Poster, 2017, ENG

The analysis of static boundary condition in solar resource assessment by satellite: the role of high-resolution Digital Terrain Model in irradiance downscaling process

Edoardo Geraldi 2; Salvatore Larosa 1; Filomena Romano 1; Angela Cersosimo 1,3; Domenico Cimini 1,4; Francesco Di Paola 1; Donatello Gallucci 1; Sabrina Gentile 1,4; Saverio Teodosio Nilo 1; Elisabetta Ricciardelli 1; Mariassunta Viggiano 1

1 Institute of Methodologies for Environmental Analysis. CNR IMAA. Potenza. Italy 2 Institute of Archeological Heritage - Monuments and Sites. CNR IBAM. Potenza. Italy 3 University of Basilicata. School of Engineering. Potenza. Italy 4 CETEMPS, Department of Physics, University of L'Aquila, L'Aquila, Italy

The morphological characteristics of the ground have a strong influence in solar resource assessment, especially in terrain with complex orography. The use of accurate Digital Model Terrain (DTM) plays a key role in assessing the amount of solar energy that reaches the earth surface. Complex terrain and areas with local micro-climatic characteristics introduces significant intra-cell variations of irradiance compared to satellite-derived measurements affected by limited spatial resolution. This is mainly due to terrain-related effects such as elevation gradient, obstruction and shadowing by horizon (natural or antropic). Influence of terrain features has been already described by several authors (Ruiz-Arias et al, 2010, Bosch et al, 2010). These terrain-related features (elevation, terrain aspect and slope, horizon angles and sky view factor) can be considered as static boundary condition as they do not change in time. In the framework of the SolarCloud project (funded by the Italian Ministry of Economic Development) this activity has the objective to quantify the dowscaling improvement in satellite-derived irradiance at territory scale using DTM rising resolution products. It is acknowledged that surface morphology is just one of the ancillary data in addition to the satellite observations that are needed in order to get more accurate result in the solar energy assessment. For this purpose, we used satellite-derived irradiance processed by AMESIS model (Advanced Model for the Estimation of the Surface Solar Irradiance, Geraldi et al, 2012) at low (3 km) and high resolution (1 km). These data are downscaled using different DTM resolution and compared with ground based stations measurements. The analysis has been developed using R open source software exploiting SRTM3 (Shuttle Radar Topography Mission 3 Arc-Second Global), SRTM1 (respectively with cell size of ~90 m and ~30 m) and higher resolution DTM generated by the local government (with cell size of 20x20 m and 5x5 m). The horizon elevation angle and sky view factor have been computed up to 25 km distance for each grid point and azimuthal angle (at 1 degree resolution). Issues related with computational time have been addressed by implementing into the algorithm a floating window which subdivided the whole study area in subareas with increasing resolution.

4th International Conference on Energy & Meteorology (ICEM) 2017, Bari, 27-29/06/2017

Keywords

solar resource assessment, downscaling, high resolution digital elevation model, irradiance

CNR authors

Nilo Saverio Teodosio, Cersosimo Angela, Gallucci Donatello, Larosa Salvatore, Romano Filomena, Viggiano Mariassunta, Geraldi Edoardo, Cimini Domenico, Di Paola Francesco, Ricciardelli Elisabetta, Gentile Sabrina

CNR institutes

IMAA – Istituto di metodologie per l'analisi ambientale

ID: 390122

Year: 2017

Type: Poster

Creation: 2018-08-21 11:31:49.000

Last update: 2020-09-09 14:23:39.000

External links

OAI-PMH: Dublin Core

OAI-PMH: Mods

OAI-PMH: RDF

External IDs

CNR OAI-PMH: oai:it.cnr:prodotti:390122