With a total area of about 40 square km and a population of just over 55,000, Diu has become the first district in India to run entirely on solar energy during the day. Diu, which is among the 10 least populated districts of India, has the perfect mix of resources barren land and high solar exposure required for setting up solar panels.
Diu Island, which was earlier fully dependent on the Gujarat grid for its power needs, now has a 9 MW solar park that generates sufficient electricity to meet the daytime power demand. Built on 50 acres of land, the solar park was executed in two phases by Bharat Heavy Electricals Limited (BHEL) and private sector company Ujaas Energy Limited. Rooftop solar panels have been installed atop 79 government buildings across the island. Besides, the local administration provides subsidies to residential consumers to promote maximum utilisation of Diu’s solar power potential.
The shift to solar power to meet local energy needs has helped Diu reduce its power costs and carbon emissions significantly. In addition, tariffs for domestic consumers (consuming 51-100 units) reduced by 35 per cent in 2017-18.
With greater utilisation of renewable resources for sustainable rural electrification, Diu has set an example for other states as well.
Transition to solar energy
The plan to install solar power capacity in Diu was initiated in 2012. The district’s vast swathes of barren land, low population density, and good solar exposure makes it ideal for solar power development. There are only two months of cloudy weather during the year. Even during these two months, in 2017, the daytime demand was met through solar power. Further, being a part of the Daman & Diu union territory, Diu comes under the central government, which made it easier to plan, fund and execute the solar park project.
Earlier, Diu bought electricity from the power grid owned by the Gujarat government and was paying Rs 8 million per month to get power. Since the power had to be transported through 25-30 km of transmission lines, there were significant transmission and distribution (T&D) losses of around 12 per cent. This also affected the supply voltage, which stood at 59-60 kV.
Today, in Fudam village of Diu, the sun shines bright over thousands of solar panels laid out on a rocky hilltop overlooking the sea. The 9 MW solar park, spread over 30 acres, was built in two phases. The foundation stone for the first phase, with 3 MW of capacity, was laid in 2014. It was executed by BHEL at a cost of Rs 255 million, and became operational in February 2016.
Diu had released a tender for the second phase in 2015. Owing to improvements in solar power technologies and benefits arising from economies of scale, considerable efficiency gains were achieved during this phase. Even with double the capacity of Phase I, it required a smaller area and lower cost to execute Phase II. With 6 MW of capacity, the second phase cost Rs 369.8 million and was spread across 20 acres of land. The contract for this phase was awarded to Indore-based Ujaas Energy Limited and the foundation stone was laid in 2016. It was commissioned in February 2018. The five-year operations and maintenance contract for Phase II was for Rs 15 million, as against Rs 15.7 million for the much smaller first phase.
Apart from the solar park, rooftop solar projects have been set up to support Diu’s emerging energy needs. Of the 119 government buildings in Diu, 79 already have solar panels installed on them, aggregating 1.27 MW. The government is now encouraging Diu residents to install rooftop solar systems. To this end, it is offering a subsidy of Rs 10,000-Rs 50,000 for installing 1-5 kW rooftop solar systems.
As a result of these interventions, Diu now generates sufficient solar power to meet its daytime requirements. The average annual electricity consumption of Diu stands at 5-7 MW while the total solar energy generated is about 10.27 MW
9 MW from the solar park and 1.27 MW from rooftop projects. Hence, instead of meeting 100 per cent of its power needs from the Gujarat grid, the island now generates solar power to cater to 30 per cent of its daily electricity demand.
As Diu now generates its own power, T&D losses have come down to 7 per cent. Further, voltage has improved with households getting 66 kV power supply, as against 59-60 kV, and at lower tariffs. The monthly electricity bills of local residents have decreased by around 12 per cent. Earlier, the tariff was Rs 1.20 per kWh for 0-50 units of consumption and Rs 1.50 per kWh for 50-100 units. However, once the solar power plants were commissioned, the Joint Electricity Regulatory Commission for Goa and the Union Territories removed the 0-50 units slab and revised the 1-100 units charge to Rs 1.01 per unit. For domestic consumers (consuming 51-100 units), the tariffs came down from Rs 1.80 per unit in 2016-17 to Rs 1.17 in 2017-18.
Diu used to spend Rs 8 million per month to import power from Gujarat. The solar parks and rooftop solar projects have helped the island reduce its import bill and save an estimated 12,960 tonnes of carbon emissions every year.
Given the impact of the solar panel installations, Diu is planning to set up a 6.8 MW wind power project by 2019 to achieve energy self-sufficiency. The plan is to develop four windmills at a cost of Rs 516 million. “Early this year, we were picked as part of India’s Smart Cities Mission. Renewable energy is one of the many steps we are taking to get there. Solar energy takes care of our day needs. For the night, we still have to import from Gujarat. With windmill projects, we will be self-sufficient in our energy needs. All of it will be green, renewable energy,” Hemant Kumar, district collector, Diu told a national daily.
Can Diu’s model be emulated by a bigger city? It would certainly not be easy; in fact, the administration is finding it difficult to replicate it even for Daman. Despite being twin territories, similar policies cannot be implemented because Daman is a heavily industrialised area with very little free space. According to a government official, a village can be electrified with just 5-6 acres of land and at a cost of about Rs 30 million. This sum is nothing compared to the cost of setting up a thermal power plant supported by T&D infrastructure. However, since solar projects require a lot of space, it is more viable to use barren land in rural areas for solar power development.
That said, smaller territories can learn from Diu’s success and replicate its clean and sustainable energy model.