Principle & How it works
Photovoltaics, better known as solar cells, convert
energy from the sun’s irradiation into electricity.
Solar cells are packaged in photovoltaic modules, these
modules connected electrically together in parallel or
in series to create a solar photovoltaic array. To
explain the photovoltaic solar panel simply, photons
from sunlight knock electrons into a higher state of
energy, these electrons in turn move to electrical
circuit creating electrical energy.
Solar cells produce direct electrical current, which can
be used to power electrical applications. The solar cell
is made from a thin layer of a semiconducting material.
In over 95 % of cells manufactured, this material is
silicon. It is not an optimum semiconductor but is easy
to work with and cheap due to its abundance and long
experience with the material in the microchip industry.
- Photovoltaics need no fuel for operation
and are a sustainable energy source. There are zero
emissions from electricity generation.
- In arid regions, desert areas can be
exploited. Many of the world’s developing countries,
where demand for electricity is growing rapidly,
provide bright sunlight.
- Solar panels can be made in small modular
units which can be incorporated into buildings.
- When there is extra demand in the summer
for air-conditioning, solar technology can offset
this extra load and match it due to the fact that
the demand for air-conditioning increases with times
of peak sunshine.
- Photovoltaics can provide electricity for
isolated areas where the electricity grid is not
cost-effective to reach.
- Operating and maintenance costs are
- Significant financial incentives in Japan
and then Germany triggered a huge growth in demand,
followed quickly by production.
- All silicon solar cells require extremely
pure silicon, which is expensive, and energy
intensive. Even with new methods, a silicon solar
cell takes 2 years to generate the energy needed to
make it. Solar thermal power plants need around 5
months to get back their energy makeup.
- The selling price of modules is still too
high to compete with grid electricity in most
- Photovoltaic output heavily depends on
length of daily sunlight and intensity. It is not a
stable source of energy because weather changes are
not controllable so times of cloud cover will
unavoidably decrease the amount of generated energy.
Where it's working (Syria, Abroad)
The first practical application of photovoltaics was to
power orbiting satellites and other spacecraft, but
today the majority of photovoltaic modules are used for
grid connected power generation. In this case an
inverter is required to convert the DC to AC. There is a
smaller market for electrification of remote dwellings,
roadside emergency telephones, remote sensing, cathodic
protection of oil pipelines ,solar lighting and water
A single module is enough to power an emergency
telephone, but for a house or a power plant the modules
must be arranged in arrays. A significant market has
emerged in urban locations for solar-power-charged
storage-battery based solutions. These are deployed as
stand-by systems in energy deficient countries like
India and as supplementary systems in developed markets.
In Syria, there have been several projects supported by
the national organizations for electrification of some
rural villages like Abou Sora, Musherfh, Zarzarita and
others. The Scientific Studies and Research Centre
(SSRC) in Aleppo has begun assembling PV modules in 1999
with 250 KWp annual production capacity as well as
manufacturing of controllers for photovoltaic
applications. Furthermore, there are several projects in
solar water pumping , billboard solar lighting and solar
street lighting but all of these projects have limited
expansion around the country.
Future Development & integration
Photovoltaic power certainly will not be
cost-competitive for large-scale applications without
financial incentives. More research is needed to
increase the efficiency of solar cells, decrease their
price per square meter. Many power producers are using
photovolaics to help cover peak loads, rather than
building entirely new plants. Because photovoltaic
technology is so modular in design, these additional
stations can easily grow from year to year, covering
higher and higher loads. Future development includes
Building Integrated Photovoltaics (BIPV), which is one
of the fastest growing segments of the photovoltaic