INTRODUCTION
Ever increasing energy demand, fast depletion of fossil fuels, along with environmental concerns has already made path for emergence of Solar Energy and Solar PV plants are being installed in large scale. However, large Solar PV installations are essentially land intensive which will always be a premium commodity. In the direction of conserving the precious land & water, installing Solar PV system on water bodies like lake, reservoir, canal etc is also an emerging option and becoming attractive particularly when big generating companies like NTPC etc. are having large reservoirs at many stations. Apart from land conservation, Floating PV installations have many other benefits like increase in performance of solar PV panels due to cooling effect, water conservation, reduction in algae growth, quicker installation etc. The main component of floating solar PV system is the floating platform or floaters on which solar modules are installed. Although this concept has become quite prominent worldwide for last few years with installation of large-scale commercial plants, the Indian scenario was not very promising, mainly because there was hardly any availability of floaters produced in India. The cost of imported floaters was also very high. The situation has changed to some extent in last two years with few commercial players entering into this segment.
TECHNOLOGY BRIEF
I. Design Implemented for 100 kWp pilot system in NTPC Kayamkulam (Weight 230kg/kWp)
In this design, the floating platform consists of main/solar floater, Access floater, connectors, rubber gasket, plastic insert as integral part of main floater and rubber gasket. Illustration of key components e.g. main floater, access floater & connector are as shown below
The solar panels are installed in a landscape orientation with one solar panel fixed on two sets of floaters on either side. The weight of material is approximately 230 tons/MWp. The main challenge faced in this design was production of complex design with blow mould machine available in India.
II. Design implemented for setting up 1 MWp project at NTPC Kawas (Weight 80kg/kWp)
Based on the experience of previous design it was found that to reduce the cost of floaters, few technical interventions as below could be taken up.
I. Change in orientation of solar panels: so that one solar panel could be supported by one main floater each on either side, instead of two as in the earlier design and thereby reduce the floater by almost half.
II. Change in design of floaters for weight reduction: The complexity of floater is reduced by making the main floater in two-piece, rectangular base and vertical inserts of two heights, as per tilt angle. Presently height of the insert is corresponding to tilt angle of 6 deg.