Spatial solar radiation estimation
In the previous sections, the modeling of solar radiation is discussed on a given site. However, in practical solar energy assessment studies, it is also necessary to have spatial (multiple …
Solar thermal collectors and applications
Extensive fossil fuel consumption in almost all human activities led to some undesirable phenomena such as atmospheric and environmental pollutions, which have not been experienced before in known human history. …
Heat transfer and losses
As explained earlier the easiest way of solar radiation collection is for low temperature heating purposes. It is well known that black surfaces absorb solar radiation more than any other …
Topographic effects
90* 60' 50" 40' 30* 20* 10* N 0* S 10* 20* 30* 40" 50*60* 90 Topography is the expression of the earth’s surface directional vision, height and surface features …
Linear interpolation
The essence of the spatial interpolation is to transfer available information in the form of data from a number of adjacent irregular sites to the estimation site through a function …
Natural energy sources
All types of energy, renewable or non-renewable, can be traced back to either atmospheric activities in the past or to the present and future activities within the atmosphere. The renewable …
Conduction
It is the heat transfer within a solid body where there are at least two different heat areas, i. e. temperature difference. Such a heat transfer is possible by means …
Astronomic effects
Sun releases energy continuously by a fusion reaction that produces 3.94 X 1023 kW of power. This is the main source astronomically available in the sun, but it has to …
Standard weighting function
It is said in the previous subsection that all the classical weighting functions appear as a non-increasing function with distance. It is, therefore, logical to execute the following steps in …
Energy units
In general, energy is defined as the ability to perform work. According to the first law of thermodynamics, the total sum of all energy forms in a closed system is …
Radiation
A hot body may lose heat by radiation through emission of electromagnetic waves The maximum power which can be radiated from a body at a given temperature is called the …
Solar radiation and heat models
Long-term surface solar radiation records have been kept at only a few sites worldwide [98]. Solar radiation is conceptually simple and its attenuation through the atmosphere can be modeled with …
Solar radiation devices and collectors
The solar radiation can be used principally as a source of heat, particularly in the forms of domestic hot water consumption, crop dying, power heat engines, power for refrigerators and …
Energy and population
The two major reasons for the increase in the energy consumption at all times are the steady population increase and strive for better social and economical developments. The world population …
Future expectations
In general, there are two distinctive reasons for future energy researches. First, as a result of global warming, atmospheric and environmental pollutions due to energy consumption, present day energy pattern, …
Linear models
The most widely used equation relating radiation to sunshine duration is the Angstrom-Prescott relationship, which can be expressed as [5,116]:where N is the total number of daylight hours in the …
Flat plate collectors
In order to design a solar energy powered device, it is necessary to know how the power density will vary during the day at the site concerned seasonally. It is …
Renewable alternatives
The sun is the primary source for new and renewable energy alternatives. Unfortunately, this source is not consumed sufficiently at its full extent everywhere in the world. This is due …
Non-linear models. modification of the Angstrom equation with two six-month seasons, namely, October-March and April-September periods leading to two different linear models as
^ = 0.18 + 0.60 S (37) H0 S0 and H S — = 0.24 + 0.53 — (38) H0 S0 respectively. It is to be noticed that although the …
Concentrating (focusing) collectors
Logically, in order to collect the maximum radiation for each unit surface area of the collector, it is necessary to direct its surface at right angles to direct radiation direction …
Solar energy alternatives
The nuclear fusion reactions in the sun yield a huge amount of energy, which is estimated at 3.47 X 1024 kJ per unit time. Only a small part of about …
Unrestricted model
An alternative unrestricted method (UM) is proposed by §en [128] for preserving the means and variances of the global irradiation and the sunshine duration data. In the restrictive regression approach …
Photo-voltaic
The term ‘photovoltaic’ is derived by combining the Greek word for light, photos, with volt, the name of the unit of electromotive force. The discovery of the photovoltaic effect is …
Sun radiation
Earth receives virtually all of its energy from space in the form of solar electromagnetic radiation. Its total heat content does not change significantly with time, indicatinga close overall balance …
Power solar radiation model
As explained above, there are many effects, which render the relationship between the solar terrestrial irradiation and the sunshine duration data into a nonlinear character This physical basis poses questions …
Photo-optical collection and transmission of solar energy
The need for new and renewable energy alternatives due to the depletion of conservative energy sources brought along also the studies on the efficient usage and transmission of available energies. …
Environmental prospects
It has been stated by Dunn [35] that several problems have arisen from the increased use of energy. For example, oil spillages result from the tanker transportations. Burning of various …
Solar irradiation polygon model
Classical approaches based on Angstrom equation for expressing the solar global irradiation in terms of sunshine durations are abundant in the literature. As already explained above, all of them include …
Solar-hydrogen power
The world energy demand depends mainly on fossil fuels with respective shares of petroleum, coal and natural gas at 38, 30 and 20%, respectively. The remaining 12% are filled by …
Solar irradiation calculation
After the solar radiation enters the earth’s atmosphere, it is partially scattered and partially absorbed. The scattered portion is also called as the diffuse radiation, which goes partially back to …
Triple solar irradiation estimation model
In the triple solar irradiation estimation (TSIE) procedure the vertical Cartesian axis is allocated for sunshine duration ratio and the horizontal axis is for the relative humidity. The contour lines …
Hydrogen storage and transport
Any discrepancy between the energy supply and demand can be offset by hydrogen storage, and its use at the time of need as a source of energy. Hydrogen can be …
Meteorological effects
In the past, there has been claims that all weather and climate changes are caused by variations in the solar irradiance countered at other times by the assertion that these …
Fuzzy-genetic solar irradiation models
Terrestrial solar irradiation estimations are obtained mostly from the sunshine duration measurements through almost linear models such as the classical Angstrom formulation (Eq. (36)). The parameters of such models are …
Research and development needs
Industrial countries consider hydrogen as environmentally clean energy source hydrogen. In order to make further developments in the environmentally friendly solar-hydrogen energy source enhancement and research, the following main points …