This is the continuation of the previous article. For better understanding it is recommended to look through the earlier blog posts.
International Renewable Energy Agency, IRENA
Created in 2009 the organization’s main goal is to develop and support the renewable energy sources utilization. The organization is aimed at providing a free access to the renewable energy sources data for public and for potential power station developers. IRENA was established on the 26-th of January, 2009 in Bonn, Germany, when 75 states signed an IRENA official statute, which entered into force on the 8-th of July, 2010. IRENA is promoting sustainable development, usage of renewable energy and distributes all the obtained knowledge in order to increase the interest rate in this particular field.
Data visualized on the IRENA is taken from different international sources the majority of which belong to NREL and Global Geographic catalogues as Wind resource maps of the Global Atlas, USA bioenergy data, Full Merra dataset, Spanish National Renewable Energy Centre (CENER) - www.cener.com,World Data base on Protected Areas, WDPA http://www.protectedplanet.net/). Wind data visualization sample is provided in the following figure.
Certain generic models used in IRENA are implemented by several software vendors in specific computer file formats As IRENA represents data in raster and vector format (including data provided by NREL), there is a set of specific file formats commonly applied during data representation.
Coverage: specific vector data format developed in 1981 by ArcInfo
coverage format supports multiple physical files (approximately 12) in a single folder
this data format is proprietary, thus there are published specifications allowed and for any change ArcInfo is required
Shape ‘file’: specific vector data format developed in 1993 by ArcView
extensions supported: .shp, .shx, .dbf; shape file data format comprises several physical disk files (3 and more); it is required for all of the files to be present
open-source, thus it is allowed to publish own specifications; commonly used by other vendors
Geodatabase is a specific vector data format created in 2000 by ArcGIS 8.0. Geodatabase supports multiple layers saved in a single file with .mdb extension (similar to MS Access). Geodatabase format is proprietary; being a recently introduced data format, it is commonly referred as the next generation spatial data file format.
Real world is represented either as object view or as field vie. There are certain specifications in object representation. All the objects of the real world are presented in form of entities located in space. Thus a digital form of the entity is referred as an object. Object in vector model has three types: point; line; area.
The same table (entity) is usually represented at different scales using different object types. This is known as multi-representation. Every object is associated with a behavior pattern i.e. objects can change over time.
In the field view objects of the real world have properties varying continuously over space. Thus every site is assigned a value. The field view is ossible to be represented via model. In case of vector model objects are presented as a triangulated irregular network (TIN).
The following map systems are used for data representation:
Google Hybrid Map
Google Satellite Map
Google Street Map
Google Terrain Map
Bing Satellite Map
Bing Street Map
Open Street Map
To be continued.