Siam JNK Co., Ltd.

Siam JNK, a manufacturer of industrial rubber components, faced rising electricity costs that were eroding margins on their export business. With a 15,000-square-metre factory in Rat Burana, the rooftop offered an ideal platform for solar generation.

Project scope

We designed and installed a 253 kW grid-tied system using 575W bifacial monocrystalline modules mounted on a ballasted flat-roof structure — eliminating the need for roof penetrations and preserving the factory's waterproofing warranty.

Technical highlights

The system employs three 80 kW three-phase string inverters configured in a master-slave arrangement for parallel grid synchronisation. A dedicated surge protection and isolation scheme ensures compliance with MEA interconnection requirements. The EMS platform provides minute-by-minute granularity across 24 string-level monitoring points.

Results

Annual generation exceeds 360,000 kWh, reducing grid consumption by 22% during production hours. The factory achieved a blended electricity rate reduction from 4.4 THB/kWh to an effective 3.2 THB/kWh after solar offset — a 27% cost improvement. Payback is projected at 4.8 years.