In this paper we evaluate the cloud transients by analyzing the dynamics of the direct fraction index kb for one year of solar radiation data in different time steps. We use instant 5-sec data integrated data and compare the number and percentage of occurrences of the different defined sky conditions. We find that the most common situation is a progressive transient and that the average transient lasts between one and 5 minutes. We also perform a cloud transient duration analysis observing that the denser clouds have greater persistence.
Topics
Atmospheric radiation
REFERENCES
1.
Edward W.
Law
, Abhnil A.
Prasad
, Merlinde
Kay
, Robert A.
Taylor
. 2014
Direct normal irradiance forecasting and its application to concentrated solar thermal output forecasting – A review
. Solar Energy
108
, 287
–307
2.
Perez
, R.
, Moore
, K.
, Wilcox
, S.
, Renne
, D.
, Zelenka
, A.
, 2007
. Forecasting solar radiation – preliminary evaluation of an approach based upon the national forecast database
. Solar Energy
81
, 809
–812
.3.
Meyer
, R.
, Beyer
, H.G.
, Fanslau
, J.
, Geuder
, N.
, Hammer
, A.
, Hirsch
, T.
, Hoyer-Click
, C.
, Schmidt
, N.
, Schwandt
, M.
, 2009
. Towards standardization of CSP yield assessments
. In: Proceedings of the SolarPACES Conference
, Berlin (Germany
).4.
Silva-Pérez
, M.A.
, 2002
. Estimación del recurso solar para sistemas termosolares de concentración
. Ph. D. Thesis. University of Seville
.5.
M.
Martínez-Chico
, F.J.
Batlles
, J.L.
Bosch
., 2011
. Cloud classification in a Mediterranean location using radiation data and sky images
. Energy
36
, 4055
–4062
.6.
R.J.
Aguiar
, M.
Collares-Pereira
, J.P.
Conde
., 1998
. Simple procedure for generating sequences of daily radiation values using a library of Markov transition matrices
. Solar Energy
, Volume 40
, Issue 3
, 1988, Pag. 269
–279
.
This content is only available via PDF.
© 2017 Author(s).
2017
Author(s)
