Save Energy

Energy is one of the most fundamental parts of our universe.

We use energy to do work. Energy lights our cities. Energy powers our vehicles, trains, planes and rockets. Energy warms our homes, cooks our food, plays our music, gives us pictures on television. Energy powers machinery in factories.

Energy is defined as “the ability to do work.”

When we eat, our bodies transform the food into energy to do work. When we run or walk,

we “burn” food energy in our bodies. When we think or read or write, we are also doing work.

Cars, planes, trollies, boats and machinery also transform energy into work.

Work means moving something, lifting something, warming something, lighting something. All these are a few of the various types of work. But where does energy come from?

There are many sources of energy. In this guide, we will be looking at the energy that makes our world work. Energy is an important part of our daily lives.

The forms of energy we will look at include:

+ Geothermal Energy

+ Fossil Fuels — Coal, Oil and Natural Gas

+ Hydro Power and Ocean Energy

+ Nuclear Energy

+ Solar Energy

+ Wind Energy

We will also look at turbines and generators, at what electricity is, how energy is sent to users, and how we can decrease the energy we use.

Some of the energy we can use is called renewable energy. These include solar, wind, geothermal and hydro. These types of energy are constantly being renewed or restored.

But many of the other forms of energy we use in our homes and cars are not being replenished. Fossil fuels took millions of years to create. They cannot be made over night.

And there are finite or limited amounts of these non-renewable energy sources. That means they cannot be renewed or replenished. Once they are gone they cannot be used again. So, we must all do our part in saving as much energy as we can.

In your home, you can save energy by turning off appliances, TVs and radios that are not being used, watched or listened to.

You can turn off lights when no one is in the room.

By putting insulation in walls and attics, we can reduce the amount of energy it takes to heat or cool our homes.

Insulating a home is like putting on a sweater or jacket when we’re cold…instead of turning up the heat.

The outer layers trap the heat inside, keeping it nice and warm.

To make all of our newspapers, aluminum cans, plastic bottles and other goods takes lots of energy.

Recycling these items — grinding them up and reusing the material again — uses less energy than it takes to make them from brand new, raw material.

So, we must all recycle as much as we can.

We can also save energy in our cars and trucks.

Make sure the tires are properly inflated.

A car that is tuned up, has clean air and oil filters, and is running right will use less gasoline.

Don’t over-load a car. For every extra 100 pounds, you cut your mileage by one mile per gallon.

When your parents buy a new car, tell them to compare the fuel efficiency of different models and buy a car that gets higher miles per gallon.

You can also save energy in your school.

Each week you can choose an energy monitor who will make sure energy is being used properly.

The energy monitor will turn off the lights during recess and after class.

You can make “Turn It Off” signs for hanging above the light switches to remind yourself.

You can start an Energy Patrol in your school. Click the words Energy Patrol to go to another location in our Internet site that tells you how to set one up in your school.

You can make sure your classmates recycle all aluminum cans and plastic bottles, and make sure the library is recycling the newspapers and the school is recycling its paper.

Conclusion

To make sure we have plenty of energy in the future, it’s up to all of us to use energy wisely.

We must all conserve energy and use it efficiently. It also up to those of you who will want to create the new energy technologies of the future.

One of you might be another Albert Einstein and find a new source of energy. It’s up to all of us. The future is ours but we need energy to get there.

Related web sites: Generating New Ideas for Meeting Future Energy Needs

Compared to fossil fuels, sunlight is a weak energy source.

Compared to fossil fuels, sunlight is a weak energy source

Capturing sunlight is not as easy as it sounds. It is a dilute energy source, spread out over time and space. Earth receives 5.6 x 1018 (5,600,000,000,000,000,000) megajoules of solar radiation each year (Box 1), but to make it worthwhile we need to collect it over many hours and across many square metres of ground. We then need to concentrate it so as to make available the sort of power that modern society needs. Sunlight is not as energy-dense as oil but this is made up for by the fact that it is present over such a large area.

