The major Bhadla solar park in India’s desert state of Rajasthan has been leading the country’s transition towards renewable energy for its fast-growing economy and 1.4 billion people. However, the momentum in its roll-out has been hindered by difficulties encountered in laying transmission lines.

Located on a sunny, hot and barren 57 km² site between Jaisalmer and Bikaner, just under 40 km from the heavily defended border with Pakistan, millions of solar panels have been installed at Bhadla, designed to generate 2,245 MW power. The project was completed between 2018 and 2020, with solar cells sited within expansive stretches of thorny grass in this remote region at a cost of $1.3bn, funded by private investments arranged by power producing companies.

The first two of the park’s four phases were developed by state-owned Rajasthan Solarpark Development Company, which was joined by other energy companies for the latter phases. Phase one comprised 75 MW capacity, phase two 680 MW, and phases three and four are 1,500 MW combined.

All operators, says Vivek Sharma, Deputy Manager with Rajasthan Renewable Energy Corporation, have had to deal with desert sand settling on the solar panels, diminishing their power generation capacity. Arranging sufficient water for cleaning has been a problem, so some operators use roller brushes to wipe away the sand and dust.

Water is scarce in the desert but cleaning sandy dust off solar panels is vital
Photo: Raghavendra Verma

Bustards and power lines 
Another problem, which may hinder further development of the solar park, are restrictions placed on the overhead transmission lines to protect an endangered bird species – the Great Indian Bustard. After frequent instances of these birds flying into the powerlines, in April 2021 India’s Supreme Court banned new overhead lines in their habitat that overlaps the sites of new solar projects, which includes Bhadla as well as other major solar parks in Rajasthan.

‘It a critical issue and we are making efforts to find a balance between wildlife conservation and harvesting renewable energy in the region,’ notes Ravi Verma, Member of the Governing Council of Solar Power Developers Association. ‘Wherever possible the solar power companies are sharing the transmission towers or rerouting their lines.’

Some 33 kV lines are also being put underground by grid companies as a result, although not yet at Bhadla, where lower capacity lines were already in place. However, the undergrounding of transmission lines of 66 kV and higher voltage levels for export of bulk power is technically unfeasible, concluded an expert committee of various government agencies, including the Central Energy Authority (CEA) in August 2022. The highest voltage transmission line used in Rajasthan is 765 kV, transmitting power for long distances.

Underground high-tension cables through cooling systems involving a constant circulation of insulation fluid entail additional expense and long shutdown hours in case of any fault, said an engineer at Indian power company NTPC (the central government-owned National Thermal Power Corporation).

As an alternative, the overhead transmission towers in the endangered bird habitat area are being fitted with bird diverters that are made of reflecting materials. However, this will not enable Bhadla operators to fully comply with the bustard ruling.

Land use issues 
At present, transmission lines remain in short supply and, in November 2022, solar power producers were told by the grid management companies to reduce their production at Bhadla by 10% as a result. The Indian Express newspaper reported: ‘It is a major problem for solar developers, who typically bid at wafer thin margins, and a 10% curtailment could end up wiping out the margin for the developers.’

Transmission issues have been worsened by the fact that as more solar power projects have been built in the region, an extensive network of transmission lines have sprung up criss-crossing each other and creating rights of way challenges for operators, according to Sharma. For this reason ‘they often have to go around the existing solar projects or parks which are spread over several kilometres, so the project cost for the new developer could be much higher’.

Villages also pose serious right of way issues to the solar project developers, as a large part of the government lands allotted for such projects are used by them for grazing cattle or some other community purpose based on informal but established tenancy rights. ‘Officers grant them to the companies without knowing the ground realities,’ comments Mohua Mukherjee, Senior Research Fellow at Oxford Institute for Energy Studies.

This sometimes leads to disputes that even reach the courts, resulting in stay orders on the project development and losses to the power companies.

Power sales to ‘discoms’ 
Another challenge faced by the power project developers is the reluctance of state power distribution companies (called ‘discoms’) to sign long-term power purchase agreements (PPAs) for solar, particularly since they understand that costs have been falling and may continue to fall. ‘They look for solar only because of their renewable purchase obligation,’ says Mukherjee.

Private power generators themselves do not like to sell directly to state discoms because of their poor credit rating, instead preferring the NTPC, Mukherjee adds.

Another challenge for major solar projects, including Bhadla, is electricity pricing, which is set by competitive bidding between various private companies offering to build and operate a section of the park. Given the intense competition in the sector, tariffs have fallen as low as Indian Rupees INR2.44 ($0.03) per kWh of electricity, which is fixed for the next 25 years – from a May 2017 auction through competitive bidding in Phase 4 of Bhadla projects.

Sharma says even lower rates have been set in more recently commissioned projects in Rajasthan, outside Bhadla, falling to INR2/kWh ($0.02), even though, as well as paying for setting up solar panels, project developers finance the transmission lines up to the nearest electricity substation.

Substations in the Bhadla area are owned by the Power Grid Corporation of India and Jaipur Vidyut Vitran Nigam Limited (JVVNL), the power distribution company (discom) of Rajasthan, which uses all the power generated from the first two phases of Bhadla solar park. The power from the last two phases is divided equally between JVVNL and Uttar Pradesh Power Corporation, the discom from the neighbouring state of Uttar Pradesh.

