hydrogen production from water using solar cells powered nafion ...

Table 1.1. Turkey`s energy usage as a function of the energy sources (WEB_2 2007).
Oil
Mton
Natural
Gas
(10 9 m 3 )
Coal (Mton)
Lignite Hard coal
Hydro
electric
(TWh)
SUM of
Mton oil
equivalence
Consumption 30.0 19.9 56.5 19.4 39.6 91.5
Production 2.28 0.7 55.3 2.2 39.6 25.2
In addition to the limited supply and related cost problems of the fossil fuels, the
atmospheric CO2 concentration has been increasing due to increasing fossil fuel
consumption. It has been agreed by the scientific community that there is a correlation
between the average atmospheric temperature of the world and the atmospheric
concentration of CO2 and has been found that the average atmospheric temperature is
increasing with CO2 concentration (Shi 2003). In fact, not only CO2 but also the other gases
with long atmospheric duration, such as methane, nitrous oxide and some fluorocarbons,
cause greenhouse effect. The greenhouse effect is that the shorter-wavelength solar
radiation emitted from the sun passes through atmosphere and causes earth to warm while a
part of the absorbed radiation is reradiated back to the space through the atmosphere as
long wave radiation but this long wavelength radiation is absorbed by greenhouses gases
such as CO2 in the atmosphere and reemitted to Earth; hence causing the lower atmosphere
warmer. To stop the global warming, an international protocol called “Kyoto protocol” was
accepted by many countries in 1997 to decrease the concentrations of the greenhouse gases
in the atmosphere. Up until now, 169 countries (except United States and Australia) which
are emitting 61.6% of greenhouse gases have accepted the Kyoto protocol. The countries
who signed Kyoto protocol must decrease their CO2 emission within the time period
decided by the committee. In other words, the governments of these countries are supposed
to produce power by emitting less greenhouse gases than the level that they emit now using
either improved energy conversion technologies or alternative fuels with the current
conversion technologies. Efforts have been towards using renewable energy sources, such
as solar, wind, biomass and geothermal energies. Examples for the renewable resource
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