Solar Energy Information That Will Have You Reaching For Your Wallet

Why all the fuss about solar energy information? Because we all have access to the world's greatest source of renewable energy and only a miniscule proportion of us are taking advantage of it – that's why!

Did you know that even though there has been a ton of publicity and a growing number of people making use of solar energy technologies, only a fraction of one percent of the world's energy consumption comes from solar sources?

But the scene is changing – and changing rapidly – and it certainly needs to if solar energy and,other forms of renewable energy are going to topple the fossil fuel crowd from their lofty perches.

So what is the key solar energy information that we all need to know and that will push us to become users and not just readers, or even worse, totally disinterested?

Key Solar Energy Information – The Potential

Our page on Advantages Of Solar Energy lists many of the well known benefits to be gained from using solar energy. On this page, however, we want to give you a bigger and wider picture.

  • The sun is the most powerful source of energy available to us, bar none.
  • The sun emits an absolutely gigantic amount of energy of which only a tiny fraction is intercepted by our planet earth.

    There is a quantity known as the Solar Constant which is the power of the sun at the earth per square metre and is approximately 1370 joules/sec/square meter. This value changes only minimally over time – hence its name.

    The area of the earth exposed to the sun is calculated by multiplying the square of the earth's radius (6400kms) by Pi (22/7) = 1.3 x 1014 sq. meters

    Now applying the value of the Solar Constant and multiplying by the earth area we get (1.3 x 1014 x 1370) = 1.8 x 1017 watts (joules/sec) which is the amount of solar energy captured by the earth every second.

    Now that's power for you and it's a fundamental piece of solar energy information.

  • The global energy consumption in 2010 was 145,375 TW-hrs(Terrawatt-hrs), expressed as 1.45 x 105 - a figure that is steadily rising, year by year.

    Now let's compare those two statistics:

    World energy consumption 2010 = 1.45 x 105 Terrawatt-hours/year

    Energy from the sun on earth's surface = 1.8 x 1017 watts

    = 1.8 x 105 Terrawatts

    = 6.48 x 108 Terrawatts/hour

    That means that there is approximately 4,000 times as much energy available in one hour from the sun as is used in a whole year.

    So there's no shortage of available solar energy!

There is a growing recognition, world-wide, that we need to move from our tremendous reliance on energy from fossil fuels to a far greater proportion from renewable sources. There are those that argue that it is too late to avoid the disastrous consequences of our continued addiction to energy from fossil fuels.

Fortunately, there are those who are a lot more optimistic and who have a vision for what can be achieved. Solar energy plays a very significant part in that big picture. Because of its large untapped potential, as evidenced by the figures we showed you above, solar energy is destined to be at the forefront of any energy transformation.

For example the German Advisory Council On Global Change envisages that from now through 2050 to 2100 there will be a steady growth in solar energy, so much so that by 2100 it will be providing 70% of world energy.

Of course such predictions rely on governments adopting the right policies and encouraging and funding their application.

A pipe-dream? Maybe - maybe not! There is considerable urgency but the fossil fuel industry is a formidable stumbling block. Still, as one commentator said, "the future for solar energy is decidedly sunny".

Key Solar Energy Information - The Developments

The availability of solar energy obviously varies from place to place so it is important to have accurate data at any location where a solar project is being developed. It is therefore encouraging to note that with the increased use of satellites for measurement data it will be possible to have that accurate data at any given place.

Solar collectors

Solar thermal collectors are used to heat air, water or other fluids, depending on the applications. The technology has now evolved so that the equipment has greater versatility.

  • Traditional flat-plate solar collectors are used to heat air, water or other fluids for home or commercial heating and cooling, hot water provision, and heat for industrial processes. These collectors are OK for temperatures up to 100°C(212°F).
  • Now there are collectors such as parabolic troughs or dishes which can produce temperatures from 100°-500°C(1060°F) and are used for various industrial processes and generating electricity.
  • In addition, we now have high temperature concentrating collectors that reach temperatures of 1000°C(2120°F) and are used for electrical power and industrial furnaces.

Solar photovoltaic panels

It is in this area that the developments have been most dramatic. The most common panels are those based on crystalline and poly-crystalline solar cells but these are rapidly being overtaken by thin-film technology where the cells are made up of thin films of cadmium telluride.

The major changes in solar panel technology are increased efficiency and lower costs. To illustrate this point, the earlier solar panels were about 10% efficient ranging up to 15-17%. Now however, panels are being produced with 30-40% efficiency. At the same time the cost per panel has dropped significantly, starting from $30/watt in the 1980's and down to 3$-$5/watt in more recent times. With the thin film technology now gaining greater market share the price is expected to reach $1/watt.

The implications for your wallet are obvious!

Solar applications

Solar energy is amazingly versatile. It can be used effectively in a growing lost of real-life scenarios...

  • Solar hot water heating is the most developed of the solar technologies and with more governments offerig subsidies fo such projects, is growing world-wide at 25% per year.
  • The use of solar heating in industry is another growing application. Almost one -half of industrial processes require heat less than 250°C (480°F) which means that the various solar collectors, referred to previously, can easily provide for this. As the cost of energy from fossil fuels continues to rise this will become the way to go.
  • Heating buildings is another development that will increase in popularity. It accounts for a substantial proportion of home and commercial building energy expenditure. Passive Solar is a fast developing area with many building designers and architects incorporating passive solar provisions into their designs. At the same time, this passive solar technology is being combined with solar panels to give an added efficiency and reduction in energy use from the grid.
  • The building industry in developing countries is an obvious point of growth for solar technologies. By having solar energy provisions at the very beginning the people in those countries will have the advantage of thinking quite differently about their energy needs - they will have effectively bypassed any addiction to energy from fossil fuels.
  • The other exciting development, again related to the building industry, is the integration of solar technologies beyond the individual home or commercial building. This is leading to the development of groups of buildings designed around solar provisions, even small towns and larger cities.
  • Concentrated solar power is another emerging technology showing great promise for the future. By using concentrated solar power on thin-film solar panels it's possible to achieve almost twice as much electricity from the same unit area- an exciting prospect that will lower the system costs proportionately.

So there you have it – a collection of solar energy information that highlights the bright future for the solar industry.

This means you can invest with confidence.

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