- Rooftop solar has significant potential in India but growth in the sector has lagged due to many factors including a focus on mega solar power projects.
- India has a target of achieving 40 gigawatts (GW) of green energy from the rooftop solar sector by 2022 but it has not been able to achieve even 20 percent from it so far.
- Conservationists have often highlighted rooftop solar as an alternative to large-scale renewable energy projects that come with several ecological and social costs.
- Scientists emphasise that it is also more economically viable than large-scale utility projects. They call for a policy shift from centralised to decentralised projects and focus on commercial and industrial rooftop solar to boost the growth in the sector.
As India is inching closer to 2022, it increasingly becomes clear that achieving an installed capacity of 40-gigawatts (GW) from the rooftop solar sector by 2022 is nearly impossible.
Envisaged in 2015, the 40 GW target was part of the 175 GW of renewable energy plan that India aimed to achieve by 2022. The plan was later ramped up to 450 GW by 2030 but in both scenarios, the lion’s share is planned from large-scale solar power projects.
India has recently achieved the installed capacity of 100 GW of renewable power but the majority of that – about 78 percent – is due to large-scale wind and solar power projects. This is when scientists and conservationists have often highlighted rooftop solar as an alternative to large-scale renewable energy projects that come with several ecological and social costs. So far (till July 2021), the country has been able to achieve about 5.1 GW of rooftop solar.
In fact, the large-scale renewable power projects have been facing stiff resistance from the communities losing land to them.
Large solar farms often require a lot of water to keep the panels well-maintained. In places where water is a precious commodity such as Rajasthan, this is a concern said Debajit Palit, Director of The Energy and Resources Institute’s Rural Energy and Livelihoods programme.
Apart from these environmental and social issues that surround the placement of renewable energy projects, ecological concerns are many too. Ground-mounted solar panels, for instance, mean that any existing vegetation can be lost, endangering local wildlife both big and small. And some habitats are more at risk than others. One stark example is that of the great Indian bustard, whose habitat in Rajasthan is facing threat due to renewable energy projects.
“The big issue is for habitats that are classified incorrectly,” said Nitin Pandit, chief executive officer of the Ashoka Trust for Research in Ecology and the Environment, Bengaluru.
Such as ‘wastelands’, he said, a term from the 1970s and a vestige of India’s colonial past that includes many of the country’s pristine grasslands and scrublands. But these are ecologically precious systems that in fact pre-date forests in India; calling them ‘wastelands’, therefore, is “willful ignorance” on the part of the government because we have known for long that it is “substantially wrong”, he added.
The “National Wastelands Atlas of India” lists the status of such ‘wastelands’ across India’s states. According to its latest 2019 report, around 8,400 square kilometres of the area have been brought to “non-wastelands class” from 2008-09 to 2015-16. But experts note that such areas often include grasslands and savannas, and a lot of India’s semi-arid Open Natural Ecosystems (ONEs).
The preprint of a new study that mapped India’s semi-arid Open Natural Ecosystems (ONEs) finds that less than five percent of ONEs are covered under the existing protected area network of India though they cover around 300,000 square kilometres (or 10 percent) of India’s land area. “…one of the biggest threats to ONE in recent years stems ironically from India’s global leadership role in the large-scale deployment of renewable energy technologies such as grid-scale solar farms,” write the authors in the paper. Their map “thus provides an important layer for planners to incorporate within existing frameworks that prioritise climate change mitigation through tree restoration, or in energy and development planning,” the study suggests.
Rooftop solar’s potential and challenges
The alternative that many conservationists suggest India focus on, rooftop solar, started with phenomenal growth in its early years. According to a report on the rooftop solar potential in India by the Institute for Energy Economics and Financial Analysis (IEEFA) in 2019, rooftop solar was the fastest growing renewable energy sub-sector in India with a compound annual growth rate of 116 percent between 2012 and 2018. But despite this, it fell behind after the initial run.
