Marcel Suri

A New GIS-based Solar Radiation Model and Its Application to Photovoltaic Assessments

The solar radiation model r.sun is a flexible and efficient tool for the estimation of solar radiation for clear-sky and overcast atmospheric conditions. In contrast to other models, r.sun considers all relevant input parameters as spatially distributed entities to enable computations for large areas with complex terrain. Conceptually the model is based on equations published in the European Solar Radiation Atlas (ESRA). The r.sun model was applied to estimate the solar potential for photovoltaic systems in Central and Eastern Europe. The overcast radiation was computed from clear-sky values and a clear-sky index. The raster map of the clear-sky index was computed using a multivariate interpolation method to account for terrain effects, with interpolation parameters optimized using a cross-validation technique. The incorporation of terrain data improved the radiation estimates in terms of the models predictive error and the spatial pattern of the model outputs. Comparing the results of r.sun with the ESRA database demonstrates that integration of the solar radiation model and the spatial interpolation tools in a GIS can be especially helpful for data at higher resolutions and in regions with a lack of ground measurements.

Inventory of major landscape changes in the Czech Republic, Hungary, Romania and Slovak Republic 1970s – 1990s

Abstract One of the most important achievements in 1998–1999 of Phare Topic Link on Land Cover has been the development and practical application of a methodological approach to landscape change identification and analysis in the territories of four Phare countries (the Czech Republic, Hungary, Romania, and the Slovak Republic). The changes were identified on a national level from Landsat TM and MSS satellite images by application of the CORINE Land Cover databases for two time horizons (the late 1970s and early 1990s) at the second hierarchic level. Based on identified causality, the landscape changes were grouped into 7 types: intensification of agriculture, extensification of agriculture, urbanisation-industrialisation, enlargement (exhaustion) of natural resources, afforestation, deforestation and other anthropogenic causes. The results of the groupings are presented in the form of contingency tables and maps showing the spatial distribution of the changes. From the point of view of total extent, forest landscape changed the most in the Czech Republic. This change represents a reduction of forest by 167,702 ha and an enlargement of transitional woodland-scrub by about 26,339 ha. In Hungary the most pronounced changes were decrease of forests by 66,622 ha and decrease of arable land, orchards and vineyards by 21,529 ha. The most remarkable changes identified in Romania were decrease of arable land, forests and wetlands by 366,817 ha, 285,887 ha, and 59,967 ha, respectively, as well as enlargement of areas of complex cultivation pattern by almost 347,220 ha. The most pronounced changes in Slovakia were represented by diminution of forest by 94,935 ha and that of heterogeneous agricultural areas by 18,451 ha; enlargement of transitional woodland-scrub areas and urbanised area were about 13,107 ha and 14,990 ha, respectively.

Chapter 2 – Semi-Empirical Satellite Models

This chapter discusses the basic principles of solar-irradiance modeling based on the use of input data from geostationary satellites and atmospheric models. Two operational approaches (SUNY/SolarAnywhere and SolarGIS), which are based on the use of semi-empirical models, are presented in the context of recent developments.

Solar Resource Modelling for Energy Applications

Solar energy is the main driver of natural processes on the Earth surface. It is an important input parameter into environmental, ecological and risksimulation models as the energy budget at the land surface and depends on the terrain. Vegetation biodiversity, and biomass production are also related to the radiation input.

Optimisation of Interpolation Parameters Using Cross-validation

Quality of data used in the GIS-support tools is a critical issue, as the decisions that affect locations or areas are to be made effectively, in time and with adequate accuracy. At present, a number of European Union and national policy strategies rely on the use of quality digital elevation model (DEM) data. The accuracy, smoothness and representativeness are properties of DEM determining outputs of the support systems that are designed for assessment of renewable energy resources, flood forecasting, disaster and security management. Similarly, suitability analysis, calculating of environmental indicators and water quality monitoring within the catchments are based on the use of DEM and the decisions taken have financial and legal implications. Thus, a prerequisite for full exploitation of the potential of DEMs is to make them available for the community at sufficient accuracy and detail for a variety of applications.

Site-adaptation of satellite-based DNI and GHI time series: Overview and SolarGIS approach

Site adaptation is an approach of reducing uncertainty in the satellite-based longterm estimates of solar radiation by combining them with short-term high-accuracy measurements at a project site. We inventory the existing approaches and introduce the SolarGIS method that is optimized for providing bankable data for energy simulation in Concentrating Solar Power. We also indicate the achievable uncertainty of SolarGIS model outputs based on site-adaptation of projects executed in various geographical conditions.

Towards Designing an Integrated Earth Observation System for the Provision of Solar Energy Resource and Assessment

The GEOSS strategic plan specifically targets the area of improved energy resource management due to the importance of these to the economic and social viability of every nation of the world. With the worlds increasing demand for energy resources, the need for new alternative energy resources grows. This paper overviews a new initiative within the International Energy Agency that addresses needs to better manage and develop solar energy resources worldwide. The goal is to provide the solar energy industry, the electricity sector, governments, and renewable energy organizations and institutions with the most suitable and accurate information of the solar radiation resources at the Earths surface in easily-accessible formats and understandable quality metrics. The scope of solar resource assessment information includes historic data sets and currently derived data products using satellite imagery and other means. Thus, this new task will address the needs of the solar energy sector while at the same time will serve as a model that satisfies GEOSS objectives and goals.

Challenges to Realise 1% Electricity from Photovoltaic Solar Systems in the European Union by 2020

Accumulated installations of photovoltaic solar systems in the European Union have reached almost 2 GW at the end of 2005. The generated electricity was in the range of 2 to 2.5 TWh or merely 0.8% of the 3000 TWh consumed in 2005. Standard models predict an average yearly growth of electricity consumption in Europe of 1.3% until 2020. The European Photovoltaic Industry Association Roadmap aims for a total installed capacity of 41 GW photovoltaic solar systems or an electricity generation in the range of 49 TWh or 1.1%. To reach the 41 GW in 2020 a continuous annual growth of 30% for 15 years is necessary. If we assume, that 50% of this 41 GW will be installed in two Solar I regions in Europe (Southern Italy and Southern Spain), this can correspond to 50% or more in those geographic areas at certain times of the day and distribution problems of this electricity are not addressed yet