GSAT-18 cost: PAC tells space dept to be economically prudent

The Department of Space, however, said that not utilising the transponders for the duration was as per plan.

The Committee wondered “how it would be economically viable to keep six Extended C-Band transponders idle for 11 years for the sake of utilizing for a period of 5 years and within five years as per New Space India Limited (NSIL) guidelines, its replacement has to be initiated before 3 years of its end of life. In view of the above, the Committee recommends the Department to be more cautious and economically prudent while planning projects involving substantial amount of public money”.

While deciding the optimum configuration for a satellite the department of space looks at several factors, including availability of spectrum, coverage requirement, spare capacity needed, and continuity of service. For GSAT-18, it considered several factors.

First, GSAT-14 was being carried on a development flight of the GSLV vehicle, whose performance at putting the satellite in correct orbit was still uncertain. Second, all the transponders on GSAT-14 were to be utilised, meaning only the ones in GSAT-18 would be available for redundancy. “Further, these transponders provide redundancy to mitigate any in-orbit failure of operational transponders,” the Department of Space said.

Third, the mission life of GSAT-14 is until September 2027. GSAT-18 will take over after that until 2032. Fourth, protecting the orbit spectrum was also one of the considerations, with non-occupancy of a spectrum for three years leading to a loss of priority in utilising it. Fifth, many of the systems and subsystems used in the satellite are the same for all transponders, meaning the additional cost of the six transponders was insignificant when compared to the financial implication of launching it separately.

The panel, however, said that non-utilisation of these transponders for five years had already led to a loss of revenue to the tune of Rs 117 crore. “In the case of not carrying 6 overlapping Ext C-Band transponders on GSAT-18, it would have required to launch additional satellite to ensure continuity of service and occupancy of orbit spectrum, which would be substantial. For instance, the realisation of GSAT-14 with 6 Ext C-band and 6 Ku band transponders cost Rs 110 crore in January, 2014 apart from the launch cost,” department of space said.

The committee also asked the department of space about the cost being incurred for maintenance during the idle period of 11 years.