The control of the quality of irradiation data is often a prerequisite to their further processing. Though data are usually controlled by meteorological offices, the sources are so numerous that the user often faces time-series of measurements containing questionable values. As customers of irradiation data, we established our own procedures to screen time-series of measurements. Since this problem of quality

. Converting a successful research project into a sustainable service: the case of the SoDa web service. Environmental Modelling and Software, Elsevier, 2006, 21, pp

Knowledge of the solar energy resource is essential for the planning and operation of solar energy systems. In past years there has been substantial European and national funding to develop information systems on solar radiation data, leading to the situations that several data bases exist in parallel, developed by different approaches, various spatial and temporal coverages and resolutions including those exploiting satellite data. The user of these products may end up with different results for the same requested sites. To better guide the users, a benchmarking exercise is under preparation. A set of reference data has been collected and benchmarking measures and rules have been defined. The results of the benchmarking and the feedback from stakeholders will be integrated into a guide of best practices in the application of solar resource knowledge. Access to data has been quite fragmented. Each service has its own way of access to the data and delivery format. A new broker portal based on the experience of the project Soda aims to unify and ease the access to distributed data sources and applications providing solar resource information.

The HelioClim-1 database contains daily values of the solar radiation reaching the ground. This GEOSS (Global Earth Observation System of Systems) Data Collection of Open Resources for Everyone (Data-CORE) covers Europe, Africa and the Atlantic Ocean, from 1985 to 2005. It is freely accessible at no cost through the SoDa Service (www.soda-is.com). Several assessments of the HelioClim-1 data against measurements made in meteorological networks reveal that the HelioClim-1 database offers a reliable and accurate knowledge of the solar radiation and its daily, seasonal and annual variations over recent years. The HelioClim-1 data may help in qualifying in situ measurements and may supplement them, thus offering 21 years of accurate daily means of surface solar irradiance. Several published works benefited from openness, availability and accuracy of the He-lioClim-1 database in various domains: oceanography, climate, energy production, life cycle analysis, agriculture, forestry, architecture, health and air quality. This demonstration of the benefit of the HelioClim-1 database draws attention to resources open to everyone such as those labeled GEOSS Data-CORE.

International audienceAssessment of environmental impacts of a power system exploiting a renewable energy needs a large number of geographically-dependent data and of technological data. These data are located in various sources and available in various formats. To avoid the burden of data collection and reformatting, we exploit the interoperability capabilities set up in GEOSS and combine them with other GEOSS-compliant components proposed by projects funded by the European Commission. This is illustrated by the case of photovoltaic systems. A Web-based tool links the various sources of data and executes several models to offer various impacts factors in different areas: human health, climate change, primary energy, ecosystems