FLOATING SOLAR PANELS
Renewable power for human need has gained momentum globally, particularly in the ackdrop of air pollution by fossil fuels resulting in climate change. India is blessed with plenty of sunshine, mighty rivers, thick forest cover, glacial valleys. Solar power has a huge potential in India. Its simplicity in manufacture, erection and operation affords a unique advantage.
Shekhar Dutt, Former Governor of Chhattisgarh
Biswajit Das, Former Member Hydro West Bengal
PRESENT TREND IN INDIA
In India, unlike USA and China, free availability and the cost of Land is one of the major constraints to development of Solar Power. Demand for land for homesteads, agriculture and irrigation are sharply increasing with population growth and urbanization. Therefore, solar panel installations on existing building rooftops are gaining popularity. Solar Power production connected to grid is 2,766 MW as on September 2014.
The canal top solar panels in Gujarat are advantageous because land cost is eliminated and evaporation loss from the canal is reduced. A project for utilizing 35,000 sq. KM in the Thar Desert for producing 700-2100 GW Solar Power is planned. New transmission lines are needed to evacuate power which will have to be run with 17-19% LF (for solar power) instead average 60% LF (overall power) resulting in substantial time-cost hike.
An investment of USD 100 billion has been earmarked in 2015 for developing 100 GW of Solar plant by 2022. Solar power can replace the base load of the power generated by fossil fuel, mainly coal. This will reduce the carbon dioxide emission and its negative effects.
FLOATING SOLAR PANELS
Similarly, reservoir surface of Dams for Hydropower, Irrigation, Water supply, Flood control, etc, could be utilised. There are more than 4857 large dams 15m high from deepest foundation; refer National Register of Large Dams, (Central Water Commission , GOI) in India and having 4,68,08,683 Sq. KM surface. Even if 30% of effective surface area is available, considering reservoir depletion during lean period, the net area will be 1,40,42,604 Sq.KM. Considering that 1 MW solar panel will require 20,000 Sq. m of surface area, including servicing area; the total available 1,40,42,604 Sq. Km surface area will have a potential of generating 7,02,130MW.
There are about 59 large Dams with 100m height or more and 1 km cube reservoir capacity which have more than 10,000 sq. km reservoir area. Even if 30% of effective surface area is available the net area will be 3,000sq km. 3,000 sq. km reservoir areas could generate 150,000 MW of power. The Solar panel could be installed over light weight interlinking pontoons. The reservoir will have an existing substation and transmission line to be used for power evacuation. The Solar panels will also substantially reduce the evaporation loss. As the Solar power will be scattered all over India the benefit will be well distributed amongst all regions without much investment in transmission and distribution system.
The efficiency of the panels for generating electricity is higher when they are on a water body, as this allows the panels to maintain the Ambient Temperature even during high sun radiation. The panels attract less amount of dust as they rest on water, meaning less washing and lower maintenance cost.
The best option is to develop a mixed system by which part of the Solar Power can be consumed locally and the surplus supplied to grid as a base load. Solar Panels with storage batteries are an excellent solution for smaller consumers in isolated areas. Hydro Power takes care of peak and fluctuating loads and can store tremendous amount of energy in its reservoir to meet hazards of instantaneous rise and fall of thousands of MW of power demand in the system. Solar Power can take care of peak load efficiently and at a low cost. Moreover, Solar Power can contribute to the base load of the grid, even with its intermittent supply of energy. Solar Power can thus replace part of the Fossil Fuel Generated Power to reduce the carbon emission substantially.
SOLAR PANELS ON WAGONS
Indian Railways (IR) is one of the largest public sector undertakings in India in terms of total transport volumes and facilities. The roofs of wagons give an excellent opportunity to fix Solar Panels.
Wagon volume in Indian Railways is approximately 250,000 nos. out of which 150,000 are on the move. The surface area of wagon roofs is about 60 sq. m and that of a coach roof is 75 Sq.m. Even considering 70% of rooftop areas have Solar Panels, each wagon/coach will have a potential of effective Solar Power of 2.5KW and totalling 375MW in 150,000 moving wagons.
The maintenance and safety of floating panels during inclement weather may be an issue. Fixed structures on piles similar to those at offshore facilities could be an answer. The enormous potential and multiple benefits from floating and wagon roof top panels demands a detailed study and a feasibility report.