During the hot months between March and November, men have been ordered to wear trousers and shirts instead, and these do not have to be tucked in any more.
Officials and ministers have also been told not to turn their air-conditioners below 24C.
In June, the government introduced daylight saving, and the clocks moved forward by one hour, in another attempt to cut energy consumption.
It has said it will also soon spend $6bn (£3.6bn) on new power plants, operated by private companies.
The current state-owned plants have not been able to keep up with Bangladesh’s large population and its economy, which has been growing at about 6% annually for the past five years.
The energy sector in the country has been beset by allegations of mismanagement and corruption.