New Delhi: Assam’s decision to set its clocks an hour ahead of the rest of India could cause chaos in the railways, according to a leading scientist who proposes instead the entire nation moving half-an-hour ahead in order to save on daylight, energy and productivity.

Assam has decided to switch to Bagaan (tea garden) Time, set an hour ahead of Indian Standard Time (IST), chief minister Tarun Gogoi said on Wednesday. He said IST had affected the state’s productivity by forcing Assamese to follow a schedule that was not suited to them.

“All states will save electricity if we were to advance IST by half-an-hour. The amounts of savings will vary in different states from 0.2% to 0.7% of daily consumption. As a percentage of peaking energy consumption, however, the savings are very significant, about 17-18%," said Dilip Ahuja, scientist and author of a 2012 research paper commissioned by the Union ministry of power.

IST—set five-and-a-half hours ahead of the international Greenwich Mean Time (GMT) and introduced in 1947—has been chosen with reference to a central station sited 82º 30’ longitude east and 23º 11’ latitude North, passing through Allahabad district in Uttar Pradesh.

An example of the inconvenience faced by north-eastern states is that it starts to get bright before 4am IST in June in these states, and dark by 5pm IST in November.

Those who advocate a separate time zone argue that people in the North-East could begin their day an hour earlier—time that is currently wasted.

This is not the first time a separate time zone has been suggested in India, especially for the eastern states. The proposal has been debated and rejected but such moves have also thrown up alternative ideas.

In 2006, the Planning Commission recommended the introduction of two time zones in the country, saying it would save “a lot of energy".

In 2002, based on a suggestion by then governor of Tripura, the department of science and technology formed a high-level committee to explore the feasibility of two time zones, given the longitudinal difference between the furthest regions of the country.

The committee concluded against the idea of separate time zones. Separate time zones may not provide any major advantage to the states, it said, and such a move may actually pose difficulties due to the different timings that would have to be framed for airlines, railways and communications services.

It, however, recommended that individual state administrations could take such a step.

“Advancing the work/institutional timing in appropriate states would be more effective solution, which can be implemented through administrative actions by the concerned state," the committee recommendation said.

Since independence in 1947, the IST has been the official time for the whole country.

Pre-independence India had two time zones. In the East, Calcutta Time was 5:30:21 hours ahead of GMT, while Bombay Time in the West was 4:51:00 hours ahead of GMT.

Calcutta Time was abandoned in 1948 and Bombay Time in 1955.

The term Bagaan Time in Assam reflects labour laws, such as the Plantations Labour Act of 1951, which allow governments to set local times for particular areas.

Tea gardens in Assam already work to local clocks set an hour in advance of IST.

Meanwhile, scientists have come up with a solution that they say could solve the North-East’s time difference troubles without having to introduce a separate time zone.

In the research paper published in 2012, scientists from the National Institute of Advanced Studies (NIAS) in Bangalore recommended advancing IST by half-hour so that it is six hours ahead of GMT.

The paper projects savings to India of more than 2 billion kWh of electricity every year if this step were taken.

Ahuja, author of the 2012 research paper, says that different time zones can be potentially problematic in India. “Government offices in those states will close at different times and would be accessible only 75% of the time which can cause a potential loss of productivity," he said in response to emailed queries.

Ahuja also says that different time zones could cause chaos for Indian railways, although airlines may still manage. “India is a country where trains change tracks by manual switching. Different time zones could cause major confusion in communications between train operators and lead to accidents," he added.

Kapil Kaul, South Asia CEO of Capa, an aviation consulting firm, said, “Separate time zone would not have a major impact on airlines, except they will have to adapt to arrival and departure timings. In the US, there is a time difference between West coast and East coast, but it does not create big problems for airlines."

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