Blog archives for December, 2008

A cause for concern for many households is the price development of home essentials, such as energy. In today’s world electricity is absolutely essential. All parts of our lives are dependent on it; it is impossible to imagine our lives without it. However, this everyday commodity is getting more and more expensive due to the increasing demand and the higher price levels of oil. This means that it is more important than ever to think about how we can make savings on our energy bills. And in order to decrease our monthly electric bills, we need to look into alternative energy sources, such as installing residential solar power or wind power systems.

Residential energy supplies could supplement our dependence of energy from the grid. The sun or wind are used as energy source which is free, is recyclable and produces no carbon emissions. The three reasons just mentioned are why more and more people install residential solar or wind power devices in their homes. As per recent research, if 25% of households in the United States choose to power their homes using residential power devices, possible thousands of regular power plants could be rendered surplus. This means that there will be a lot less carbon emissions which in turn means less green house gases and a more healthy environment.

Apart from solar units here is the option of home wind turbines that are great if you want to save money on electric bills, and be beneficial for our environment and health. Wind power devices take advantage of this great sustainable energy source, the wind, which will generate energy without any damaging exhausts that could damage the ozone layer. It is a one time investment that could last a lifetime. Windmills work by using the power of the wind to rotate a turbine that creates mechanical energy. The mechanical energy created is transmitted to home wind generators that convert it to electrical energy usable for homes. Energy that is not used immediately can be stored in a battery to be used when there is no wind.

There are two major benefits from using wind or solar power systems in your home. One, you can save a lot of money by using residential power, and two - maybe even more importantly - you can help save the environment. Installing solar panels or wind power in your home is a great investment that will cut your costs for a long time; money, which cn be used for better things for your household and family. You can also save your money, by availing of the tax cuts your government may offer to people who use reusable energy. It is sometimes possible to also sell electricity if you create more energy that you actually use. You can also save the environment by using wind or solar energy because you lessen the demand of electricity produced by electric power plants that produce energy while emitting carbon.

So, not only will you save money, you can also save the environment from the ill effects of carbon emissions.

This article will describe how solar energy is created and cover some of its basic principles.

Solar energy consists of the light and heat emitted by the sun, in the form of electromagnetic radiation.

With today’s technology, we are able to capture this radiation and turn it into usable forms of solar energy - such as heating or electricity.

Although one could go into technical dissertations on the subject of electromagnetic radiation, how it is converted into solar energy, and the exact qualities of its electromagnetic rays, this is not something the average person needs or wants to know.

But in order to benefit the most from the use of solar power, there are a few facts you should know. Knowing these facts can assist you to make a sound decisions, when looking at the use of solar power as a clean energy source for your home, RV, or whatever the case may be.

- Available Solar Resource

The technical feasibility and economical viability of using solar energy depends on the amount of available sunlight (solar radiation) in the area where you intend to place solar heaters or solar panels.

This is sometimes referred to as the available solar resource.

Every part of Earth is provided with sunlight during at least one part of the year. (I say “part of the year” as the north and south polar caps are each in total darkness for a few months of the year.) The amount of sunlight available is one factor to take into account when considering using solar energy.

There are a few other factors, however, which need to be looked at when determining the viability of solar energy in any given location. These are as follows:

* Geographic location

* Time of day

* Season

* Local landscape

* Local weather

Because the Earth is round, the sun hits its surface at different angles, at different locations on the globe. This ranges from 0� (just above the horizon - a good example of this is the north pole during the winter) to 90� (directly overhead, at and near the equator).

When the sun’s rays are vertical (directly overhead), the Earth’s surface gets a maximum of solar energy. The more slanted the sun’s rays are, the longer they have to travel through Earth’s atmosphere before reaching the surface (becoming more scattered and diffuse as they go along).

The more scattered and diffuse the sun rays are, the less concentrated the solar energy is. Because the Earth is round, the polar regions never get direct sunlight, and they receive no sun at all during their respective winter months.

The Earth travels around the sun in an elliptical orbit. Because of its elliptical path, the northern hemisphere of the Earth is closer to the sun during one half of the year, and the southern hemisphere is closer during the other half of the year.

