Karnataka to harness solar energy from 40 lakes with floating panels

Eco-friendly initiative promises to reduce electricity costs and enhance water resource management by generating 2,500 MW of renewable energy across 10,000 acres of waterbodies

In a promising convergence of science, environment and water resource management, Karnataka government is making strides towards generating solar energy from its waterbodies. Three government departments — minor irrigation, water resources and Karnataka Renewable Energy Development Ltd (KREDL) — are joining forces to create the first-ever ‘water surface solar energy parks’ in southern India.

While the project is in its initial stages, the initial enthusiasm has sparked exciting possibilities for harnessing renewable energy to achieve self-sufficiency in micro-communities.

The initial impetus for this project, now considered a viable option, is the collaboration between three organisations with expertise in water and renewable energy. This strengthens accountability and feasibility, said NS Boseraju, the Karnataka minister for science and technology and minor irrigation.

“The department has identified 40 lakes, each exceeding 100 acres and maintained under the Lift Irrigation Scheme. These lakes, covering approximately 10,000 acres, have the potential to generate around 2,500 megawatts (MW) of electricity. These lakes typically maintain water levels of 50 to 60 per cent throughout the year, making them suitable for installing floating solar power units,” Boseraju told this reporter.

“The primary objective of this initiative is to reduce the electricity costs incurred by the irrigation department for irrigation projects,” he added.

Nationally, only 1 gigawatt of electricity is currently generated through floating solar panels. There is significant potential for installing these panels both across the country and within Karnataka. A significant advantage of floating solar panels is that they do not require additional land, making them an optimal method for solar power generation.

Officials acknowledged that implementation costs may be slightly higher, but considering the long-term benefits, the cost could be recovered within the first five years of operation.

Outlining the role of the minor irrigation ministry, Boseraju said the perennial availability of water in many parts of the state will be leveraged to establish waterbody solar parks. The ministry is already creating platforms to conserve waterbodies and is driving a movement to encourage the formation of working groups to manage these resources for domestic water supply, irrigation, groundwater recharge and now, solar power production.

“An additional benefit could be the development of these waterbodies into water tourism destinations. A large-scale lift irrigation project is also underway to ensure sufficient water levels to harness all these benefits,” Boseraju said.

“We will soon convene a meeting with leading experts, including scientists, technologists, hydrologists, environmental scientists, bureaucrats and renewable energy specialists, to formulate feasible models for setting up waterbody solar parks,” he added.

A preliminary meeting was recently held with the secretary of the water resources department, the managing director of KREDL and secretaries from the minor irrigation. The meeting identified 40 lakes, each exceeding 100 acres and maintained under the Irrigation Scheme.

A final decision will be made following discussions with subject matter experts to thoroughly assess the feasibility of installing floating solar panels on the lakes.

Secretary for minor irrigation Raghavan told this reporter that Karnataka has 3,779 different types and extents of waterbodies, out of which 50 percent are perennial and hold water all the time.

“These waterbodies cover nearly 10,000 hectares and offer so much surface open to the skies. Even if we cover 50 per cent of the total waterbody surface with solar panels, we can expect to generate 2,000 MW of solar power for at least 10 months in a year, with slight variation in the remaining part of the year. This will also help us reduce the evaporation loss of the water by up to 50 per cent. So it is a win-win situation all the way,” Raghavan said.

Engineers in the minor irrigation department and KREDL hailed it as the best eco-friendly power generation system. However, they cautioned that the expensive panels require proper maintenance for optimal performance. A separate set-up for maintenance needs to be created, or it could be handled by local stakeholders to enhance the system’s efficacy.

The first phase of this project will be rolled out in five districts — Bengaluru Rural, Bengaluru Urban, Ramanagara, Kolar and Chikkaballapura — which are being considered for perennial filling through nearby lift irrigation projects, not just during the monsoon season.

Electricity supply companies agree that power generation is one aspect and the revenue generated by transporting it into the grid is another benefit of the entire process. The existing power grid infrastructure can synchronise the power received from the water’s surface. The solar panel programme can be wheeled into the grid for various purposes and any power that is unused and produced by this system will be paid to the government or any other organisation that will run it.

(Courtesy – Down to Earth)