CGIAR SRTM 90m Digital Elevation Data

An alternative SRTM dataset has been developed by the CGIAR consortium for spatial information (CGIAR-CSI). This dataset is also based on the original SRTM dataset published by the U.S. Geological Survey; however it has been post-processed by a number of additional advanced voids filling algorithms as well as utilizing a number of better auxiliary DHM-datasets. Please refer to the CGIAR website for more information on this dataset http://srtm.csi.cgiar.org/.

The spatial coverage of this dataset is the same as for the original SRTM data – as described in the section 2.1 above.

At EMD we have evaluated the differences in the datasets through calculations on three different sites, where all relevant data except the DHM model is replaced. The results are shown in the table below, where the annual energy yields from the proposed wind farms are evaluated. The AEP from the original contour model is set to 100%; these are typically based on data from the local ordinance survey offices. The calculation model used is WindPRO/WAsP.

Table: Annual energy yield on selected wind farm projects using three different digital elevation models.

Site	Original DEM	SRTM v. 3.0	SRTM/CGIAR
Wishek, USA	100%	99.64%	99.64%
Cronalaght, Ireland	100%	99.87%	99.86%
Ometepe, Nicaragua	100%	99.91%	99.77%

Availability in WindPRO

While the data-format privided by CGIAR can be read by WindPRO, then the CGIAR data is not directly available from within WindPRO due to the license conditions.

Use of the CGIAR Data

The CGIAR data has been generated by not-for-profit institutions with the objective of supplying accessible and useful information to developing country organizations. They actively encourage use of these products for scientific purposes. This is not however the case for commercial purposes. The entire dataset is available for commercial use at a modest cost, but permission must be sought. Commercial sectors interested in using this data should contact Dr. Andy Jarvis (a.jarvis@cgiar.org). This dataset should be cited as follows: Jarvis, A., H.I. Reuter, A. Nelson, E. Guevara, 2008, Hole-filled SRTM for the globe Version 4, available from the CGIAR-CSI SRTM 90m Database: http://srtm.csi.cgiar.org.

Due to these license conditions, we currently do not distribute the CGIAR dataset. However, it you meet the requirements; then please visit the CGIAR website.