Rooftop solar for factories in Sachin GIDC, Surat

How big Sachin really is

GIDC's estate table for October 2026 lists 2,596 plots of all types in Sachin, covering about 605 hectares of plot area, with 2,105 allotted, and marks the estate Saturated. That is the largest count in GIDC's Surat region.

An older MSME-DI profile of Surat district (GIDC figures from around 2010-11) recorded 2,075 units in production on 1,557 plots at the time. More units than plots usually means plots split into galas or shared sheds, so one roof can sit over several small businesses. Sachin is not a handful of large plants but thousands of small and mid-sized units packed close together, which shapes almost every solar decision below.

The SEZ and the Apparel Park

Two notified special economic zones sit within the Sachin area. The Ministry of Commerce's list of notified SEZs shows the Surat Special Economic Zone as a multi-product zone of 49.90 hectares, notified on 1 November 2000.

The same list shows GIDC's Surat Apparel Park at village Sachin, Choryasi taluka, notified for apparel on 31 January 2005. Part of it was de-notified in 2021, leaving 21.26 hectares under SEZ status. GIDC's October 2026 estate table lists the Surat Apparel Park (Sachin) with 103 plots, 82 of them allotted.

If your unit is inside a zone, ask the installer to confirm early which approvals the zone administration needs for rooftop work, along with the power company's net metering steps. Do not assume the paperwork is identical to a plot in the open estate.

Dye houses, looms and when they use power

Processing houses here heat with boilers and thermic fluid heaters, so their electric load is the motors around them: jet and jigger machines, stenters, pumps, blowers and effluent handling. Loom sheds draw a steady load for as long as the looms run, often over two or three shifts.

Solar only produces in daylight. On an LTMD or HTP-I connection, GERC's rules set solar off only against power used between 7 am and 6 pm, so a night shift gains nothing from the panels. A sensible system is sized to the unit's steady daytime base load rather than to the whole monthly bill.

If your unit keeps a diesel generator as backup, tell the installer: a grid-tied solar system switches itself off during a grid outage for safety, and it will not run alongside a DG set unless the installer adds controls designed for that.

• Pull 12 months of bills and note your tariff category before any survey.
• Check daytime motor load against likely solar output using meter data; in a busy processing house the load is often the larger of the two.
• Unused surplus is not carried forward; the DISCOM buys it at a rate linked to recent state solar tenders, usually well below what you pay, so do not oversize.

Fumes, effluent and the roof itself

GIDC lists common effluent treatment (CETP) facilities in the Sachin and Pandesara estates, a sign of how much wet processing goes on here. Near dye and chemical units the air carries moisture and fumes that eat ordinary steel and dull glass faster than in a clean estate.

Ask for hot-dip galvanised or coated mounting rails, stainless steel fasteners and junction boxes with a proper seal. Plan module cleaning more often than the usual guidance, and put it in writing who will do it and how water drains off the roof.

Older sheds in the estate need a closer look. Asbestos-cement sheets cannot be walked on or drilled freely, and rusted purlins may not take the extra weight and wind pull. A good installer climbs up, checks the sheets, purlins and leaks, and tells you if part of the roof needs replacing first. South Gujarat's heavy monsoon makes flashing at every bolt through the sheet important.

Rented sheds and shared roofs

If you rent your shed, GERC's rules allow rooftop solar on rented premises, and a developer-owned system on your roof is also allowed, but you need the owner's written consent. Group or virtual net metering is not in force in Gujarat (GERC published draft regulations in 2026 that propose it), so on a roof shared by several galas each system usually ties to one meter. Agree on who uses which part of the roof before anyone signs.