Solar mapping and monitoring

Project description

Title: Solar mapping and monitoring (SolMap)
Commissioned by: German Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety (BMUB)
Country: India
Lead executing agency: Ministry of New and Renewable Energy (MNRE), Government of India
Overall term: 2010 to 2015


In 2010, India launched its National Solar Mission, which is one of the major initiatives worldwide to promote solar energy. The Mission provides a policy framework that includes regulatory measures as well as financial and fiscal incentives for the deployment of solar systems which generate grid-quality power while meeting electricity and heat needs in off-grid mode. The aim of the Mission is to establish 20,000 MW of grid-connected solar power by 2022, while also running 2,000 MW-equivalent of off-grid applications and gradually increasing the solar thermal collector area to 20 million sq m. The availability of reliable and accurate solar radiation data is crucial to achieving these targets. Similarly, it is also important that project developers, operators and investors can evaluate the real life performance of the solar plants commissioned under the scheme.


A system has been established for collecting weather information and comprehensive data on solar radiation, for the preparation of solar maps of India. A benchmarking system has been developed and tested for use in the performance monitoring of solar power plants.


The project supports the Ministry of New and Renewable Energy (MNRE) in establishing a network of solar radiation data monitoring units around India, as part of the countrywide Solar Radiation Resource Assessment (SRRA). The units measure solar and other relevant meteorological parameters. These measurements will be combined with satellite-derived data in order to create maps to provide a better overview of all the country’s solar resources. To this end, the project is using exchanges and cooperation between relevant institutions and experts to transfer German experience and know-how in the field of solar resource assessment.

GIZ is supporting the Centre for Wind Energy Technology (C-WET) in the development of an accurate and enhanced-value database for information on solar radiation and other weather parameters. Such a database is essential for establishing a national solar radiation atlas.

The project will also introduce a mechanism for the systematic evaluation and benchmarking of the technical performance of large grid-connected PV plants. A benchmarking scheme is being launched that will enable an easy overview of the performance of solar power plants in different climatic zones, using different technologies, tracking options etc. In this way, a substantial knowledge pool will develop, with which to estimate yields under real operating conditions, during the planning stage.


  • 117 solar radiation measuring stations have been set up by MNRE/C-WET with support from GIZ. This is the world’s largest pyrheliometric measurement network with high precision data logging.
    Sophisticated procedures have been introduced for the quality control, processing and dissemination of data. Quality controlled time series data streams have been generated for all the measuring stations, and monthly reports are now published.
  • The Solar Data Sharing and Accessibility Policy (2013) of MNRE is now in place. Data products have been made available to the public, and these are being used increasingly by the solar power industry. By the end of 2014, almost 230 such solar data products had been procured by the users.
  • Four typical meteorological years (TMY) have been established by combining data gained from the SRRA with satellite-based models.
  • Four advanced monitoring stations have been set up, with facilities to measure aerosol optical depth, long-wave radiation, albedo levels and other more specialised parameters.
  • A procedure has been developed for PV performance benchmarking.
  • A benchmarking exercise has begun, using performance data taken from several PV plants. These are located across 12 of India’s federal states and, at the outset of 2014, comprised approximately 25% of the country’s total grid-connected PV capacity. A working PV benchmarking analysis tool has been demonstrated.
  • The PV performance benchmarking exercise is now being extended to ensure a more robust analytical dimension. The data from the plants will be subjected to quality controls and several advanced analyses will be carried out.

The outcomes of the project have so far been published in more than ten peer-reviewed academic journals and professional global conferences proceedings.