The National Institute of Solar Energy (NISE) serves as a key bridge between government, research institutions and industry by providing testing, certification, skill development, resource assessment and technology validation services. It supports innovation, promotes industry standards and helps accelerate the commercial deployment of solar technologies across India.
Talking about the role of solar energy in sustainable development, NISE Director General Dr Mohammad Rihan says that there are many forms of energy that people use, but in modern times electrical energy is synonymous with energy itself. He states that it is definitely the most critical form of energy and that, despite its environmental issues, one cannot deny that electricity is a fundamental requirement. He explains that while people describe the present era as a digital society, the oxygen for that society is actually electricity. He notes that this is reflected in the country’s electricity infrastructure and points out that, from less than 100 gigawatts in the late 1990s, India has crossed 500 gigawatts of installed capacity, which is expected to increase by around five times by 2047 or 2050. He says that reliable electricity supply is essential for moving up the development ladder.
He emphasises that access to reliable electricity is a fundamental requirement and must be available to all citizens. However, environmental concerns associated with conventional electricity generation, which is largely based on coal, require solutions that can meet electricity demand without harming the environment.
According to him, several efforts are needed, beginning with electricity conservation and energy efficiency and, of course, shifting generation towards clean energy sources such as solar power. He describes solar energy as a fundamental technology and tool for meeting electricity requirements in an environmentally friendly manner.
Reflecting on the growth of the sector, he says that if one goes back 10 years, solar energy adoption was still in what he describes as an experimental or pilot phase, with people exploring whether the technology could be deployed at scale and what role it could play. However, the progress achieved over the last 10 to 12 years has been outstanding and phenomenal. According to him, there are no parallels in the electric power industry for the way solar has grown in the country. He notes that in 2011 there were only around 10 megawatts of solar capacity in the entire country and that in 2014 capacity remained below 3 gigawatts.
He notes that India has recently crossed 150 gigawatts of solar installations. In the last financial year alone, around 54 to 55 gigawatts of renewable energy capacity were added, of which more than 44 gigawatts came from solar. He highlights that over 44 gigawatts of solar capacity were added in just one year, compared with less than 30 gigawatts in the previous year. He points to the rise from 10 megawatts in 2011, or less than 3 gigawatts in 2014, to more than 150 gigawatts today. He adds that electricity consumption records have been broken almost daily in recent days and that solar’s contribution on these high-demand days has exceeded 20 per cent of electricity supply, describing it as phenomenal growth.
Apart from capacity addition, he highlights that the country is also progressing towards self-sufficiency. Module manufacturing was almost non-existent earlier, but over the last three to five years officially listed manufacturing capacity has reached nearly 175 gigawatts. Cell manufacturing capacity has crossed 30 gigawatts and the country is now moving further down the value chain into ingot, wafer and polysilicon manufacturing.
Turning to another important aspect of solar energy, he argues that the best utilisation of the technology lies in decentralised deployment. He describes solar as a perfectly modular technology. A 1-kilowatt system requires only two or three modules, while a gigawatt-scale plant uses the same modules, simply in much larger numbers. This characteristic makes decentralised deployment possible and, perhaps for the first time in history, apart from diesel generators, which have environmental drawbacks, electricity can be generated directly at the point of consumption.
Within the last year alone, around 16 gigawatts of distributed renewable energy solar capacity have been added in the country, including 7 to 8 gigawatts of rooftop solar under PM Surya Ghar and another 7 to 8 gigawatts under PM-KUSUM.
Discussing how NISE is driving solar growth, he says that as the country undergoes what he describes as a radical transformation, or the solarisation of the power sector, NISE has an important and central role to play. He categorises this role into four or five broad areas.
One of NISE’s primary mandates, he explains, is to support the Ministry in technical matters. NISE is the implementing agency for the Approved List of Models and Manufacturers (ALMM), which is linked to self-reliance in photovoltaic manufacturing. It is also the technical support agency for the PLI scheme for high-efficiency modules. Furthermore, it provides technical support to PM Surya Ghar, PM-KUSUM and several components of the National Green Hydrogen Mission.
He further notes that NISE implements the Ministry’s flagship capacity-building programme, Suryamitra, which forms part of its direct technical support to the government.
As a research and technical institution, he says NISE works on several important research questions. These include module reliability in field conditions, annual degradation, development of high-efficiency modules and perovskite-based technologies. The institute is also exploring new applications such as solarisation of highways, fishermen’s boats, building-integrated photovoltaics and agro-photovoltaics. He adds that NISE works closely with industry on these issues and has recently established a start-up incubation centre.
