Silicon-based solar cells Characteristics and production processes ...

Silicon-based solar cells – characteristics and production processes
7. Summary
To sum up the facts on photovoltaics discussed above, one should also consider
the positive and negative aspects of the above method of electric energy production,
from the point of view of the needs and the energy security of the modern
civilization. The most important merits are the non-existing cost of power supply, the
self-operating and long-term work, the possibility of decentralization of the energy
generation process, as well as the difficulty in localizing the PV system, which is
mostly significant in the moment of armed conflict. A negative evaluation can be
supported by such aspects as the day’s and year’s periodicity of the PV system’s
effective operation, as well as the higher costs of the electric energy production as
compared to those offered by the conventional power engineering, although one
should expect the latter to cease to be valid within the next twenty years. Certain
solutions provide the possibility to eliminate the problems connected with the day’s
periodicity of the PV system’s work. One of them is assigning a part of the electric
energy produced by the PV system to supply the process of electrolysis and hydrogen
generation, which, at the time when the PV system is not illuminated, powers the
fuel cell and provides the continuity in the electric energy supply through the hybrid
PV system. The total power of the PV systems currently installed in the world equals
about 69 GW p [8] and it constitutes only less than 2 % of the total capacity of the
world’s existing conventional, wind, water and atomic power stations, which is
estimated for about 3,5 TW. However, taking into account the dynamic growth of the
photovoltaic cell production, which in 2011, exceeded 29 GW p per year, one should
expect a change in the above proportions in favour of the solar power engineering.
Photovoltaics is, at present, an important element of the world’s economy, and its
progress, for many fundamental reasons, will, in the nearest future, be the motor for
a further growth in the economy and the social level, and above all, in the energy
security of the 21-nd century’s societies.
Also in Poland, one can observe paramount perspectives for photovoltaics. The
“feed-in tariffs” system proposed by the Ministry of Economy for the households
open to the production of green energy, which is already being applied in most
European countries, is based on four pillars:
1) Facilitation in the connection and operation of the Renewable Energy Source
(RES) installations,
2) A clear and attractive system of extra payments for the sale of green energy
produced in households,
3) A stable income perspective in the period of over a dozen years,
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