Helioclim-3 (HC3) overview

Last update: Oct. 2016

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Type of ressource Online solar radiation satellite-derived database
Access Via the SoDa website (for pay / for free over Feb. 2004-2005) / automatic (for pay)
Parameters All radiation components over a horizontal, fix-tilted, and normal plane
Spatial coverage
= Meteosat (-66° to +66° both in latitude and longitude)
(Click on the image to magnify)
Temporal coverage Feb. 2004 onwards (updated in real time, every 15 min)
Spatial resolution 3 km at Nadir, approx. 5 km in Europe (see illustration above)
Temporal resolution 15 min
Leadtime A few minutes after image reception
Method Heliosat-2
Version version 4 and version 5
Main publication Rigollier et al. 2004 (others: see publications with keyword "HelioClim-3" or "Heliosat-2")
PVsyst compatible Yes




















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  Input Meteosat images

To compute the HelioClim-3 solar radiation database in real time, our two sites (MINES ParisTech - Transvalor) have been supplied with: reception dishes, acquisition chain, computational resources and servers able to generate HelioClim-3 and to fulfill the requests from the users. The two chains are synchronized for an enhanced robustness of the SoDa Service. The model Heliosat-2 processes the images of the third satellite of the Meteosat Second Generation (MSG-3) collected between 3:00 UT to 20:45 UT (72 images) to compute the 15 minute Global Irradiance values over a horizontal plane (GHI).

  What is actually stored in HC3?

The HelioClim-3 database stores the 15 minute GHI values. When the user launch a request, post-processing layers are applied to correct these values, as illustrated by the following picture on HelioClim-3 version 5. Then decomposition models computes the radiation components on the plane orientation as requested.

Illustration: inputs, outputs, and models in HC3v5

The results of the quality assessment of HC3 versus several in-situ measurements have been published in several peer-reviewed articles.

Missing values in HC3: Several slots (or images) are regularly missed, due to internal shortage or interruption of service by Eumetsat. Except is the whole images of a day are missing, this is totally invisible for the users since the images of a day are interpolated if at least one image is available. For you information, the missing slots are available on this page with the corresponding information, if available (missing value in HelioClim: -999). Please note that the field of view is restricted to the pixels belonging to the Earth and for which the elevation angle of the sun above horizon is larger than 12 degrees.

Hypothesis "end of time integration": the date or instant given for each value corresponds to the end of the summarization/time integration. I.e. 24/04/2010 08:00 means that the associated irradiation or irradiance value has been measured between 07:00 and 08:00. This convention addresses the standard recommanded by the WMO (World Meteorological Organisation).

  Outputs and derived services

From this database, several types of services are proposed: time series of radiation values (via an annual subscription or on-request), maps of radiation (on-request), typical meteorological years (on-request), calibration of HC3 data using ground measurements (on-request)...

The FREE version of the HC3 Web service covers Feb. 2004 till end 2006. The HC3 Web service for pay which delivers data for more recent years is accessible via different types of annual subscriptions. The price of the annual subscription depends on several parameters (time step of the data, type of access, plane orientation...), don't hesitate to contact the SoDa support to receive a quotation.

The presentation of the different services is available on the HC3 Web services info page. Output column content for each service is described on this page.

  HelioClim-3 and Digital Elevation Model

Topography impacts the solar radiation values at ground levels in two ways: the variation of the optical path length and the shadowing effect due to the horizon. Indeed, according to the atmospheric layer tickness crossed by sun rays when reaching the ground, the radiation is modulated: the higher the elevation of a point, the narrower the atmospheric optical layer, and finally the higher the radiation. Each HelioClim-3 value is stored using the default elevation database TerrainBase 5' (worlwide database, spatial resolution of 5' of arc, equivalent to approx. 10 km) to be checked.  An altitude correction is applied "on the fly" to take into account the exact height of the point requested by the user, using the SRTM database (Shuttle Radar Topography Mission, available worldwide, 90 m of spatial resolution and 10 m of uncertainty). The user just has to set the altitude to the default "Automatic" option. It is also possible to take into account the shadowing effect due to the far horizon by putting the "Compute Relief Shadows" input option to "TRUE".