By careful design and positioning of houses we can use sunlight to warm our homes and our domestic water. This passive solar heating can help us reduce fossil fuel use (and save money) but it s not enough to replace those traditional fuels entirely.

To be most useful, the energy in sunlight must be converted to another form

Solar energy becomes much more useful when we change it to another form. Light can be changed directly to an electric current by photovoltaic cells. The efficiency with which these convert light to electricity is still too low, and their cost too high, to make them useful for many applications. Furthermore, you need to have a large area of photovoltaic cells to power something like a car – although it can be done, as demonstrated by the entrants in the World Solar Challenge car rally (Box 2).

Australian research is forging ahead on reducing the cost and improving the efficiency of photovoltaic cells (Box 3).

Many places where energy is needed are not very sunny

Unfortunately, we can t yet power our homes entirely on sunlight. Photovoltaic cells for a house are expensive, and anyway most houses are not in the sunniest part of Australia or the world. The solution is to put the sun s energy into a form which can be stored and moved around, so that we can collect it in those places where most of it falls and move it to where it is needed.

Steam or hydrogen gas are the best future conversion options

Sunlight can be concentrated by solar collectors – best sited in a desert. These focus sunlight from a large area on to a central vessel in which water is heated to become very high temperature steam. The expanding steam can power a turbine and generate electricity on a sufficiently large scale that it can be sent across a power grid. The world s largest, free-standing, steerable solar concentrating dish is in Canberra, where it forms part of the Australian National University s solar research program (Box 4).

The greatest challenge for solar energy is to power modern society s transport and industrial needs. Transport fuels must be light but packed with energy. They must also operate when it s dark, so photovoltaic cells are out. The answer for the future probably lies in hydrogen gas, derived from water split apart using solar electricity or the sun s concentrated heat (Box 5).

We are continuously getting adapted to the pollution created from burning of fossil fuels, but we absolutely cannot get adapted to the nuclear pollution.

The energy sources have been split into three categories: fossil fuels, renewable sources, and nuclear sources. The fossil fuels covered here are coal, petroleum, and natural gas. The renewable energy sources are solar, wind, hydroelectric, biomass, and geothermal power. The nuclear-powered sources are fission and fusion

You will be allowed to choose attributes of your country. A larger population requires more energy, but increases the probability that your scientists discover new energy sources. Similarly, you can determine the education level of your population. The greater the education, the more likely it is that your scientists discover new energy sources. Wealth, though helpful in maintaining your country, doesn’t last forever. Your main goal is to find lasting sources of energy, not accumulate money. Finally, you also have the ability to determine the extent of your country’s natural resources. These include oil deposits, coal mines, forests, water, and nuclear fuel.

“So Why Can’t We Just Use Fusion Now?”

Although fusion power sounds extremely attractive right now, it still has not been developed into a viable energy source. The reason is because it isn’t as simple as it sounds. Tritium and deuterium atoms don’t (thank goodness) randomly collide and give off energy. They must be heated up to extremely high temperatures (around 100 million degrees!) in order for fusion to take place.

So why can’t we just heat them up? Well, when matter is present at the high temperatures necessary for fusion, it changes into another form. We’re all familiar with the 3 main states of matter: solid, liquid, and gas. Each succeeding state is more energetic than the last. The atoms of a substance in the gaseous state move about much more than those of a substance in the solid state. Plasma, what has been called the “fourth state of matter,” consists of a cloud of charged particles and is the most energetic of the four states of matter. Plasma is the most common form of matter in the universe. In fact, stars are made mostly of plasma. Examples of this unique state of matter here on earth include lightning, neon signs, and ordinary flames.

Because plasma exists only at such high temperatures, the electrons in the atoms of a substance in the plasmid state have enough potential energy to “break free” of the nucleus. Thus, the plasma is said to be made up of a cloud of positively and negatively charged particles. The positive ions are the atoms minus the electrons (and thus have a net positive charge). The negative particles are of course the electrons themselves that have been stripped from the atoms.

One characteristic of matter in the plasma state is how difficult it is to confine. Naturally, anything present at such high temperatures is very energetic and therefore moves around a great deal, and anything that moves around a lot is hard to confine. The containment problem has become one of the biggest setbacks to the use of fusion power on earth.

