An RMG factory's demand tracks a daytime shift, which is the closest match to solar output of any industry in Bangladesh. What that means for sizing, what a CGI roof on steel trusses will carry, and what buyers and certifiers actually credit.
Of all the industries in Bangladesh that put solar on a roof, ready-made garments has the easiest load profile to work with. A sewing floor draws its demand across a daytime shift: the lines, the lighting, the compressed air and the air handling all come up in the morning and come down in the evening. That is the same curve a rooftop array produces, and it means a very high proportion of what the roof generates is consumed in the building rather than exported at a lower value. The sector employs over 4 million people and generates more than USD 45 billion in annual export earnings, and with international buyers increasingly asking for green manufacturing credentials, the case for a rooftop plant now has two independent legs.
A typical mid-size RMG factory with 500 to 1,000 workers consumes 200,000 to 500,000 kWh per month. A 500 to 1,000 kWp rooftop plant will offset 30 to 50% of that consumption during daylight hours, which lands directly on the monthly bill. The reason the figure is a range and not a number is that it depends on how much of your consumption sits inside the solar day. A factory running one day shift will sit at the top of that band; one running a second shift into the night will sit at the bottom, because the night units have to come from the grid or from an export credit carried forward at a lower rate.
Beyond the bill, solar installations contribute to LEED, EDGE and BGMEA Green Factory certification, which is increasingly required by H&M, Zara, Primark and other major international buyers.
| Factory size | Monthly consumption | Recommended plant | Monthly saving | Annual saving |
|---|---|---|---|---|
| Small (200 workers) | 80,000 kWh | 200 kWp | BDT 2,52,000 | BDT 30,24,000 |
| Medium (500 workers) | 200,000 kWh | 500 kWp | BDT 6,30,000 | BDT 75,60,000 |
| Large (1,000 workers) | 450,000 kWh | 1,000 kWp | BDT 12,60,000 | BDT 1,51,20,000 |
| Mega (2,000+ workers) | 900,000 kWh | 2,000 kWp | BDT 25,20,000 | BDT 3,02,40,000 |
Before any of those capacities is real, two documents decide the ceiling. Under the Net Metering Guidelines 2025 the plant may not exceed 100% of your sanctioned load, or 80% of transformer capacity for medium-voltage consumers at 11 kV and above. Factories that have grown their production without revising the sanctioned load frequently find the ceiling binds well below what the roof would take, and that is a conversation with the utility, not with the EPC contractor.
Certification is where the commissioning paperwork stops being an administrative afterthought. An auditor will ask for metered generation data, not an invoice for a solar plant. Specify a monitoring platform that logs and exports generation at the level of detail your certification body wants, and make sure the handover pack includes the commissioning test records, the module and inverter datasheets with their IEC certification numbers, and the signed structural certificate. Assembling that a year later, from a contractor who has moved on, is painful.
Most RMG factories in Bangladesh use corrugated metal sheet roofs on steel trusses. These are generally suitable for solar mounting with clamp-based racking systems that do not require roof penetration. Vvon's structural engineers assess the truss spacing, purlin capacity and wind load before the mounting design is finalised. Factories built as pre-engineered steel buildings are particularly well suited to large-scale solar, because the frame was designed as a system and the drawings usually still exist.
Older buildings are the harder case. A factory that has been extended twice will have roof planes of different ages, different purlin spacings and different degrees of corrosion at the fixings, and each needs its own assessment. Where a roof is at the end of its life, the honest answer is to re-sheet before mounting rather than to fit a 25-year asset onto sheeting with five years left in it. A contractor willing to say that before contract is worth more than one who says it afterwards.
Which utility handles the application depends on where the factory sits: DPDC or DESCO inside Dhaka city, BPDB in the other major industrial centres, BREB through the local Palli Bidyut Samity in rural areas, and NESCO in Rajshahi and Rangpur divisions. The sequence is the same across all of them.