When one part of the Earth is closer to the sun, it receives more concentrated solar energy. This is the time of year that is referred to as “summer.”

But regardless of summer or winter, the 23.5� tilt of the Earth’s axis plays a larger role in determining the amount of sunlight striking Earth at a particular location. The tilting of the earth results in longer days in the northern hemisphere during one half the year, and longer days in the southern hemisphere during the other half of the year.

Areas such as the United States and Europe receive more solar energy between May and September - not only because days are longer, but also because the sun is nearly overhead during this season. The sun’s rays are far more slanted during the shorter days of the winter months. Cities such as Denver, Colorado, receive nearly three times more solar energy in June than they do in December.

- Diffuse and Direct Sunlight

As sunlight passes through Earth’s atmosphere, some of it is absorbed, scattered, and reflected.

The following is a general list of materials that cause the sunlight to be diffused:

* Air Molecules

* Water vapor

* Clouds

* Dust

* Pollutants

Sunlight affected in this way is referred to as diffuse solar radiation or diffuse sunlight.

Sunlight that reaches the Earth’s surface without being diffused is called direct beam solar radiation or direct sunlight.

The sum total of all diffuse and direct solar radiation in a given location is called global solar radiation. It is the total amount of sunlight hitting the Earth at any specific spot, both direct and diffuse combined.

Pollution and other atmospheric conditions (such as weather patterns) can reduce direct sunlight by 10% on clear dry days. They can reduce direct beam radiation by 100% on thick, cloudy days.

Note that the absence of direct sunlight does not imply total darkness, as some diffuse light will still get through.

- Measuring Sunlight and Solar Energy

Scientists measure the amount of sunlight available in specific locations during the different times of year.

They are then able to estimate the amount of sunlight which falls on similar regions at the same latitude with similar climates and conditions.

Measurements of solar energy are normally expressed as “total radiation on a horizontal surface”, or as “total amount of radiation on a surface tracking the sun”.

In this last case, the assumption is that one is using a solar panel that automatically tracks the sun.

In other words, the solar panel would be mounted on a tracking device so that the panel would remain at right angles to the sun throughout the day.

This system is primarily used for industrial setups, when it is used at all.

- Solar Energy Measurements

Radiation data (the amount of solar energy available at a given location) for solar electric (photovoltaic) systems is often represented as kilowatt-hours per square meter (kWh/m2). Direct estimates of solar energy may be expressed as watts per square meter (W/m2).

Radiation data for solar water heating and space heating systems is usually represented in British thermal units per square foot (Btu/ft2).

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Anna supports of clean living and the use of renewable energy in order to combat pollution and Global Warming, as well as the humanitarian and economic consequences of dependency on fossil fuels.

For more information on solar energy, visit Anna’s blogs, Solar Power and Alternative Energy.

You can also find a wide variety of solar power equipment, solar battery chargers, portable solar power, solar water heating, solar powered weather stations, solar fountains, solar lights, home solar panels, and more, at her Solar Power Store.

Go back 30 years and you’ll see that the green movement was positively against nuclear fuel. It seems odd that 30 years on some of the very same people are placing their hopes on nuclear power to prevent global warming. It may be that we have little choice other than to go Nuclear but “why aren’t we placing more emphasis on cleaner types of energy?” Some governments (Denmark is a good example) have already made great strides in utilising cleaner and safer forms of energy including both wind farms and solar power systems. Introduction of these alternative forms of energy have been very successful so you have to ask why other countries are placing their hopes on Nuclear Power?

The old problems associated with Nuclear Power have by no means gone away. It is still a form of energy with inherent dangers and we still have no good solution to removing nuclear waste! What is keeping us from moving to other forms of energy?

The common argument is that the cost of switching to renewable energy is far more costly than staying with fossil fuels. But what are the hidden costs of staying with fossil fuels or switching to nuclear power?

It is general knowledge that our current fuel resources are running out. With the demand for energy set to increase there is only one possible outcome. More price increases! On the other hand, the alternative energy provided by the Sun, Wind and Water is free and will be available for a very long time.