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Bibliography HelioClim-3, Heliosat-2, ESRA, Tubidity Linke factor

(In alphabetic order and and reverse chronological order)

Albarelo et al. 2015 Albarelo T., I. Marie Joseph, A. Primerose, F. Seyler, L. Linguet, L. Wald, 2015. "Optimizing the Heliosat-II method for surface solar irradiation estimation with GOES images. Canadian Journal of Remote Sensing", 41, 86-100, 2015, doi: 10.1080/07038992.2015.1040876. Heliosat-2


Bauer 1996 Bauer O., 1996. Les échanges océan-atmosphère dans l'Atlantique subtropical nord-est : apports de Meteosat. Thèse de Doctorat, Université de Nice - Sophia Antipolis, 162 p. Heliosat


Beyer et al. 1997 Beyer H.-G., Czeplak G., Terzenbach U., Wald L., 1997. "Assessment of the method used to construct clearness index maps for the new European solar radiation atlas (ESRA)". Solar Energy, 61, 6, 389-397. doi:10.1016/S0038-092X(97)00084-4 ESRA (clear-sky model and Linke)


Beyer et al. 1996 Beyer H.-G., Costanzo C., Heinemann D., 1996. "Modifications of the Heliosat procedure for irradiance estimates from satellite images". Solar Energy, 56, 3, p. 207-212. Heliosat-2


Blanc et al. 2011 Blanc Ph., Gschwind B., Lefèvre M., Wald L., 2011. "The HelioClim project: Surface solar irradiance data for climate applications" Remote Sensing, 2011, 3, 343-361. doi:10.3390/rs3020343 HelioClim in general


Cano et al. 1986 Cano D., Monget J.-M., Albuisson M., Guillard H., Regas N., Wald L., 1986. "A method for the determination of the global solar radiation from meteorological satellites data" Solar Energy, 37, 1, 31-39. Heliosat

Content: In this publication, Cano et al. recommended to apply the Heliosat-2 method only for the slots when the sun is above 18° of elevation. We decided to slightly descrease this threshold to 12° in our implementation of Heliosat-2 (HelioClim-3).

Cano 1982 Cano D., 1982. "Etude de l'ennuagement par analyse de séquences d'images de satellite. Application à l'évaluation du rayonnement solaire global au sol" Thèse de Doctorat, Ecole nationale supérieure des télécommunications, Paris, France. Heliosat


Cros et al. 2006 Cros S., Albuisson M., Wald L., 2006. "Simulating Meteosat-7 broadband radiances at high temporal resolution using two visible channels of Meteosat-8". Solar Energy, 80, 3, 361-367, doi: 10.1016/j.solener.2005.01.012. Heliosat-2


Cros et al. 2004 Cros S., Lefèvre M., Albuisson M., Wald L., 2004. "From meteorological satellite data to solar radiation climatological products: the HelioClim database". European Geophysical Union, 1st general assembly, Geophysical Research Abstracts, vol. 6, April 2004, EGU04-A-03853. HelioClim


Cros 2004 Cros S., 2004. "Création d'une climatologie du rayonnement solaire incident en ondes courtes à l'aide d'images satellitales (Design of an incident shortwave solar radiation climatology using satellite images)". Thèse de Doctorat en Energetique, Ecole des Mines de Paris, 13 septembre 2004, 157 pages. HelioClim


Cros et al. 2004 Cros S., Albuisson M., Lefèvre M., Rigollier C., Wald L., 2004. "HelioClim: a long-term database on solar radiation for Europe and Africa". In Proceedings of Eurosun 2004, published by PSE GmbH, Freiburg, Germany, pp. (3)916-920, ISBN 3-9809656-4-3. HelioClim


Cros et al. 2004 Cros S., Chriqi R., Albuisson M., Wald L., Dahman Saidi A., Bennouna M., 2004. "Integration of Meteosat-derived data and digital terrain model into a GIS for local atlases of solar radiation". European Geophysical Union, 1st general assembly, Geophysical Research Abstracts, vol. 6, April 2004, EGU04-A-06543. HelioClim


Demarcq 1985 Demarcq H., 1985. "Applications de la télédétection infrarouge et visible en océanographie. Etude de la zone de dilution rhodanienne, observation des zones de production dans le golfe du Lion, et estimation de l'éclairement solaire global en Méditerranée occidentale". Thèse 3ème Cycle, Univ. Aix-Marseille II. Heliosat


Diabaté et al. 2004 Diabate L., Blanc Ph., Wald L., 2004. "Solar radiation climate in Africa". Solar Energy, 76, 733-744. ESRA


