Andhra Pradesh’s Simhadri Reservoir is now home to the largest floating solar power plant in India. The project is commissioned by National Thermal Power Corporation Limited (NTPC), India’s largest power generator. The project is being executed by Bharat Heavy Electricals Limited (BHEL) and is expected to commence operations on 21st August 2021 at 10:00 AM. The floating solar power plant in Simhadri Reservoir has opened the door for a potential new market.

How are floating solar power plants different?

Floating solar power plants, often called floatovoltaics, are a type of solar power plant installed on a water body. Floating solar power plants were first patented and built-in 2007 in Japan. The mounting is done on a structure that floats on the water’s surface. They can be installed on an artificial or natural lake, reservoir, basin or river.

In recent years, floating solar power plants have been researched as an alternative for ground-mounted solar power plants due to this advantage. The global market capitalization of floating solar power plants which was just $685.2 million in 2019 is expected to reach $2,301.8 million by 2026.

Several countries have invested in creating floating solar power plants to meet their growing energy needs without compromising on infrastructure. India is expected to have the largest market for floating solar power plants in the world, valuing over $608.9 million by 2026. India’s commitment to renewable energy means the NTPC is implementing this new technology to fulfill the goals set by the government.

What are the advantages of a floating solar power plant?

1.  Land occupancy

The primary requirement for a ground-mounted solar panel is land. Without sufficient space, the installation of a high-capacity solar power plant is impossible. The same problem is not faced when installing a floating solar power plant. The PV modules are mounted entirely on a floating platform. A small area is required for an electrical cabinet that connects the floating platform with the grid connection.

This setup ensures floating solar power plants can be installed in both rural and urban areas where land is limited and occupied. Renewable energy can be generated without locking in a large amount of land.

2.  Commissioning and decommissioning

Installation of ground-mounted solar power plants can have a long-lasting impact on the ground. The installation usually requires concrete foundations to provide stability. Decommissioning ground-mounted solar panels require further investment since the concrete foundations need to be removed from the ground.

On the other hand, installations and decommissioning of a floating PV plant are relatively easy. The plants are compact and require no installation of foundation. Therefore, decommissioning is as simple as removing the floating structure. The installation remains reversible throughout the use.

3.  Water saving

Water bodies in Mumbai have lost 20-25% water level due to evaporation. This increases significantly in regions with warmer weather. However, the installation of floating PV modules shelters the water body from the sun. This reduces the evaporation rates, which is useful for the surrounding environment.

Floating PV plants also reduce the amount of light that enters the water and reaches the ground. This limitation can dissuade the growth of algae – a popular problem in water bodies near factories and industrial areas.

4.  Maintenance

The last and most significant advantage of floating solar power plants is that it does not require an elaborate cooling system. The water surrounding the plant can be used as part of the cooling mechanism. Partially submerged or completely submerged PV modules are being tested for this application. Thereby reducing the average maintenance cost of the solar panels. 

These four primary advantages make the installation of floating solar power plants easy. However, installation poses three primary challenges that need to be overcome.

Which challenges need to be overcome?

1.  Engineering costs

Unlike ground-mounted solar panels which have a tried and tested installation methodology, the installation for floating PV plants is not easy. Engineering and manufacturing costs for the latter are higher due to the mounting structure required.

The mounting structure should have special qualities including corrosion-resistant, chemical-resistant, insulating and water-resistant. The material should always float on top of the water surface and at the same time, handle the weight of the solar panel. These requirements increase the installation and manufacturing cost of a floating solar power plant.

2.  Safety and protection

Floating solar power plants revolve around water and electricity. Special considerations need to be made for electrical wiring and connection for the safety of those installing and maintaining the plant. Furthermore, special considerations need to be made on how the installation will affect the safety of aquatic life. A wrong installation or loose wiring can cause irreversible damage to the topography of the waterbed.

3.  Degradation and decommissioning

Floating solar power plants will always be in contact with water and air, increasing the chances of corrosion and degradation. This can cause chemical leaching, rusting or catastrophic failures. The constant exposure to moisture can cause electrical failures. These can happen any time after the installation of the plant.

These three challenges show that special considerations need to be made during the set-up of a floating solar power plant. Each water body has a unique topography, aquatic life and chemical composition, therefore a generic answer cannot be implemented.

Where does India stand today?

By 2032, NTPC plans to have an energy capacity of 60 GW through renewable sources. This is approximately 45% of NTPC’s overall power generation capacity. The capacity will be achieved primarily through solar, wind and hydrothermal power plants. While NTPC has commissioned various other projects, there are three other floating solar power plants commissioned in India:

Ramagundam, Telangana100 MW
Kayamkulam, Kerala92 MW
Auralya, Uttar Pradesh20 MW

This goes to show the NTPC’s recognition of the new technology. As India moves towards a new renewable energy goal, a floating solar power plant is a potential market that deserves exploration.