From electronics to garments and glass, how industries turning factory roofs into power plants

When grid power goes out, production at factories does not necessarily have to stop anymore – at least not at facilities that have already invested in rooftop solar systems.

Across Bangladesh, manufacturers are increasingly turning their factory roofs into power plants as persistent load-shedding and gas shortages threaten to disrupt production, raise operating costs and make generators an increasingly expensive fallback.

For some factories, rooftop solar is no longer simply a way to cut electricity bills or meet buyers' carbon requirements. It is helping keep production lines running when the national grid cannot.

Infographic: TBS

More than 600MW of rooftop solar capacity has already been installed at industrial facilities, according to industry sources. A substantial portion is in export-oriented garment factories, while large manufacturers in electronics, steel, glass, ceramics, textiles and other sectors are also rapidly expanding their solar capacity.

The biggest installations have come over the past two years as the energy crisis deepened.

At Walton's manufacturing facilities, rooftop solar now generates 32MW of electricity, meeting around 30% of the company's total power demand.

"Another 25MW will be installed soon. By the end of the year, we can fulfil 60% of our total demand," said Engineer Md Nazmul Islam, executive director and head of electrical and renewable energy at Walton Group.

Producing about 28,500 megawatt-hours annually, the system generates power at Tk4.20 per unit – around one-fourth the cost of traditional generators, Nazmul said.

This estimated unit price reflects initial setup costs, regular maintenance, and the system's expected operational lifespan.

The investment's value peaks during load-shedding. Daytime solar power reduces grid reliance and avoids the costly operation of diesel or gas generators during outages.

However, for factories with a battery energy storage system (BESS), protection against power cuts extends beyond daylight hours.

Solar keeps production floors alive

Janata Jute Mills, an AkijBashir Group factory in Ghorashal, Narsingdi, has installed 25MW of rooftop solar capacity against a factory demand of around 21MW.

The plant also has a battery storage system, allowing the factory to use solar-generated electricity after sunset and reducing its reliance on the national grid.

Production from the solar plant began in 2023. It generates around 2.76 gigawatt-hours of electricity annually using panels manufactured by China-based Trina Solar and Huawei inverters.

"The solar system has helped us get rid of the hassle of load-shedding while allowing us to generate the power we need at a much lower cost," said Hussain Mohammad Al Amin, project manager at AkijBashir Group.

The group installed another 13MW rooftop solar system at its Akij Glass factory in Habiganj, including an 8MW battery storage system. "In factories equipped with battery systems, production can continue almost fully even during load-shedding," Al Amin said.

Across its particle board, ceramics, glass and other factories, AkijBashir now has around 90MW of solar generation capacity. It is working to add another 50MW and plans to install a further 75MW over the next two years.

The group's factories together require around 1,250MW of electricity, with solar currently supplying roughly 35% of that demand.

That ability to keep machines running is becoming increasingly valuable as industries struggle with both electricity and gas shortages.

PRAN-RFL Group, which operates dozens of factories across 18 industrial parks and employs around 150,000 people, has installed solar systems at 20 factories with a combined capacity of around 35MW. Its overall electricity demand is about 180MW.

"Load-shedding and gas shortages forced us to temporarily shut some factories at times over the past few weeks. But we have received tremendous relief at factories where solar power has been installed," said Kamruzzaman Kamal, director of marketing at PRAN-RFL Group.

The group currently meets 15-16% of its electricity demand from solar and expects that share to reach 50% by the end of this year. "Our target is to meet 100% of our demand from solar by 2027," Kamal said.

From emergency backup to business decision

For some manufacturers, the move to solar began as a response to the energy crisis. Now, it has become more of a business decision.

Rising Group Managing Director Mahmud Hasan Khan said, "We were almost forced to install solar at the factory in 2019 to deal with the gas crisis. Later, we installed solar at other factories from a purely business perspective because the cost of solar power is almost half that of grid electricity."

The group now has 14MW of rooftop solar capacity across six factories. Solar supplies as much as 60% of electricity demand at two garment factories and around 15% at two spinning mills.

The economics are increasingly difficult for factory owners to ignore.

Industrial electricity prices range from around Tk12.73 to Tk12.85 per unit, depending on the connection type, while the effective cost can rise to nearly Tk16 during peak nighttime demand.

By comparison, rooftop solar generally costs Tk4-Tk8 per unit, depending on the project, financing and technology.

The cost of installing the systems has also fallen sharply.

"Five years ago, it cost around Tk5 crore to install a one-megawatt rooftop solar system. Now the cost has come down to around Tk3 crore," said Super Star Renewable Energy CEO Mizanur Rahman.

His company has implemented rooftop solar projects at around 90 industrial facilities, with a combined capacity of nearly 100MW, and is working on more than 10 additional projects that will add another 20MW.

Omera Solar, a subsidiary of East Coast Group, has installed 130-140MW of rooftop solar at roughly 100 industrial facilities since 2021. It is implementing another 20MW at 12 facilities.

Omera Solar CEO Masudur Rahim said the pace of installation has accelerated over the past two years as the energy crisis has worsened. "A solar plant has a lifespan of around 20-25 years. Once the investment is made, there is little expenditure apart from maintenance," he said.

Factories race to add more capacity

The shift to solar is spreading across major industrial groups.

Abul Khair Steel, Ha-Meem Group, BSRM, Youngone Group, Meghna Group of Industries, Pacific Jeans, Team Group, DBL Group, Rising Group, Urmi Group, Microfiber Group, Palmal Group, Apex Footwear, Karnaphuli Shoes and Masco Group are among companies that have installed or are expanding rooftop solar capacity.

DBL Group has installed 5.5MW across seven garment and textile factories and plans to add another 16MW at 10 garment and ceramics facilities.

"Energy security at our different facilities and pressure from foreign buyers to reduce carbon emissions are driving us to invest rapidly in solar power," said DBL Group Managing Director MA Jabbar.

Meghna Group of Industries has installed 64.84MW of rooftop solar, meeting nearly 5% of its overall electricity demand. It plans to add another 50MW.

"Renewable energy generation and use have long been among our priorities. We are exploring creative ways to generate solar power not only on factory rooftops but also on building facades, boundary walls and road dividers," said Tanvir Mostafa, director of MGI.

For manufacturers, however, the immediate attraction is not necessarily the environmental benefit. It is the ability to keep a factory running when the grid does not.

Rooftop solar cannot meet the full electricity needs of most industrial facilities. But even a few hours of self-generated power can prevent production disruptions, reduce reliance on generators and cushion factories against an increasingly unreliable energy supply.

Government sweetens the equation

The government has also introduced a new incentive to accelerate rooftop solar adoption.

Under the Net Metering Guideline 2025, the government will provide Tk10.50 per unit for surplus electricity supplied to the national grid, according to a gazette issued on 1 September.

The Power Division estimated the maximum generation cost of rooftop solar systems equipped with batteries at Tk8 per unit. A 20% profit margin and an 11.25% premium will be added to the generation cost, taking the applicable price for surplus electricity to Tk10.50.

The incentive could encourage industrial consumers to install larger systems capable of producing electricity beyond their own requirements.

But for factories battling daily power shortages, the strongest incentive is already visible on the production floor: solar can keep the machines running when the grid goes dark.