Let’s not waste, but invest and harvest in solar energy
Solar water heaters have been the dominant thermal technology for 40 years and remain widely used due to their efficiency. In fact, solar thermal technology is the most efficient way to heat water, with efficiencies exceeding 50%. It’s important to note that solar photovoltaic cells are not recommended for heating electrical elements or electric heaters because their efficiencies are currently only at 18%.
Jaideep Malaviya, MD, Malaviya Solar Energy Consultancy and Founder & Secretary, Solar Thermal Federation of India (STFI) discusses recent advancements in solar cell technology, highlighting the shift from crystalline to advanced options like PERC technology with 18% efficiency, in an interview with IBT.
Malaviya also touches on diverse solar applications, such as solar water heaters, solar thermal for industrial processes, and cooling solutions for India’s high cooling load. He underscores the role of solar energy in decarbonization and its potential to drive economic growth and job creation.
Image Source: Pexels
IBT: What are the recent advancements in solar cell efficiency and their potential applications?
Jaideep Malaviya: Solar energy, specifically solar photovoltaics, has been in use for almost half a century. However, the past two decades have witnessed a significant revolution in the use of crystalline solar cells. Once the most common type used, polycrystalline solar cells are now considered outdated. As demand for solar energy increased and people recognized its value and potential, there was a need for more generation in a given area. This led to research and development institutes creating different types of technologies. In the early 2000s, Japan and Germany were among the first countries to take up the solar market, leading to a shortage of solar cells and high premium rates for crystalline solar cells. As a result, alternative technologies such as thin films using chemicals like copper indium selenite and copper gallium selenite were developed. Amorphous silicon is also a family of silicon cells that came into existence. However, while there have been many advancements, there is still much to be done in this sector. Ideally, the solar spectrum should absorb around 40% of solar radiation light, with at least 40% solar efficiency. The crystalline cells that were in use had efficiencies ranging from 11% to 15%.
Improving efficiency is critical for better economics, with even a small percentage making a significant difference. Monocrystal silicones are commonly used in the semiconductor industry while Poly is a lower grade version. To meet increasing demand, factories using monocrystalline technology were established, leading to a breakthrough. Researchers, entrepreneurs, and startups worldwide began working on further enhancing efficiency. The latest version of monocell is ZPERC, which increases efficiency by 2%. Monocrystalline technology offers an average efficiency of 16%, which increases to 18% with PERC technology. By adding more layers to the monocrystalline wafer, tandem cells with multiple coatings of different chemical technologies can achieve even higher efficiencies. Labs have recorded up to 28%, and researchers are exploring ultraviolet and infrared light for even higher efficiencies. Solar cell technology is evolving rapidly, with new technologies emerging every three years, such as the Topcon, an enhanced version of monocrystal. As solar energy becomes more economically feasible, it could potentially meet all our electricity needs.
IBT: How do you foresee diversification of solar applications in India beyond electricity generation which includes water heating or industrial processes and cooling?
Jaideep Malaviya: It’s fascinating how the solar photovoltaic industry is expanding into every sector where electricity is needed. Solar energy is becoming more prevalent in commercial, agricultural, and rural areas. People are eager to participate in solar energy development and make the most of it, as there’s a saying that no one can do everything, but everyone can do something. It’s worth noting that solar energy is converted into two forms: direct heat and electrical energy (photons). This is why it’s called photovoltaics. Both forms have their own unique uses, and solar water heaters are also being utilized to heat water.
Solar water heaters have been the dominant thermal technology for 40 years and remain widely used due to their efficiency. In fact, solar thermal technology is the most efficient way to heat water, with efficiencies exceeding 50%. It’s important to note that solar photovoltaic cells are not recommended for heating electrical elements or electric heaters because their efficiencies are currently only at 18%. However, both solar thermal and photovoltaic technologies can contribute to cooling, which is especially important for countries like India with high cooling loads. These technologies are crucial for decarbonization, which is necessary for countries to achieve net zero emissions. India has an abundance of solar radiation, which presents an eternal and plentiful source of energy. Investment in solar technology will generate economic growth, create jobs, and support entrepreneurship and scientific innovation. The future is bright for solar energy.
IBT: How are innovative solutions like floating solar and integrating solar with agriculture to overcome land and resource constraints in solar adoption?