Testing, standardisation and certification, he says, are critical for creating credible solar infrastructure in the country and NISE actively performs this role. He highlights that NISE has recently established India’s first PV module reference calibration facility and is also working closely with the Bureau of Indian Standards.
He further points out that trained manpower is required across installation, manufacturing, operations and maintenance, testing and research. Therefore, NISE focuses heavily on training and education. The institute has recently launched several advanced postgraduate programmes jointly with universities and technical institutions. One such programme, developed with the National Power Training Institute (NPTI), involves six months of study on grid concepts followed by six months focused on grid integration and renewable energy issues. In this way, NISE contributes through research and development, testing and capacity building.
In addition, the institute works closely with industry and state governments, providing consultancy and technical assistance to strengthen and expand the solar ecosystem across the country.
Turning to grid integration, he explains that solar power plants operate either as off-grid or grid-connected systems, with the vast majority functioning in grid-connected mode. When referring to the increase from 10 megawatts to over 150 gigawatts, most of that growth has come through grid-connected installations.
Recent developments, he says, demonstrate the success of solar integration. When electricity demand exceeds 270 gigawatts, solar contributes between 20 and 22 per cent of total supply. This shows that substantial solar integration has already taken place. Among the key initiatives, he highlights the Green Energy Corridor, which helps evacuate power from regions where solar generation is concentrated.
Another important development is the establishment of Renewable Energy Management Centres (REMCs). He notes that 11 REMCs have been created to implement and monitor solar integration with the grid and that these systems continue to be strengthened.
One of the major reasons behind the country’s success, according to him, is the strength of its electricity grid. He describes it as one of the best grids in the world, characterised by geographical diversity, varied consumption patterns and a highly robust structure. This has enabled solar integration to emerge and grow successfully, and it will continue to support future growth.
On financing, he says that while solar projects are capital-intensive, costs have fallen exponentially over the last decade. He attributes this to a stable, focused and consistent policy framework. When the market receives a clear signal about the future direction and that signal remains unchanged, industry responds and economies of scale emerge.
Ambitious targets have also played a significant role. He notes that the country’s initial target of 20 gigawatts by 2022 was subsequently raised to 175 gigawatts of renewable energy, then to 450 gigawatts and later to 500 gigawatts. According to him, this reflects a highly consistent and stable policy approach.
He adds that market innovations such as tariff-based competitive bidding, reverse auctions, financial support mechanisms and improved financing availability have also contributed significantly. These measures have reduced the cost of solar projects and installations while creating and expanding a robust market.
Solar-plus-storage systems are now comparable to, and in many cases cheaper than, thermal power options. However, he acknowledges that the initial capital cost may still discourage individual consumers. Subsidies are available for rooftop solar through both the Centre and state governments, while farmers receive support for solar-powered irrigation. He concludes that the capital-intensive nature of solar has largely been addressed through consistent policy, market mechanisms and industry participation, while targeted support remains available for individuals.
Discussing storage, he says it is frequently highlighted because solar energy is available only during sunshine hours. However, he emphasises that storage is not the only solution to managing variability.
He cites demand-side management as an important complementary approach. Consumers can be encouraged through innovative tariff structures to shift non-essential electricity use from evening hours to daytime periods when solar power is available. Similarly, industries can be incentivised to operate more during daylight hours.
He further explains that modern inverters used in grid-connected solar plants are highly sophisticated components capable of managing several grid-related issues locally. Ongoing work in this area can help stabilise the grid and reduce overall storage requirements, although storage will still remain necessary.
Storage requirements, he explains, can broadly be divided into short-duration and long-duration categories. Short-duration storage is needed to manage the sharp decline in solar generation that occurs after sunset and is expected to address this specific challenge.
For long-duration storage, solutions are required for inter-regional balancing and overall grid stability. One such solution is pumped storage, which is being promoted at scale across the country. He describes the process whereby water is pumped when excess electricity is available and released later to generate electricity, effectively storing energy.
Battery storage technologies are also being actively explored around the world, particularly long-duration storage solutions. Among the technologies attracting attention are flow batteries, which have the potential to provide long-term storage.
Looking ahead, he says that as the energy system evolves, storage services are likely to develop increasingly as market-based services. He gives the example of a distribution company or grid operator requiring two hours of evening support, which a developer could provide through a dedicated storage system. He concludes that more market-linked initiatives and incentives for storage are likely to emerge as the sector continues to evolve.
