Power | Telecom |
Requirement of modern survey techniques for expeditious planning & implementation of tansmission line projects
The installed generating capacity in the Indian Power System is approx. 100,000 MW at present. In spite of having such capacity, there is 12 per cent deficit in peak demand and 6 per cent deficit in energy. In order to bridge these gaps in demand and supply, Government of India has evolved an ambitious power development programme. In this programme more attention is given to development and strengthening of transmission systems so as to supplement the shortcomings of the past. The programme envisages addition of about 100,000 MW generating capacity along with matching transmission network within the next decade. The transmission system, thus, to be planned and implemented in the next decade is of the order of 60,000 circuit kms in the EHV range and the investment in the sector is of the order of Rs. 80,000 crores. In order to execute such magnitude of transmission system, which is of much higher order than those totally implemented in the last 5 decades, precise planning, costing, scheduling etc. would be required. Optimum deployment of resources also would be of prime target in implementing these transmission systems. As transmission lines have to traverse the length and breadth of the country, for evacuation of power from generating stations to load centers and beneficiary states, the topographical & geographical nature of the terrains play significant influence in the project cost and implementation time. Hence, it is essential that at the planning stage itself various alternative routes and technical solutions for transmission lines be examined in detail. For undertaking such studies, one of the major requirements is obtaining adequate information regarding physical constrains, environmental factors etc. along the route so that optimum solutions are identified. Subsequently, during implementation of the project, it is required to obtain elaborate details about terrain, soil conditions, constraints etc. of the route for proper resource planning, costing etc. as well as reduction in implementation time. Presently, conventional methods of survey like walk over survey, preliminary survey and detailed survey are carried out at various stages from conceptualization of the project to implementation, which are time consuming tasks. As manual conventional methods are used for these surveys, which are conducted in not so friendly terrains, there is possibility that the results do not reflect adequately the true picture the terrain in great details. Presently, there are new means available to conduct route survey using remote sensing, aerial survey, GPS based survey etc.
These techniques are said to have edge over conventional techniques in terms of credibility of data but are expensive, require lot of expertise, specialized equipment and may have certain other limitations.
This paper details out the basic concepts of an Extra High Voltage (EHV) transmission line specifically relevant to surveying, type of surveys presently done at various stages of a transmission line project, their limitations etc. The Paper is being presented to a gathering of experts of GIS, GPS etc. The idea is to make them aware of specific requirements of a transmission utility like POWERGRID so that if fast and more accurate solutions are possible, the experts can address the same to streamline appropriate survey systems for power transmission applications.