CT Logo

The canal bank and canal top solar project program was launched in the financial year 2014-15. Under this program, solar projects have been commissioned in eight different states (50 MW – canal banks and 50 MW – canal tops), including Gujarat, Karnataka, Kerala, Andhra Pradesh, Punjab, Uttarakhand, Uttar Pradesh, and West Bengal. Project capacities range from a minimum of 1 MW to a maximum of 10 MW.

However, the canal-top idea was first tabled at the 2011 Vibrant Gujarat Summit, post which the first canal-top project was commissioned in the state in 2012. The aim was to utilize the area above the canals, saving the government cost, time, and inconvenience associated with land acquisition.

The state of Gujarat has made great strides in harnessing the tremendous potential of solar energy through the pathbreaking concept of installing solar photovoltaic panels on canal-top to generate environment-friendly power. In November 2014, Gujarat government-owned Sardar Sarovar Narmada Nigam (SSNNL) had commissioned a 10 MW canal-top solar photovoltaic grid-connected power plant on Vadodara Branch Canal. The project was dedicated to the nation by the then United Nations secretary-general Ban Ki-moon on January 11, 2015. Later, another 25 MW canal-top solar power generation capacity was installed by SSNNL near Vadodara in 2017. The power being generated through canal-top solar panels are being used to run pumping stations of SSNNL. SSNNL will also set up a 100 MW canal-top solar power generation project atop the branch canals of river Narmada at an estimated cost of Rs 100 crore.

Over the past few years, SECI and various state agencies have come up with canal-based project proposals. The potential is immense and so is the opportunity for developers. Gujarat alone has a canal network of 80,000 km. According to Gujarat State Electricity Corporation Limited, using even 30 percent of this network could help set up 18,000 MW of canal-top solar capacity in the state – almost equal to the current installed coal-based capacity of Delhi, Rajasthan, and Telangana – while saving 90,000 acres of land, which is twice the size of Kolkata. In other words, installing solar panels over 30 percent of Gujarat's canals could help meet nearly a fifth of the country's solar power targets by 2022.

Another state, Punjab, has more than 1,500 MW of potential for the installation of solar power projects on its main canals. However, to date, only 20 MW of pilot-cum-demonstration projects have been commissioned by the Punjab Energy Development Agency (PEDA). Of these, two projects of 7.5 MW each had been commissioned on the Ghaggar branch canal and the Ghaggar link canal in March 2018, and two projects of 2.5 MW each were commissioned on the Sidhwan branch canal and the Ghaggar branch canal in March 2017.

After making the first airport to be fully powered by solar energy in India, Cochin International Airport Limited (CIAL) has been expanding the airport's solar power capacity. The expansion includes a 6 MW canal-top solar project on the Chengaltodu canal that runs through the airport. In November 2017, 4.5 MW of the canal-top project was commissioned.

The Haryana Power Generation Corporation Limited (HPGCL) has invited an expression of interest (EoI) to set up 16 MW of canal top solar photovoltaic (PV) projects at WYC Hydel Power Station at Bhudkalan, in Yamuna Nagar.

It has been more than seven years since the first project was commissioned. Not only has its performance been encouraging, but the project design and technology have also evolved to become more efficient. In 2012, when the Chandrasan project was commissioned, the land required for a 1 MW solar installation was about 5 acres. By 2015, with advances in technology, this came down to 4 acres. While the capital costs of canal-top installations are higher than their ground-mounted counterparts, the difference has been coming down. The 1 MW solar plant at Chandrasan, set up in 2012, cost Rs 177.3 million, 77.3 percent higher than the benchmark cost issued by the Central Electricity Regulatory Commission (CERC). The 10 MW canal-top solar plant at Vadodara, set up in 2015, cost about 47.6 percent higher than the benchmark cost. Going forward, once the technology and manufacturing processes are in place, the auctioning of such projects will create competition in the market and may reduce tariffs to a level comparable to ground-mounted projects.

The power output of ground-mounted solar panels decreases at a rate of 1 percent every year for the first 10 years. However, according to research conducted by the Gujarat Energy Research and Management Institute, panels mounted on Chandrasan's canal showed no degradation, and the power generated stayed stable for the three-year period they had conducted the study for. Not only do they perform more efficiently but, assuming that the generated electricity is utilized in the nearby areas, the average transmission losses of 4 percent and distribution losses of 3 percent are avoided. Apart from this, since the panels are placed on top of the water, they are cooled from below, which also increases their efficiency and enhances output by 2.5-5 percent. Essentially, this means the panels will last longer than 25 years, which is the average lifespan of a ground-mounted solar panel while producing more power due to increased efficiency. All these benefits have encouraged more players to take up canal-based projects.

Canal-top projects have the unique advantage of not using any land. In a country like India, the land is scarce and heavily contested. So, these projects provide an alternative and also save water. 

With the increasing population also comes the need to address the problem of water security. For a country relying primarily on monsoon to deliver the annual water supply, it becomes an issue of pivotal importance. The solar panels mounted on the canal-top block the radiation of the sun, thus helping to keep the water in shade. This reduces the evaporation of the water in the canal. According to conservative estimates, a 1 MW plant can save 9 million liters of water per year. As the area covered by the solar panels increases, a large quantity of water

is saved.

The water in the canals gives rise to algae growth due to abundant sunlight and moisture. Algae block and clog the irrigation and water pumps and spoil the quality of water. Thus, due to the fitment of solar PV panels and the absence of sunlight, algae growth is drastically minimized. This helps in lowering the cost of maintenance and extends the life of irrigation equipment. Furthermore, the solar panels can provide electricity to the irrigation pumps. Since the pumps are often located at remote locations, this would also solve the issue of transmission of electricity as well as strengthen the grid. This way, the canal top becomes the best administrative model for a community-scale solar-powered water pumping/ village electrification program.

Another advantage of the canal-top solar power plant is that the energy generation is closer to the point of consumption. This results in the minimization of the transmission and distribution losses of electricity, thus enabling urban and rural settlements to generate their own power. The generation at remote consumption centers would also enable the strengthening of the grid which in turn would improve the reliability of the power being supplied.

The canal-top power plant presents an amazing potential for replication. The project is easy to begin as very few approvals/clearances are required. Further, it offers a faster implementation period as no land acquisition/development is required. Since irrigation canals exist throughout India, it provides a fairly simple and economically viable model for replication