SOLAR POWER: A BRILLIANT POWER SOURCE

A group effort:

SYED ARHAM ALI (21)

SYED HASSAAN MURTAZA (22)

IRTIZA JAFFERY (23)

IRTIZA WAHIDI (24)

What Is Solar Power/Energy?

Solar power is the generation of electricity from sunlight. This can be direct

as with photovoltaic (PV), or indirect as with concentrating solar power (CSP),

where the solar furnaces use giant mirrors to focus the sun’s rays on a

boiler. Steam from the boiler is used to make electricity. Solar power

provided 0.02% of the total world energy consumption in 2008. Terrestrial

solar power is a

predictably inter mittent energy

source, meaning that

whilst solar power is not

available at all times, we can

SOLAR POWER: A BRILLIANT POWER SOURCE

predict with a very good degree of accuracy when it will and will not be

available. These store spare solar energy in the form of heat which can be

made available overnight or during periods that solar power is not available

to produce electricity.

Solar Energy: An Over ViewAs solar power does not make sense for all

locations in the world. The initial cost of

installing solar panels or other sources of

solar energy is high, and that is not easy for

most people to get around. No matter how

much some people would like to get

involved in the movement to

independent energy, it is cost prohibitive. To

achieve the highest level of efficiency,

which is the entire point of going solar in

the first place, you need the proper amount of roof space to support the

panels your house may require. Not only how much space is available, but

also the location of your home is also relevant to whether or not you can

maintain solar energy. Some houses simply do not receive enough sunlight

to produce substantial energy. This could mean that either your house is not

positioned favorably in relation to a tree or other house.

PhotovoltaicsA solar cell, or photovoltaic cell (PV), is a device that converts light into electric current using the photoelectric effect. This is based on the discovery by Alexander-Edmond Becquerel who noticed that some materials release electrons when hit with rays of photons from light, which produces an electrical current. The first solar cell was constructed by Charles Fritts in the 1880s. Although the prototype selenium cells converted less than 1% of incident light into electricity, both Ernst Werner von Siemens and James Clerk Maxwell recognized the importance of this discovery.

SOLAR POWER: A BRILLIANT POWER SOURCE

Following the work of Russell Ohl in the 1940s, researchers Gerald Pearson, Calvin Fuller and Daryl Chapin created the silicon solar cell in 1954.

These early solar cells cost 286 USD/watt and reached efficiencies of 4.5–6%.As of late 2009, the highest efficiency PV cells were produced commercially by Boeing/SpectroLab at about 41%. Other, similar, multi-layer cells are close. These are very expensive however, and are used only for the most exacting applications. Thin film PV cells have been developed which are made in bulk and are far less expensive and much less fragile, but are at most around 20% efficient. The most recent development (from Caltech, March 2010) is the experimental demonstration of a new design which is an 85% efficient photon absorber in plain sunlight and 95% efficient absorber at certain wavelengths. Unfortunately, 100% absorption should not be confused with 100% electrical efficiency as single junction materials are bound by the so-called Shockley-Queisser limit.

Energy storage methods

Solar energy is not available at night, making energy storage an important issue in order to provide the continuous availability of energy. Both wind power and solar power are intermittent energy sources, meaning that all available output must be taken when it is available and either stored for when it can be used, or transported, over transmission lines, to where it can be used. Wind power and solar power can be complementary, in locations that experience more wind in the winter and more sun in the summer, but on days with no sun and no wind the difference needs to be made up in some manner.

Pakistan is most suitable for solar power

In Pakistan, there is enough potential for solar energy, as there are 250-300 sunny days a year in many parts of the country. Continuous cloudy days are also rare. Solar energy can be used for rural electrification, water heating, pumping water from wells and for cooking purposes. As you can see, the cons of implementing solar power in your home are primarily cost and

SOLAR POWER: A BRILLIANT POWER SOURCE

location related, but if those two items do not pose issues for you, the good news is…

If solar power is looked at through a long-term lens, you will eventually make back what you originally spent, and possibly start saving money on your investment. Solar power is not subject supply and demand fluctuations in the way that gas is. Silicon, the primary component of solar panels, is also being more widely produced, therefore, less and less expensive with each passing year. Solar power is independent, or semi-independent. This is great because you can supply your home with electricity during a power outage. Solar power can also be used in remote locations, places where conventional power can’t be reached. On a larger scale, solar power also reduces our need to rely on foreign sources for power. In Pakistan, there are some solar power systems being utilized but together it is less in number in the country just because of the initial cost needed to make larger and bigger and efficient solar power stations so that they can cover a wide area of range for providing power. Let’s hope it comes sooner in our country so that we can get rid of load shedding problem (INSHALLAH). Let’s hope positive!