Harnessing the power of alternative forms of energy may not be cost effective at this time but future developments will surely lead to greater efficiency. For instance, take solar technology. With semiconductor technology advancing in leaps and bounds, solar panels are becoming increasingly efficient. Not so long ago solar panels could only be used with any effectiveness in warmer climates. Today, we see them being used in many types of environment. Indeed, solar technology has advanced so much individuals are investing in their own DIY Solar systems. If people think it worth their while to build and install their own solar power systems then why can’t it be done on a wider scale.

The financial problem of sticking with current energy resources is not just limited to supply. The cost of lowering our CO2 emissions or removal of dangerous waste material is a cost that will stay with us for many years. Alternative forms of energy like solar, wind and Hydro power are all clean and pollutant free. There are no hidden costs to pass on to future generations. The cost of short term thinking is a high price to pay for the future of the planet. Let’s keep nuclear power at a distance. The Sun would be far enough.

This article will describe how solar energy is created and cover some of its basic principles.

Solar energy consists of the light and heat emitted by the sun, in the form of electromagnetic radiation.

With today’s technology, we are able to capture this radiation and turn it into usable forms of solar energy - such as heating or electricity.

Although one could go into technical dissertations on the subject of electromagnetic radiation, how it is converted into solar energy, and the exact qualities of its electromagnetic rays, this is not something the average person needs or wants to know.

But in order to benefit the most from the use of solar power, there are a few facts you should know. Knowing these facts can assist you to make a sound decisions, when looking at the use of solar power as a clean energy source for your home, RV, or whatever the case may be.

- Available Solar Resource

The technical feasibility and economical viability of using solar energy depends on the amount of available sunlight (solar radiation) in the area where you intend to place solar heaters or solar panels.

This is sometimes referred to as the available solar resource.

Every part of Earth is provided with sunlight during at least one part of the year. (I say “part of the year” as the north and south polar caps are each in total darkness for a few months of the year.) The amount of sunlight available is one factor to take into account when considering using solar energy.

There are a few other factors, however, which need to be looked at when determining the viability of solar energy in any given location. These are as follows:

* Geographic location

* Time of day

* Season

* Local landscape

* Local weather

Because the Earth is round, the sun hits its surface at different angles, at different locations on the globe. This ranges from 0� (just above the horizon - a good example of this is the north pole during the winter) to 90� (directly overhead, at and near the equator).

When the sun’s rays are vertical (directly overhead), the Earth’s surface gets a maximum of solar energy. The more slanted the sun’s rays are, the longer they have to travel through Earth’s atmosphere before reaching the surface (becoming more scattered and diffuse as they go along).

The more scattered and diffuse the sun rays are, the less concentrated the solar energy is. Because the Earth is round, the polar regions never get direct sunlight, and they receive no sun at all during their respective winter months.

The Earth travels around the sun in an elliptical orbit. Because of its elliptical path, the northern hemisphere of the Earth is closer to the sun during one half of the year, and the southern hemisphere is closer during the other half of the year.

When one part of the Earth is closer to the sun, it receives more concentrated solar energy. This is the time of year that is referred to as “summer.”

But regardless of summer or winter, the 23.5� tilt of the Earth’s axis plays a larger role in determining the amount of sunlight striking Earth at a particular location. The tilting of the earth results in longer days in the northern hemisphere during one half the year, and longer days in the southern hemisphere during the other half of the year.

Areas such as the United States and Europe receive more solar energy between May and September - not only because days are longer, but also because the sun is nearly overhead during this season. The sun’s rays are far more slanted during the shorter days of the winter months. Cities such as Denver, Colorado, receive nearly three times more solar energy in June than they do in December.

- Diffuse and Direct Sunlight

As sunlight passes through Earth’s atmosphere, some of it is absorbed, scattered, and reflected.

The following is a general list of materials that cause the sunlight to be diffused:

* Air Molecules

* Water vapor

* Clouds

* Dust

* Pollutants

Sunlight affected in this way is referred to as diffuse solar radiation or diffuse sunlight.

