Solar energy in progress and future research trends

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 are then drawn for the solar irradiation ratios as

Fig. 21. Triple solar radiation estimation.

dependent variable. Both solar irradiation and sunshine duration ratios vary between 0 and 1, because they are expressed as ratios to astronomical solar irradiation amounts during cloudless and without atmospheric chemical com­ponents, i. e. with clear and ideal atmosphere situations. It is known that astronomical solar irradiation and sunshine duration values are the maximum ideal quantities ever possible, but the natural counterparts are smaller than these values. In a way, all the TSIE graphs are dimensionless and rather standard with solar irradiation variable values confined to 0-1 interval. The contour lines of solar irradiation might be drawn at each 0.2 intervals. A representative TSIE graph is presented in Fig. 21. The following general interpretations can be drawn from such a graph.

1. variation of solar irradiation with joint variation of sunshine duration and humidity,

2. solar irradiation variation with sunshine duration for any given level of relative humidity,

3. solar irradiation variation with relative humidity for any given level of sunshine duration value,

4. solar irradiation maximal occurrences at relative humid­ity and sunshine duration values,

5. variation of solar irradiation for any combination of sunshine and relative humidity combination,

6. nearly clear weather condition depiction based on sunshine duration and relative humidity values,

7. nearly overcast weather condition depiction based on sunshine duration and relative humidity values,

8. average and standard deviation values of solar irradiation for given ranges of relative humidity and sunshine duration, and hence, it is possible to obtain the arithmetical average and standard deviation variations of solar irradiation by sunshine duration and relative humidity values. This is very helpful in deciding the error limitations concerning upper and lower boundaries in any solar irradiation estimation, and

9. by making use of the previous step one can obtain estimation of solar irradiation for a given pair of sunshine duration and relative humidity value.

The TSIE graphs may be prepared for different time periods such as hourly, daily, weekly and monthly. Comparison of two or more TSIE graphs at different locations help to identify climatic features. On the other hand, it is possible to extend the concept of TSIE graphs by considering other meteorological variables instead of relative humidity such as temperature or pressure. Hence, it is possible to assess whole the available meteorological variable effects and to derive necessary interpretations for the solar irradiation characteristics at a site.

The TSIE graphs are distinct from the restrictive set of assumptions and readily available for linguistic interpret­ations prior to any quantitative estimation procedure. These graphs help to make preliminary fuzzy logic rule bases.

Solar energy in progress and future research trends

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 …

Как с нами связаться:

тел./факс +38 05235  77193 Бухгалтерия
+38 050 512 11 94 — гл. инженер-менеджер (продажи всего оборудования)

+38 050 457 13 30 — Рашид - продажи новинок
Схема проезда к производственному офису:
Схема проезда к МСД

Оперативная связь

Укажите свой телефон или адрес эл. почты — наш менеджер перезвонит Вам в удобное для Вас время.