oil burn, they give off sulfur, which makes rain acidic. Wherever this rain falls, it harms the lakes, plants and soil. When fossil fuels burn, they also give off gases like carbon dioxide and nitrous oxide. These are greenhouse gases that absorb heat and thereby make the earth's climate warmer. When coal burns, it gives off small particles of ash which get into our lungs and cause breathing problems. Also, tiny bits of radioactive elements like uranium and thorium are in the ash. They float in the air and fall into the soil near the coal-fired power plants and harm people living nearby. The newer power plants have equipment that lowers the amounts of these chemicals and particulates getting into the air, but many old power plants do not.
Pollution also results from mining and transporting fossil fuels: The mines where coal was once dug often fill up with water, which drains into the streams and rivers. The streams and rivers become so acidic that fish and wildlife living downstream are killed.
Oil is carried from the oil wells to other places in barges. Sometimes the barges are wrecked, the oil leaks out, the creatures living there die, and the seashore becomes polluted for years.
So far, the costs of cleaning up all the different kids of pollution from mining, transporting and burning coal, oil and gas have not been added into what we pay for them, so they are cheap. But cleaning up after them will cost billions and billions and billions of dollars, and someday we will have to pay.
Climate change
Limited supplies
Pollution
These are the three most important reasons why we need to do every-thing we can to develop alternatives to fossil fuels.

Since fossil fuels cause so many problems, we need to start using the alternatives RIGHT NOW!

My light falls on solar cells and charges their electrons. No turbines, no generators - electricity streams across the cells, which pour it into copper wires.
Solar cells do not make any pollution once they are working, and they have no turbines or other motor parts. Even though the efficiency of solar cells will improve much more - because we are only beginning to learn how to make them - it takes only 2-4 years of use for them to pay that energy back in electricity they produce. After that, all the electricity they make is completely "free": it produces no waste or pollution, no CO2 or nitrous oxides, requires no transmission lines or pipes or motors or anything at all except some copper wires leading into your house. And the sun shines on everybody, so the struggles over ownership just disappears.
Since solar cells only work when the sun is out, we need batteries to store their energy when the sun doesn't shine - IF we want all the electricity to come only into our own house. But most solar power is attached to the "grid" - the power network of your local utility. When your solar panels make more energy than you can use in your own house, the extra power goes into the grid, for everybody else to use. In some states, like California, the utility company pays you back for the extra electricity they get from you!
Engineers are improving solar panels all the time. Now there are even roof tiles made from solar cells, so you don't need tiles or shingles on your roof; you can use solar tiles instead. Most solar panels need to cover a lot of surface area to catch the sunlight, so all we need to do is cover the roofs of our schools and community offices and hospitals and rec buildings, etc., and we will have LOTS of energy - for almost nothing!

The black boxes to the far left of the picture look like solar cells, but they don't have the grid on them. They are solar water heaters, and this is how they work:

Black absorbs heat better than any other color does, so on their roofs people put black containers full of a liquid that doesn't freeze. In the sunlight, this antifreeze heats up. The hot liquid is then piped down to a big tank full of water in the basement. The antifreeze stays inside the pipes but transfers its heat to the water. This goes on all day long, until the water in the tank is VERY hot. People can then either use the hot water for washing clothes and dishes and taking baths, or they can use it to heat their houses. This is not electricity, but it is a very cheap and convenient way to heat water and a house.

From rushing wind and water, from burning coal, from silent solar cells, you let my energy into your room.
Does any of our electricity NOT come from the sun? Yes. Some of our electricity comes from nuclear energy, which comes from the breakdown of radioactive elements like uranium that are in the ground. Geothermal energy is heat from deep in the earth or from underground hot springs. Iceland gets almost all its electricity from geothermal sources, because the country sits on top of active volcanoes. A very small amount of electricity around the world is made from turbines that are turned by the action of waves and of rising and falling tides. This water action is mostly driven by the moon as it rotates around the earth and pulls the oceans after it.

But even more than we need to discover new ways to make electricity, we need to use less of it every day: insulate our houses better, use white roof tiles instead of black - or use photovoltaic roof tiles - , build overhangs and plant trees on the south of our houses to keep out the summer sun, use triple-pane windows, make more energy-efficient appliances and turn off lights and other appliances when we aren't using them. In most houses in the US today, appliances that are on "standby" - like DVDs, TVs, computers and coffee machines - use between 5 and 15% of a household's electricity every day. That alone is a LOT of wasted energy!

SAVING ELECTRICITY AND USING IT WISELY ARE EVEN MORE IMPORTANT THAN MAKING IT IN NEW WAYS.

Then, like the starlight from which it came, it fades back into space.
The earth captures sunlight - energy from the sun. This energy powers the weather, sustains life, and produces electricity. A by-product of all this activity on earth is heat: our bodies give off heat when we exercise; light bulbs give off heat along with light; motors generate heat when they turn. Although the earth is much cooler than the sun, it is still much warmer than the surrounding vacuum of space, so the earth radiates this waste heat away into space. Right now, the earth radiates away about the same amount of energy as it receives from the sun. This is a very good thing, because if it didn't, the earth would get very, very hot! This heat energy goes off as infra-red radiation. So our planet absorbs visible high-energy light from the sun and uses it to do work, which generates heat. This "waste" heat is then radiated back into space as low-energy infra-red radiation. It will never be sunlight again.

Blue Sky Press
Publishing date: March, 2004