Data provided by Global Solar Atlas
The Global Solar Atlas (“Atlas") supports solar power development in the phases of exploration, prospection, site selection and pre-feasibility evaluation.
The Atlas provides long-term averages of solar resource (global, diffuse and direct normal), the principal climate phenomena that determines solar power generation. Understanding solar resource is crucial for the development of solar energy applications. In particular for the solar power sector, Photovoltaic (PV) technologies typically require an analysis on Global Horizontal Irradiation (GHI) and Global Tilted Irradiation (GTI, i.e. solar radiation received by the surface of photovoltaic modules). On the other hand, solar thermal energy technologies, such as Concentrated Solar Power (CSP) and Concentrated Photovoltaics (CPV), rely on Direct Normal Irradiation (DNI). Air temperature (TEMP) is also shown as it is the second most important climate variable determining the performance efficiency of solar power systems. Terrain elevation, relative to the sea level (ELE), also determines the choice of a site and performance of the solar energy system.
Photovoltaics (PV) is the most widely applied and also most versatile technology. Therefore this Atlas shows an indicative estimate of yearly average PV power generation values for three types of PV system: (i) small residential rooftop, (ii) distributed, or medium-size commercial roof-mounted system, and (iii) large or utility-scale PV power plant. The PV electricity simulation algorithm, incorporated in the Atlas, provides an approximate estimate of the potential photovoltaic energy (PVOUT), which can be produced at any location covered by the interactive map.
The data, maps and software simulation tool are developed by Solargis.
Data requirements for the stages of a solar power project lifecycle
This Atlas supports only the first stage of a solar energy project lifecycle: prospection and preliminary assessment. High-quality solar resource and meteorological data are needed also in the next stages: (i) project development; (ii) monitoring and asset management; and (iii) forecasting and operational management of solar power plants.
In the stage of project development, site-specific hourly and/or sub-hourly time series and Typical Meteorological Year (TMY) data are required for the technical design, engineering, financing, risk assessment, and due-diligence. Such data is typically generated from at least 10 years or more of continuous climate records at sub-hourly time resolution.
For the phase of regular performance monitoring, quality control, and asset management, high-resolution time series data is used that are measured or calculated by models in real time and regularly delivered to the user.
Different solar power forecasting models offer data for future time horizons, from the hour ahead up to 10 days. Forecasting is required for technical and financial optimization of the operation of individual PV power plants, for energy markets, and for the management of large fleets of PV power systems at the utility scale.
The data, maps and expert studies for these stages, at a global scale, are provided as professional services by Solargis and other suppliers. To acquire high accuracy data, especially for larger solar power plants, solar measuring stations combined with expert analysis are needed. The highest accuracy for solar resource assessment can be achieved by combining modeled and measured data, and carrying out a subsequent validation. Further details on carrying out country-level renewable energy resource assessment studies, including solar, can be obtained from the ESMAP publication, “Assessing and Mapping Renewable Energy Resources” (2016).