Diabaté et al. 2003 Diabaté L., Remund J., Wald L., 2003. "Linke turbidity factors for several sites in Africa". Solar Energy, 75, 2, 111-119. Linke turbidity factor


Diabaté et al. 1995 Diabaté L., Wald L., 1995. "An attempt to estimate the diffuse component of solar radiation on horizontal plane from satellite images", African Journal of Science and Technology, 11, 1, 39-44. Heliosat


Diabaté et al. 1989 Diabaté L., Moussu G., Wald L., 1989. "Description of an operational tool for determining global solar radiation at ground using geostationary satellite images". Solar Energy, 42, 3, 201-207. Heliosat


Diabaté 1989 Diabaté L., 1989. "Détermination du rayonnement solaire à l'aide d'images satellitaires". Thèse de Doctorat en Sciences, Ecole des Mines de Paris, 272 p. Heliosat



Diabaté et al. 1988 Diabaté L., Demarcq H., Michaud-Regas N., Wald L., 1988. "Estimating incident solar radiation at the surface from images of the Earth transmitted by geostationary satellites : the Heliosat Project". International Journal of Solar Energy, 5, 261-278. Heliosat


Espinar et al. 2012 Espinar B., P. Blanc, L. Wald, B. Gschwind, L. Ménard, E. Wey, C. Thomas, L. Saboret, 2012. "HelioClim-3: a near-real time and long-term surface solar irradiance database". Workshop on Remote Sensing Measurements for Renewable Energy, May 2012, Risoe, Denmark. HelioClim-3 v3


Espinar et al. 2009 Espinar, B., Ramírez, L., Polo, J., Zarzalejo, L.F., Wald, L., 2009. "Analysis of the influences of uncertainties in input variables on the outcomes of the Heliosat-2 method". Solar Energy, 83, 1731-1741, 2009, doi:10.1016/j.solener.2009.06.010. Heliosat-2


Geiger et al. 2002 Geiger M., L. Diabaté, L. Ménard, L. Wald, 2002. "A Web service for controlling the quality of global solar irradiation" Solar Energy, Elsevier, vol. 73 (6), pp.475-480 ESRA (Clear sky model and Linke), Quality check


Grüter et al.  1986 Grüter W., Guillard H., Möser W., Monget J.-M., Palz W., Raschke E., Reinhardt R.E., Schwarzmann P., Wald L., 1986. "Determination of solar radiation at ground level from images of the earth transmitted by meteorological satellites, Solar Energy R&D in the European Community, Series F, vol. 4: Solar radiation data from satellite images", D. Reidel Publishing Co. for the Commission of the European Communities, 100 pp. Heliosat (original)


Kasten 1996 Kasten F., 1996. The Linke turbidity factor based on improved values of the integral Rayleigh optical thickness. Solar Energy, 56 (3), 239-244. Linke Turbidity Factor


Lefèvre et al. 2004  Lefèvre M., Cros S., Albuisson M., Wald L., 2004. "Developing a database using Meteosat data for the delivery of solar radiation assessments at ground level". In Proceedings of the 23rd EARSeL Annual Symposium "Remote Sensing in Transition", 2-4 June 2003, Ghent, Belgium, Rudi Goossens editor, Milpress, Rotterdam, Netherlands, pp. 485-489. HelioClim



Lefèvre et al. 2002 Lefèvre M., Rigollier C., Cros S., Wald L., 2002. "Toward a solar climatological database: the HelioClim project". In Proceedings of 22nd EARSeL Annual Symposium "Geoinformation for European-wide integration", 4-6 June 2002, Prague, Czech Republic. Tomas Benes editor, Millpress, Rotterdam, Netherlands, pp. 223-228. HelioClim


Lefèvre et al. 2002 Lefèvre M., Rigollier C., Cros S., Albuisson M., Wald L., 2002. "A shortwave radiation database to support GODAE-related activities". Proceedings of the International Symposium "En route to GODAE", 13-15 June 2002, Biarritz, France. Published by CNES, Toulouse, France, 2002, pp. 157-158. HelioClim


Marie-Joseph et al. 2013 Isabelle Marie-Joseph, Laurent Linguet, Marie-Line Gobinddass, Lucien Wald. "On the applicability of the Heliosat-2 method to assess surface solar irradiance in the Intertropical Convergence Zone, French Guiana". International Journal of Remote Sensing, Taylor & Francis, 2013, 34 (8), pp.3012-3027. <10.1080/01431161.2012.756598> Heliosat-2


