Sky-Diffuse radiation models for the globe
Metadatos
Mostrar el registro completo del ítemEditorial
Universidad de Granada
Departamento
Universidad de Granada. Departamento de Ingeniería de la Construcción y Proyectos de IngenieríaMateria
Radiación solar Tierra Recursos energéticos Energía solar Desarrollo sostenible Análisis de regresión
Materia UDC
72 6201
Fecha
2017Fecha lectura
2017-09-18Referencia bibliográfica
Etxebarria Berrizbeitia, S. Sky-Diffuse radiation models for the globe. Granada: Universidad de Granada, 2017. [http://hdl.handle.net/10481/48219]
Patrocinador
Tesis Univ. Granada. Programa Oficial de Doctorado en Ingeniería Civil y ArquitecturaResumen
The increase of greenhouse gases concentration in the atmosphere causes the climate
change and global warming. The excessive use of fossil fuels is the most relevant cause of
this phenomenom. The emissions related to the burning of these fuels are concentrating in
the atmosphere and leading to the warming of the Earth. Apart from the hazardous effects
of the utilization of fossil fuels, it is important to note that their reserves are finite, and the
enormous consumption of oil, gas and coal in the last 200 years has led to their depletion.
Renewable energy sources, also known as alternative or green energy sources, are
naturally replenished, clean and environmental friendly with zero or almost zero emissions
of greenhouse gases and pollutants. They have the potential to meet the worldwide
current and future energy demand. The solar energy is the most promising green energy
source.
For a proper design of solar energy application systems, it is essential to have solar
radiation data. The starting point for the radiation data is almost always global and diffuse
horizontal radiation in the form of hourly or sub-hourly data. It is not always possible to
obtain a long-term series of hourly or sub-hourly data for the above-mentioned parameters.
Global radiation at an hourly, daily or monthly frequency is the most commonly measured
solar data and this is available for a limited number of stations. The measurement of the
diffuse radiation is even scarcer due to higher operational costs associated to the
measurements and meteorological offices tend to record the latter variable at much fewer
locations.
On the contrary, through the work of NASA (http://eosweb.larc.nasa.gov/cgibin/
sse/retscreen.cgi?email=rets@nrcan.gc.ca) it is now possible to obtain daily-averaged
irradiation data for virtually any location in the world. These data include long-term
estimates of meteorological quantities and surface solar energy fluxes obtained from
satellite systems.
Using established models, it is then possible to decompose the daily to averaged-hourly
global irradiation. The missing link so far has been hourly averaged diffuse irradiation. In
this study data was pooled from 19 world-wide locations to obtain a regression model to
complete the above missing link. It was presently shown that the averaged–data
regressions are distinctly different from previously available hour-by-hour regressions.