In December last year, SECI announced an EOI for 10 GW of floating solar projects, which was later adopted into the government’s revised 227 GW RE target for March 2022. Several large floating solar projects have been announced subsequently over the last few months. But bid deadlines have been continually extended and progress has been slower than expected. Examples include:
- 1,000 MW project at Ujjani dam in Maharashtra – EOI was submitted by 24 companies in June 2018 but a committee has now been formed to assess technical feasibility;
- 150 MW project at Rihand dam in Uttar Pradesh – the tender document was issued by SECI in April 2018 but bid submission has been postponed multiple times;
- 100 MW project in Uttar Pradesh spread over multiple canal sites – tender issued by the state irrigation department in June 2018;
We believe that the government agencies have been mistaken in their assumption that because of no land requirement, higher power output due to cooling effect from water and easy availability of water for cleaning, floating solar would be faster and cheaper to build in comparison to ground-mounted solar. In practice, the big dam sites are very challenging because of deep and sometimes, unsuitable reservoir beds. In most cases, there is little information available on water flows or site topography. Extensive preparatory work by way of bathymetric and hydrographic studies is therefore required to establish techno-commercial feasibility. These studies may not only delay the project implementation timelines considerably but may also rule out feasibility of some sites altogether. SECI belatedly released an EOI for empanelment of consultants for these studies just two weeks ago.
Another short-term problem for floating solar is lack of domestic float manufacturing capacity. Being volume intensive, floats need to be manufactured close to project sites; transporting them over long distances is not viable. Ciel & Terre, the French floating solar specialist, has just announced completion of its 50 MW manufacturing plant in Maharashtra but many more such units will need to be set up all over India to meet the growing demand.
Special BOS requirements also means that capital cost of floating solar projects is higher in comparison to ground-mounted solar by about 10-20%. In other words, cost of power from floating solar is likely to be higher, not lower, offering a negative surprise to the procurement agencies. But the cost difference is expected to disappear over time.
Having looked at some international case studies and spoken to various market experts, we believe that floating solar is indeed a compelling and viable technology. But its best application in India lies in small-mid size man-made reservoirs near urban centres or at industrial sites rather than at huge dam sites.
