Solar Inside a Live LPG Terminal: 40 kWp for GAIL at Madanpur Khadar, New Delhi

Why this site needed care

• An operating LPG facility: the roof sits inside a live LPG receiving terminal and bottling plant. Gas is handled on site every day, so every activity needed a permit and the plant's safety rules came before the construction programme.
• A working office roof: the array sits on the terminal's single-storey office block, and the roof had to stay accessible after the plant was built, so the modules could not simply sit low on the slab.
• Wind loads: an open, elevated array on a rooftop catches wind. The structure had to be designed and checked for it, not taken from a catalogue.
• A fixed three-month window: the PO gave three months from the letter of award for design, supply, installation and commissioning.

Working safely around gas

The nature of the site shaped how the work was done. All the permits required by the plant were obtained before work began and renewed as each stage progressed, covering vehicle and material entry, the installation work and electrical connection.

Because LPG is handled on site, special care was taken at every step: work was carried out only as permitted, under the plant's safety supervision, and in line with its rules for a gas facility. The plant was completed without disturbing the terminal's operations.

Design first

Before any steel was cut, MGetEnergy ran a shadow analysis of the roof to place the arrays where they would not shade each other or be shaded by nearby structures, and prepared a general arrangement layout for GAIL's approval.

The mounting structure was designed and analysed in STAAD, with a wind load calculation, and drawn in two table sizes (2 by 4 and 3 by 4 modules) to fit the roof. It is an elevated frame in hot-dip galvanised steel, minimum 90 micron coating, with C-section columns standing on M20 concrete blocks fixed with M25 bolts. The raised frame leaves a clear, walkable space under the modules.

Electrical design

The 124 modules of 325 Wp are wired in seven strings into a Growatt 40 kW string inverter with two MPPT inputs. A DC distribution box with 15 A string fuses and Type II surge protection feeds the inverter, and an AC distribution box with a 100 A four-pole MCCB and surge protection connects it to the terminal's LT panel.

Class 0.5 CTs and Secure meters record the plant's energy. The plant is protected by three earthing pits and five lightning arresters, with Polycab DC and KEI armoured AC copper cables throughout.

Handover

GAIL received a complete as-built dossier: shadow analysis, general arrangement layout, single line diagram, structure drawings, DC and AC distribution box layouts, module and inverter warranty certificates, meter test certificates, and a plant operation and maintenance manual written for the site. MGetEnergy then stood behind the work through a one-year defect liability period.

Result

• 40.3 kWp commissioned on 13 December 2018 inside a live LPG facility
• Inaugurated by GAIL on 30 January 2019
• GAIL certified the work as successfully completed as per the PO, with no extension of time

What this means for other PSU and industrial sites

Oil and gas terminals, bottling plants and other permit-controlled sites need a contractor who designs before building, documents everything, and works inside the host plant's safety system. The GAIL project is an early example of how MGetEnergy works on PSU sites, and the same approach has since carried into larger institutional projects.

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