The Chittagong Port Authority signed an agreement on Monday to install an 8.42 megawatt-peak rooftop solar plant, as the port looks to lower its electricity bill and draw less power from the national grid.

The deal with Greener Garments Initiative Ltd was signed at the port's One-Stop Service Centre. Port Chairman Rear Admiral SM Moniruzzaman and GGI Chief Executive Officer Mohammad Nure Alam signed for their organisations, according to statements from the port authority.

Panels will go on unused rooftops of buildings and sheds across the port under the government's Green Port Initiative. GGI will finance, design, build, test, operate and maintain the plant under an operating expense model, so the port authority says it will not need to put up capital at the start.

The port will buy the solar electricity at a fixed tariff for 20 years from the start of commercial operations. GGI will also supply power for the port's daily needs, reducing its reliance on the grid.

Port Secretary Syed Refayet Hamim said the port expects to save about Tk 1 billion, or Tk 100 crore, on electricity over two decades.

The plant is expected to be linked to the national grid through net metering, allowing surplus electricity to flow to the grid. The authority said the project would cut carbon emissions and support the country's renewable energy goals, as well as the Sustainable Development Goals and the Paris Agreement.

Chittagong is Bangladesh's main seaport and a major consumer of electricity for container handling, refrigeration and lighting. The authority has billed the project as part of a wider effort to make port operations greener and cheaper to run.