Primary Uses
- Utility-scale prospecting
- Site assessment
When you are looking at multiple locations, how do you know that you are comparing apples to apples and oranges to oranges? Solar DIF (Diffuse Horizontal Irradiance) GIS layers provide consistent, seamless datasets so you have a clear picture of the opportunities and risks for every potential site in your portfolio.
With 3TIER Solar DIF GIS Data Layers, you can integrate spatial solar resource data directly into your own GIS mapping software for in-depth analysis, including site prospecting, sorting, and optimal selection.
By layering 3TIER Solar or Wind GIS Layers with each other you can get a complete sense of your resource potential. You can also use third-party layers, such as land ownership, population density, soil type, topography, and transmission and transportation infrastructure, to factor in many of the variables that affect the viability of a site. This enables you to identify promising locations more quickly, as well as understand potentially fatal flaws at a proposed site early in your prospecting process.
3TIER offers Solar DIF GIS Layers useful for all solar development projects, which are cost effective and can be quickly delivered. 3TIER was the first to create a high-resolution (approximately 3 km) dataset for solar resource information with near global coverage. Our data layers are designed for wide-scope prospecting and assessment. All datasets are derived from over a decade of high resolution satellite imagery using proven techniques, state-of-the-art satellite processing algorithms, numerical weather prediction (NWP) models, and publicly available observational data.
GIS Data Layers are obtainable for annual or monthly values of DIF (Diffuse Horizontal Irradiance) and are available in several formats to ensure easy data upload into almost any GIS program.
3TIER produced the first global solar irradiance map and time-series dataset at roughly three times the resolution of previous US solar datasets and at thirty times the resolution of global datasets available from NASA. Based on over a decade of satellite imagery and cutting-edge technology, our uniform methodology is supported by a large scientific and research community and results in a consistent map and dataset, enabling more accurate point-to-point comparisons.
The dataset is based on actual, half-hourly, high-resolution visible satellite imagery observations via the broadband visible wavelength channel at a 2 arc minute resolution. These data have been processed to hourly GHI, DNI, and DIF values. 3TIER processes the satellite images based on a combination of in-house research and algorithms published in peer- reviewed scientific literature. These algorithms contain parameters and coefficients that are based on empirical fits to observational data. The specific satellites and length of time varies slightly by region due to differences in the availability of data from region to region. See the chart below for more details.
| Regions | Satellites | Temporal Coverage |
| Western Hemisphere | GOES 8 - 12 | 13 years (January 1997 - December 2009) |
| South Asia and Middle East | Meteosat 5, Meteosat 7 | 10 years (January 1999 – April 2009) |
| East Asia and Oceania | GMS 5, GOES 9, AMTSAT | 10 years (December 1999 – March 2009) |
| Europe and Africa | Meteosat 7, Meteosat 9 | 11 years (July 1998 – June 2009) |
To develop and validate our model, 3TIER used observations from:
Find our validation papers here.
If you are unfamiliar with the technical terminology on this page, please visit our Glossary for more information.
