Grid linked PV Power plants are new to this country. Most of the power plants are one to two years old. Post construction, these power plants are functioning as per requirements of their PPA. Plant O & M is being done as per EPC Contractors & component manufacturers on long term contract basis, usually the plants solar field and module life of 25 years. It has been observed that the biggest O & M challenge is house keeping of the plant, i.e. minimizing soiling of plants.
At present, the plants generate revenue only from the sale of power. This blog aims at presenting the feasible solutions complementing O & M activity, deploying additional unskilled manpower like
(1) using the waste from water softening plant in dust abatement landscape consisting of water raceways to grow suitable species of micro algae and or species like Simmondsia chinensis (JOJOBA) as hedges along project perimeter.
(2) Use of softened water from module washing containing diluted phosphate free detergents to cultivate medicinal crops, herbs and vegetable below the arrays.
The above activity will
(a) Reduce the carbon foot-print and adds to the green quotient of the project
(b) Reduce the O & M cost (Module cleaning & cost of water is 44 % of total O & M cost in the first year of operation).
(c) Generate additional revenue from sale of JOJOBA seeds, dried algae & vegetables and generate additional unskilled employment in the neighborhood.
The layout plan of most of the PV Power plants executed till date in India have arrays of conventional ground based module mounting structures for all types of terrains and soil conditions. Customization of solar field is done to only accommodate the needed solar field area within the given non regular shape of land. Solar arrays have same structural form, except spacing and tilt throughout the country. Its like prescribing and building a flat roof house with glass doors and windows for all climate zones in the country.
I have also observed that Land development means just cutting, filling without consideration for maintaining the natural grade and drainage pattern through contour bunding and landscape innovation using local vegetation.
Therefore you find similar array layout (except spacing) and module mounting structure form ( not the structural member spec) looks the same in existing PV power plants, either in flat land or rolling terrains of Punjab, Rajasthan, Gujrat, Uttaranchal, Orissa, Bengal, Karnataka and AP.
A well designed plant layout with terrain specific grading, dust abatement system and land scape reduces the O & M Cost, generate additional revenue & employment.
I have observed that a functional landscape in real estate and infrastructure projects has positive effects on site micro climate, especially the resultant site temperature & dust reduction and wind patterns. Therefore I believe after few years of operation, a well designed PV power plant with functional dust abatement system reduces the power loss due to soiling. Losses due to high temperature (power loss due to module temp coefficient) might reduce as the plants get higher radiation, but due to changed site micro climate, the at site temperature is less than similar sites not landscaped.