Another challenge for major solar projects, including Bhadla, is electricity pricing, which is set by competitive bidding between various private companies offering to build and operate a section of the park.

Growing volumes of renewable power 
Despite these problems, Bhadla is indicative of major growth in India’s solar power sector. In the last five years, the country’s installed capacity of solar power has risen more than three times, from 21.7 GW in March 2018 to 67.8 GW in May 2023, according to the CEA.

The significance of the feat has been immense as, according to India’s draft National Electricity Policy, no new thermal power plants will be built in the future, even as the electricity demand continues to rise rapidly. In 2022, India’s overall electricity consumption grew by 8.9% over the previous year to 149.7 TWh and the installed capacity of fossil fuel-based power plants still constitutes 56.8% of this total, according to CEA data.

As a result, the CEA projects that, by the year 2030, 450 GW of power will be required from solar and other renewable sources, such as wind, small hydro and biomass power, while their generation capacity in May 2023 was only 127 GW.

A significant portion of this is in Rajasthan, where more than 17 GW of solar capacity has been commissioned, reports the CEA.

Rajasthan – a solar hub 
Rajasthan’s importance in generating solar power is undisputed as, according to the Indian Meteorological Department the state, along with the western part of Gujarat, receives the highest solar irradiation in the country.

Such an advantage also makes Rajasthan an attractive destination for companies with contracts to supply power to other states, as Bhadla does to Uttar Pradesh. ‘Other states look at Rajasthan to fulfil their renewable power purchase obligations (under the Electricity Act 2003 and the National Tariff Policy 2006),’ says Mukherjee.

Under the Indian federal system, electricity markets and regulations are state based, but have national commitments to source a set proportion of energy from renewable sources. Some of the big power plants and interstate transmission lines are owned and operated by central government-owned companies, but they all supply power to state discoms.

There are also private industries around the country, installing solar power projects in Rajasthan, enabling them to purchase electricity by just paying a small transmission charge. They feed the generated power into the grid and avoid paying for the costly commercial rates for the power taken from discoms, comments Sharma. The result of these power market purchasing systems is that Rajasthan exports much of its solar energy and is currently consuming just 5,000 MW, he says.

Power management installation at a project site at the Bhadla solar park
Photo: Raghavendra Verma

Local power for irrigation 
However, for small villages that dot this state – one of India’s poorer regions – solar power has not been regarded as an unblemished bounty.

Managing current from solar energy is especially difficult for lighting load in the villages, where the demand peaks in the evenings, notes Jaideep Malaviya, Managing Director of Malaviya Solar Energy Consultancy and board member of the International Solar Energy Society. ‘At times the demand is so high that it leads to voltage fluctuations and grid instability,’ he says.

Villagers living near Bhadla solar park particularly feel snubbed. ‘Despite being very close to the world’s largest solar park, we are not getting any benefit,’ Ram Kishan Bishnoi, a farmer in Phalodi, 50 km from Bhadla solar park, told New Energy World: ‘I have no idea as to where the power from Bhadla park is going.’

Like most farmers in his village, Bishnoi travels several kilometres to his farm at a moment’s notice, sometimes in the middle of the night, just to switch on the irrigation pump. ‘We get power only six hours a day and even then, it trips several times. It often causes the pump motor to die out, forcing me to undertake costly repairs while my crops go dry.’

Power to run irrigation pumps in India is free in many states but is supplied only for a few hours at any random time of the day or night depending upon the excess load in the grid, says Mukherjee. From Bhadla solar park, all the power is transmitted through high tension lines to faraway places, she adds.

Voltage fluctuations 
There have, nonetheless, been initiatives to bring solar power to the Indian villages, such as in Modhera, Gujarat, which is fully powered with solar energy.

In 2022, under a pilot project costing $9.7mn, a local grid was created for the village and 1,200 houses were provided with 1 kW rooftop solar panels, along with net metering equipment. Additionally, the grid is supported with a 6 MW ground-based solar power generation system and a 15 MW battery backup unit.

It has been a qualified success. The Modhera project achieved the desired result of uninterrupted power and zero bills for most of the households. However, along with that came a constant fluctuation in the voltage, causing continuous dimming of electrical bulbs and frequent busting of gadgets.

According to Mukherjee, many discom engineers have not been fully trained and equipped to deal with intermittent and fluctuating current from wind or solar energy. ‘This optimisation also requires ancillary voltage stabilisation equipment and computer algorithms, which most of the senior electrical engineers are not trained for, and it is hard for the discoms to attract younger IT talent given the market competition for such talent,’ she explains.

In the future, for providing stability to the power grids, some of the new projects are wind and solar hybrid that will generate some power round the clock, continues Mukherjee. ‘Wind resources pick up during the night when solar is not available, and likewise wind resources are higher during the monsoon seasons when solar irradiation is reduced.’

Cheap and clean solar energy is now critical for India’s growth, especially with the pressure to reduce carbon emissions. With favourable policies and attractive tax concessions, the central and various state governments are pushing solar energy on a high growth trajectory.