Sunlight that reaches the Earth’s surface without being diffused is called direct beam solar radiation or direct sunlight.

The sum total of all diffuse and direct solar radiation in a given location is called global solar radiation. It is the total amount of sunlight hitting the Earth at any specific spot, both direct and diffuse combined.

Pollution and other atmospheric conditions (such as weather patterns) can reduce direct sunlight by 10% on clear dry days. They can reduce direct beam radiation by 100% on thick, cloudy days.

Note that the absence of direct sunlight does not imply total darkness, as some diffuse light will still get through.

- Measuring Sunlight and Solar Energy

Scientists measure the amount of sunlight available in specific locations during the different times of year.

They are then able to estimate the amount of sunlight which falls on similar regions at the same latitude with similar climates and conditions.

Measurements of solar energy are normally expressed as “total radiation on a horizontal surface”, or as “total amount of radiation on a surface tracking the sun”.

In this last case, the assumption is that one is using a solar panel that automatically tracks the sun.

In other words, the solar panel would be mounted on a tracking device so that the panel would remain at right angles to the sun throughout the day.

This system is primarily used for industrial setups, when it is used at all.

- Solar Energy Measurements

Radiation data (the amount of solar energy available at a given location) for solar electric (photovoltaic) systems is often represented as kilowatt-hours per square meter (kWh/m2). Direct estimates of solar energy may be expressed as watts per square meter (W/m2).

Radiation data for solar water heating and space heating systems is usually represented in British thermal units per square foot (Btu/ft2).

————————

Anna supports of clean living and the use of renewable energy in order to combat pollution and Global Warming, as well as the humanitarian and economic consequences of dependency on fossil fuels.

For more information on solar energy, visit Anna’s blogs, Solar Energy and Alternative Energy.

You can also find a wide variety of solar power equipment, solar battery chargers, portable solar power, solar water heating, solar powered weather stations, solar fountains, solar lights, home solar panels, and more, at her Solar Power Store.

A new solar energy technology solution has been put to the test, and has been given the go-ahead for production in Australia.

This new solar power station is based on solar tower technology designed in Germany. The most fantastic thing about this new technology is the simplicity of its design, and its ingenious use of basic principles of physics to create energy.

So what is this new solar energy plant? This new solar tower, also referred to as a “solar chimney,” uses solar power to turn wind turbines.

Solar energy to turn wind turbines? How does this work? Well, the simplest way to describe it is to compare it to a huge greenhouse with a large chimney. As we all know, hot air rises. The greenhouse within the solar chimney system captures the heat of the sun. The heated air in the greenhouse is then allowed to escape through a huge chimney.

Before the air escapes through the chimney, it is forced to pass through wind turbines, which are in turn used to generate electricity. You can see a diagram of it here. The beauty of this technology is that it uses centuries-old tried-and-true principles of updraft. This is the same principles used for chimneys in open fire places. When you light a fire in your fireplace, your house doesn’t fill up with smoke. This is because of the suction which is created by the hot air rising up through the chimney.

This pulls the smoke up through the chimney as well. But in the case of the solar tower, we are not using a fire to create hot air. We are simply allowing the sun to do its thing: heat stuff up. In this case, the sun heats the air up, and the air rises through the solar chimney as a result. Australia is the first country to build this type solar energy power plant for commercial use. The central tower will be over 3000 feet high and 400 feet in diameter. It will use 750,000 cubic yards of concrete. The solar energy collector (greenhouse) will contain thirty-million square yards of space.

That’s more than three and a half miles in diameter. It will have 32 wind turbines placed at ground level, each capable of creating 6.25 megawatts of electricity. It will take 34 months to construct. It will provide a total of 200 megawatts, which is enough to provide solar power in the form of electricity, for over 200,000 households. The solar tower will create absolutely no carbon emissions, greenhouse gases, or other pollutants in its energy generation process. In other words, it is going to be 100% eco-friendly.

Learn more about solar power and alternative energy at the author’s website on Solar Power. You can also find a variety of Solar Panels and other solar-powered or wind-powered equipment at the Solar Power Store.