Advantages and DisadvantagesAdvantages:+ The fuel for fusion reactions are readily available. Deuterium and Tritium are virtually inexhaustible. + Unlike the burning of coal or other fossil fuels, fusion does not emit harmful toxins into the atmosphere. The combustion of most fossil fuels involves some form of the reaction C + O2(g) –> CO2(g) + heat+ The carbon dioxide (CO2(g)) emitted by this reaction contributes to the global warning/so-called “Greenhouse Effect” that we’ve all heard so much about. Fusion, however, produces only helium, a gas that is already in abundance in the atmosphere and will not contribute to global warming. + A major concern with the use of fission power is the issue of nuclear waste, a dangerous material that can both directly injure people and be manufactured into weapons. Fusion has no such problems with dangerous by-products. Disadvantages+ Scientists have not yet been able to contain a fusion reaction long enough for there to be a net energy gain. + Many countries are phasing out fusion research because of the failure to reach a breakthrough

The Future of Fusion Just how soon might we be able to build fusion power plants that generate enough electricity to provide for the world’s increasing energy consumption? Unfortunately, many experts believe such prospects in the foreseeable future are bleak. One reason for such pessimism is the decrease in federal support in funding fusion research. In recent years, the U.S. Department of Energy’s Office of Energy Research has been cut forty percent (to around $230 million in 1998), forcing the program to undergo extensive restructuring. Uncertainty reached such a height that one book predicted in 1997 that the Tokamak Fusion Test Reactor, one of the most powerful in the world, “will likely” be shut down by 1998 (Blair, 1997). Budget constraints and the difficulty in producing and maintaining a net energy in a fusion reactor have forced scientists to conclude that no one country can achieve success alone. Even with funding issues aside, the task is so daunting as to be widely considered the greatest technological challenge yet unrealized. Currently, Russia, the United States, Europe, and Japan are jointly developing The International Thermonuclear Experimental Reactor (ITER). An artists’ drawing of the current ITER design. courtesy the DOE

The fate of the ITER may be indicative of the future of fusion as a whole. As reported in Science (”Fusion Facility Faces Fall Deadline”, Aug 7, 1998), the entire project is threatened because of technical and financial disagreements on a prototype design. Given the $10 billion price tag of that prototype, some researchers are now exploring a simpler and cheaper way of achieving the goal of fusion. The future of fusion, it appears, will ultimately depend on our willingness to take great economic risks now in trying to prevent a global crisis that is yet to come for some time.

It has been estimated that there are enough crude oil reserves to last the world about another 60 years. More than half of that amount is located in the Middle East in such “oil-rich” countries as Saudi Arabia, Kuwait, Iran, and Iraq. Because so much petroleum is concentrated in that area of the world, imagine how disastrous it would be if the flow of crude oil from that small collection of countries were to suddenly somehow be cut off. Just such a situation did arise during what has been termed the “Mideast Oil Crisis” of the 1970s.

Fission

Fossil Fuels Fission Hydroelectric Biomass Solar Wind Geothermal Fusion Advantages and DisadvantagesAdvantages+ Relatively little fuel is needed and the fuel is relatively inexpensive and available in trace amounts around the world. + Fission is not believed to contribute to global warming or other pollution effects associated with fossil fuel combustion Disadvantages+ Possibility of nuclear meltdown from uncontrolled reaction–leads to nuclear fallout with potentially harmful effects on civilians + Waste products can be used to manufacture weapons + High initial cost because plant requires containment safeguards

The name “solar power” is actually a little misleading. In fact, most of the energy known to man is derived in some way from the sun. When we burn wood or other fuels, we are releasing the stored energy of the sun. In fact, there would be no life on earth without the sun, which provides energy needed for the growth of plants, and indirectly, the existence of all animal life. The solar energy scientists are interested in is energy obtained through the use of solar panels. Although the field of research dealing with this type of solar power is relatively new, bear in mind that man has known about the energy of the sun for thousands of years.