Energy savings from advancing the Indian Standard Time by half an hour

Since mechanical clocks were invented, three separate sequential adjustments have been made to timekeeping – the adoption of mean time, of time zones incorporating standard times, finally that of daylight saving time (DST).
India has accepted mean times and a standard time, but has resisted
adopting time zones or DST for several reasons.
Dilip R. Ahuja*, D. P. [...]