Though rooftop solar is still at a very nascent stage in India, the sector has very huge potential, said a spokesperson of Tata Power, one of the largest power companies in India that install residential, commercial and industrial rooftops. “And multiple innovations can further enhance this.”
These include microinverters that enable more power generation even under conditions of shade (where traditional rooftop solar is not as effective) and new applications that enable fixing solar panels on the facades of buildings and balconies of apartments, he said.
Electricity, however, is a concurrent subject falling under the ambit of both the state and centre, he said. “But polity at the level of state governments, together with the impact of Covid-19, has not enabled the growth expected in the last two years, because rooftop solar is not seen as a necessity.”
The centre’s policies leave more to be desired too. Policy uncertainty on net vs gross metering has added a lot of confusion, explained Vibhuti Garg, an energy economist and one of the co-authors of the IEEFA report. Net metering permits domestic or commercial producers of solar energy to export their surplus energy back to the grid (and this is adjusted against their electricity bills), while in gross metering, they are paid a fixed tariff for the total power generated while paying power distribution companies (discoms) for the energy they use.
“A middle ground needs to be achieved as with gross metering, consumers have no incentive to deploy expensive solar rooftops. Uncertainty over duties also needs to be resolved,” she emphasised.
The lack of enough financial options has been a concern too since the initial costs of installing rooftop solar are still high. In fact, financial assistance is one of the factors that could help accelerate the pace of rooftop solar installations, the IEEFA report had argued.
But Pandit stresses rooftop solar is also far more economically viable than our large-scale utility projects. Large industries, godowns and public buildings have huge commercial rooftops; why aren’t we using them yet, he asked. “They are close to the end-user, they already have the electricity infrastructure in place, it will require some modification but nowhere near as putting it miles and miles away and running huge transmission towers to connect the 100, 200, 500 MW solar farms which just decimate the countryside. Policymakers should focus much more energy in making such end-user-driven, distributed energy interventions more viable than to take the easy route.”
Rooting for rooftop solar
All stakeholders agree that there are several changes that can be made to give rooftop solar a much-needed push. A policy shift is extremely crucial.
“When we started off, we saw many centralised projects amounting to 100 or 500 MW; but in any situation, decentralised RE – such as rooftop solar – is more sustainable,” said Rangan Banerjee, head of the Department of Energy Science and Engineering at IIT Bombay. “Land is always a problem, so it makes more sense to go for distributed photovoltaic rather than centralised, but the way structures of society, politics and business exist this is unlikely to happen unless this is pushed forward actively.”
Decentralisation is indeed key, agreed Debajit Palit. “With this, electricity can be used closer to the generation point to decrease transmission and distribution losses,” he said.
This is one of the main features where rooftop solar scores far higher than large-scale solar in the country. Moreover, storing power – deploying batteries – will play a key role in the success of solar rooftop in the future, as consumers won’t have to then rely on discoms for the supply of power, commented Garg.
“It would also result in an avoided cost for discoms to build infrastructure for the supply of electricity to such consumers for only some part of the day. But for this, India needs to implement Time of Day pricing so that investors and developers will be encouraged to deploy batteries in India along with solar rooftop,” she added.
However, focusing on rooftop solar doesn’t mean that large-scale utility projects should be shelved altogether. Large scale solar would be useful as long as projects are sited properly, such as in areas that are already degraded like abandoned mines, said Pandit.
“We’re not opposing solar energy by any means – not at all,” he added. “But we should do it properly. The best way to do that would be to first target the grey and dark infrastructure where we can site solar so that it won’t take away our precious ecological assets.”
Pandit argued for incentivising rooftop solar especially in the commercial sector and public buildings such as schools, and government offices. “These are great places for installations. Also, whenever a large plant is proposed, we need to conduct a cost-benefit analysis by comparing it with an alternative that is much more end-user based. We need to start from what the requirement is and then go from there.”
Banner image: A representational picture of a rooftop solar project in the U.K. In India, the rooftop solar sector has not been able to take off. Photo by Department of Energy and Climate Change (U.K.)/Flickr.