“Every day, the world produces carbon dioxide that is released to the earth’s atmosphere and which will still be there in one hundred years time.” This carbon dioxide contributes to the “Global Warming Effect” and is one of the numerous reasons, why humankind is looking for alternative energy.
Whereas we used fossil fuels and nuclear power to create energy and thereby destroy our world, we already had an energy source, which in fact exists for over four billion years. In one minute it provides enough energy to supply the world’s energy needs for one year. The talk is about the sun, which is “probably the most important source of renewable energy available today” .
What is Solar Energy and ...view middle of the document...
By means of the three natural ways to transfer heat: conduction, convection, and radiation the solar heat circulates through the building (distribution). To prevent overheating and undercooling additional control elements, like the roof, are included.
The advantage of a passive solar heating system is that, compared to some active solar systems, they do not possess a high initial cost or long payback period. “If properly designed, passive solar buildings are bright and sunny and in tune with the nuances of climate and nature” , which is another advantage as it increases the user comfort.
Nevertheless, this method is not appropriate for every situation and home, as it has some disadvantages. One major drawback “is that heating your home depends entirely on the weather”. Another problem is that using passive solar heating effectively is quite difficult, as it requires precisely configuring parts of your home.
Active Solar Energy Systems
In contradiction to passive solar energy systems, the active ones need external energy sources to power different types of equipment which are used to collect, store and convert solar energy.
Today two main categories of active solar energy systems are in use: thermal and photovoltaic ones.
Solar Thermal Energy Systems
Solar thermal systems concentrate the light to create heat, which is used to heat a working fluid. This fluid could be water, oil, salts, air, nitrogen, helium, etc. If the heated fluid is water, it could be directly stored in a boiler to be used in the household. Otherwise, the heated fluid is used to run an appropriate heat engine like steam engine, gas turbine or Stirling engine, which turns a generator to produce electricity.
This procedure is also used in large solar thermal energy plants, which uses “concentrating parabolic dish systems in large-scale solar fields that concentrate the solar radiation onto a receiver" . In order to concentrate the radiation the systems are tracking the sun, which leads to higher costs. The temperature range of the concentrated energy is about 200 °C to 1000 °C. After the radiation reaches the receiver, it works just like the former introduced system.
As shown in the pictures below, there are different technologies used in such systems. Nevertheless, they all work in the way described earlier.
In contrast to photovoltaic systems, thermal ones are also able to provide electricity during night times, as heat storage is an easy and efficient method. That means “heat can be stored during the day and then converted into electricity at night”. Solar collectors have formed an established norm in the construction industry and are, therefore, offering a high energy contribution at a fairly low cost. Moreover, solar panels can be used in a modular way, which enables users to extend their system whenever needed.
Although there are plenty advantages the system still depends on seasonal and environmental conditions. In addition to that such systems are...