Jaideep Malaviya: 25 years ago, the dream of using solar cells everywhere seemed impossible to many people. However, as an engineer, I knew there was a light at the end of the tunnel and diversified my software project. Now, we have floating solar or “floatovoltaics” and “agrivoltaics” that have multiple applications, including generating power while saving on land usage. Rooftop PV and agri PV are also being used to make maximum use of available land. Floatovoltaics have the added advantage of preventing water evaporation, as demonstrated in India where canals were covered with solar panels to save water and generate power. While there may be a 15-30% higher cost for capex, the amount saved on land makes up for it. Maintenance is required for floatovoltaics, but agrivoltaics is growing exponentially in India and may soon become a real success. India’s positive vibe is attracting a tribe of farmers who may soon have solar panels on their rooftops, just like they have pump sets for irrigating their land. The potential for solar power in India is immense, and addressing these challenges will be crucial to realizing that potential.
IBT: What policies and regulatory frameworks do you believe are essential to achieving the targets that our nation has set? And what role can international collaborations play in this?
Jaideep Malaviya: The International Solar Alliance, initiated by the honourable Prime Minister, Sri Narendra Modi ji, is a prime example of a successful international collaboration project. Regulators have done an exceptional job paying attention to regulatory issues that require attention, however, some sectors still require regulatory intervention. For instance, solar water heaters are the best application for demand-side management and can help reduce peak demand if one million electric geysers are put on during the day. Hence, regulators need to consider this and encourage consumers to opt for solar water heaters by offering incentives such as rebates on electricity bills. This will help distribution companies manage power more effectively and achieve our national target.
Renewable energy is now widely considered to be power generated from sustainable sources. An excellent way to save energy is through a solar water heater, which is as effective as generating electricity. Electrical-based heating is only about 60% efficient, whereas solar thermal can convert 100% of the energy. This also applies to rooftop solar PV. Each state has its own discoms and regulatory framework, with some states being more attractive for renewable energy than others. Unfortunately, some states have the notion that generating less electricity will impact their balance sheet and hinder company growth. We must aim for 100% renewable energy and a net-zero economy by 2070, with India having a target of 2050. It is important to begin implementing solutions today. If rooftop space is limited, we can raise the height of solar panels and create a shaded area underneath, similar to the floatovoltaics of the agri PV. For rural areas, distributed renewable energy systems are necessary to achieve 100% electrification. This is where energy storage systems come into play. There is plenty of room for innovation in this area. The regulatory authorities are doing a fantastic job, but more needs to be done to achieve our goals.
IBT: How do international collaborations and knowledge exchange through organizations like ISES benefit India’s solar sector? And can you share any success stories in this context?
Jaideep Malaviya: I previously mentioned the success story of the International Solar Alliance. It’s crucial to collaborate now instead of waiting, as it may never happen. India is a favoured destination for international collaborations due to its potential for renewable energy and technical expertise. With plenty of sunlight, investing in solar energy is the way to go. Additionally, India’s skilled workforce positions it to be a world production centre with the right policies in place. In the past decade, India’s solar energy growth has caught the attention of international institutions and associations. The Solar World Congress, which will take place from October 31st to November 4th, has elected India as the next venue. This is an excellent opportunity for India to showcase its success in solar energy and attract more investment and job opportunities.
IBT: What are the projections and forecasts for the future of solar energy especially in terms of technology and adoption?
Jaideep Malaviya: As science progresses, technology will continue to evolve. It is essential to exchange knowledge, especially in the Western world, where liberal knowledge sharing is encouraged. Developing countries may not invest as much in research and development due to financial limitations. However, it is time for developed countries to share their evolving technologies. Investing in India would provide significant value for the price paid for R&D. Climate finance companies will need to offer easy financing for these one-time capital investments. International organizations should also invest in R&D in developing countries like India, China, and African countries. Collaboration with institutions and organizations is key to achieving success in technological development. There are plenty of growth opportunities in this area.
IBT: For aspiring professionals in India’s solar industry, what advice would you offer to make a meaningful impact in sustainable energy solutions?
Jaideep Malaviya: If you truly want to see your country thrive, it’s important to be willing to make sacrifices. Our country’s leader has emphasized the need for renewable energy, and it’s up to all of us to work towards that goal 24/7. Of course, your health and well-being should never be compromised, but giving more than 100% effort towards this cause is crucial. Entrepreneurs and startup companies have a huge opportunity to make a positive impact in the energy sector and contribute to India’s future success. It may not be easy, but with hard work and self-belief, you can achieve great success and make a positive impact on our country’s future. Keep in mind that there is a growing demand for energy worldwide. With the right mindset and competitive spirit, success is within reach.
Jaideep N. Malaviya has been a professional in solar energy since 1996 and is the Managing Director of Malaviya Solar Energy Consultancy. He is also the Founder and Secretary of the Solar Thermal Federation of India (STFI), the world’s only association of solar thermal manufacturers. He has over 24 years of experience in the solar energy industry as a Consultant, Researcher and Trainer and presented over 100 papers at Indian and International Conferences.