Michaud-Regas 1986 Michaud-Regas N., 1986. "Mise en oeuvre et validation d'une méthode opérationnelle et automatique pour l'évaluation d'atlas solaires en Europe à l'aide de mesures satellitaires Meteosat"  Thèse de Doctorat, Univ. Paris VII, Paris, France. Heliosat


Moussu 1988 Moussu G., 1988. "Définition d'une méthodologie de détection de phénomènes dynamiques dans une chronique d'images, et son application à quelques études". Thèse de Doctorat en Sciences, Univ. Nice. Heliosat


Obrecht 1990 Obrecht D., 1990. "Météorologie solaire et images satellitaires : cartographie du rayonnement solaire, détermination de l'albédo des sols et évaluation de l'ennuagement", Thèse de Doctorat en Sciences, Univ. Nice. Heliosat


Page et al. 2001 Page J., Albuisson M., Wald L., 2001. "The European Solar Radiation Atlas: a valuable digital tool". Solar Energy, 71, 81-83, doi:10.1016/S0038-092X(00)00157-2 ESRA (clear-sky model and Linke)


Qu et al. 2014 Qu Z., B. Gschwind, M. Lefevre, and L. Wald, 2014. "Improving HelioClim-3 estimates of surface solar irradiance using the McClear clear-sky model and recent advances in atmosphere composition", Atmos. Meas. Tech., 7, 3927-3933, doi:10.5194/amt-7-3927-2014 (Creative Commons Attribution 3.0 License) HelioClim-3 v3 + McClear


Qu 2013

Qu, Z.: Modeling radiative transfer in cloudy atmosphere to assess surface solar irradiance (in French), Ph.D thesis, MINES ParisTech, 202 p., 2013.

Heliosat, HelioClim


Remund et al. 2003 Remund J., Wald L., Lefèvre M., Ranchin T., Page J, 2003. "Worldwide Linke turbidity information", Proceedings of ISES Solar World Congress, 16-19 June 2003, Göteborg, Sweden. CD-ROM published by International Solar Energy Society.  Linke turbidity factor


Remund et al. 2003 Remund J., Wald L., Page, J., 2003. "Chain of algorithms to calculate advanced radiation parameters". Proceedings of ISES Solar World Congress, 16-19 June 2003, Göteborg, Sweden. HelioClim


Rigollier et al. 2004 Rigollier C., M. Lefèvre, L. Wald, 2004. "The method Heliosat-2 for deriving shortwave solar radiation from satellite images", Solar Energy 77(2), pp. 159-169, 2004, doi 10.1016/j.solener.2004.04.017



Rigollier et al. 2001 The new method HELIOSAT-II. Report 1 to the European Commission, April 2001. (plus some figures in Word file). Report 2, June 2001. Heliosat-2


Rigollier et al. 2000 Rigollier C, Bauer O, Wald L, 2000. "On the clear sky model of the 4th European Solar Radiation Atlas with respect to the Heliosat method", Solar Energy, 68, 1, 33-48. doi: 10.1016/S0038-092X(99)00055-9 ESRA (clear-sky model and Linke)


Rigollier 2000 Rigollier C, 2000. "Vers un accès à une climatologie du rayonnement solaire : estimation de l'irradiation globale à partir d'images satellitales", thèse de Doctorat en Sciences et Technologies de l'Information et de la Communication, Université Nice - Sophia Antipolis, 194 p. Heliosat-2 Heliosat-2


Wald et al. 2011 Wald L., P. Blanc, B. Espinar, B. Gschwind, M. Lefevre, et al. 2011. "Early achievements towards an automatic assessment of the uncertainty in solar irradiation using web services", Pillmann W., Schade S., Smits P. 25th EnviroInfo Conference Environmental Informatics, Oct. 2011, Ispra, Italy. Shaker Verlag, Aachen, Germany, Vol. 1, pp.309-318  HelioClim-3

Comment: Model for the estimation of lower and upper bounds when selecting standard HC3 outputs and horizontal plane orientation (escribed in section 4).

Wald et al. 1992 Wald L., Wald J.-L., Moussu G., 1992. "A technical note on a low-cost high-quality system for the acquisition and digital processing of images of WEFAX type provided by meteorological geostationary satellites", International Journal of Remote Sensing, 13, 5, 911-916. Heliosat

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