Factory owners usually want one number. Honestly, the answer is four numbers, you install the smallest one.
Physical cap on roof area. So DISCOM sets a legal ceiling. Daytime machines have a useful limit. shade and structure form a safety cap Ignore either one of them and the plant is either illegal, leaky or full of cheap export.
This is a guide for Telangana Industrial Services under TSSPDCL or TSNPDCL. The method works in other states if you swap the local percentage and kilowatt cap.
Quick Answer Box
Take usable roof in sq m and divide by 12 for a starting kW. Compare that to 80% of the sanctioned load and 500 kw. Then compare with weekday daytime kW Install the lowest figure unless you have storage or a plan for a second shift for the surplus. A good industrial rooftop can be expected to cost around ₹35,000–₹50,000 per kW in 2026. No factory meter for PM Surya Ghar check.
The Four Limits That Decide Capacity
Good. Industrial arrays require approximately 10–14 square meters of unshaded, walkable roof space per kilowatt once row gaps, skylights, HVAC, and parapets are removed. A 6,000 square meter PEB sheet looking empty on a drone shot can yield only 3,000 square meters of usable plane. That is about 215-300 kW, not 500 kW.
Load %: TGERC rooftop rules specify industrial and commercial net-metered capacity to 80 per cent of sanctioned load or contracted demand. A 400 kW sanctioned service can net-meter 320 kW, even with a large roof.
Net metering cap. New net-metered systems are limited to 500 kW. The gross metering can be up to 1 MW. Existing larger net-metered systems were grandfathered in. New multi-megawatt rooftops require a different interconnection path and are slower to approve.
Load day. Solar makes power when the sun is up. The shop is drawing 180kW from 8am to 6pm, and 40kW in the evening. The 400 kW array will export hard at midday, but still import after dark. Those exported units are worth less than the units consumed by the line. Size near the day block unless a battery will move the rest.
The plant with the lowest minimum is the installable plant. Mark all four on the survey sheet. A vendor selling only roof area is selling steel, not a bill reduction.
Worked Sizes Telangana Factories Actually See
A small unit with 150 kW sanctioned load, 1,800 square meters usable roof and 90 kW day load is around 90-120 kW, not 150 kW.
A mid-factory with 600 kW sanctioned load, 8,000 square meters usable roof and 350 kW day load is limited by the day load and then by 480 kW (80 percent). A 350 to 400 kW plant is the practical size.
The first to hit the 500 kW net-metering lid is a big campus with 2 MW contract demand and a warehouse roof of 20,000 square meters. The remaining roof is either storage-charged behind the meter, a separate gross-metered slice if the economics work out, or a future open-access discussion. Files stall by filling 1.5 MW of modules and hoping the circle office will net-meter them.
Rooftop solar for a factory price in 2026
Industrial rooftop pricing is a band, not a sticker price. For Indian C&I work in 2026, turnkey values are frequently in the ₹35,000-₹50,000 per kW range as size goes above 50-100 kW. Metal-sheet PEB with clean access is on the low end. More sit tall RCC, longer AC runs, additional walkways, heavy ballast.
Planning sketches many owners use:
- 50 kW: about ₹20–₹25 lakh
- 100 kW: about ₹38–₹50 lakh
- 250 kW: about ₹90 lakh–₹1.2 crore
- 500 kW: about ₹1.8–₹2.2 crore
A decent Hyderabad PEB roof with a 100 kW plant generally produces between 1.4-1.6 lakh units per annum if it is cleaned and unshaded. At industrial tariffs of Rs 7-8 per unit, that is about Rs 10-13 lakh a year of avoided energy before demand charges and tax. Simple payback on a well matched plant often sits in the 3.5-5 year band. That’s maths of planning. They are replaced by your survey.
Which Solar Panel Is Best for Industrial Use
Which solar panel is best for industrial use if it is a brand slogan, is the wrong question. Looking ahead to 2026, the right specification for a Telangana factory roof will typically be an ALMM-listed N-type TOPCon module in the 545-625 W class, with a performance warranty of 25 years and a named model number on the contract.
TOPCon is more temperature resistant than older polycrystalline and most of the remaining PERC stock. High wattage modules also reduce the number of rails and walking time on a large PEB. Dark sheet roof has limited bifacial gain. Don’t pay a bifacial premium unless justified by the mount and albedo.
Polycrystalline uses less roof space and costs less per watt. On a space-starved factory that is a false economy. It may still appear in old quotations on a large garden. For a 2026 industrial rooftop file that has to interconnect, ALMM listing beats a brochure efficiency decimal.
Also name the inverter family. String inverters with monitoring in industrial plants, not a hybrid box for 200 kW residential.
Table 1: Sizing Constraints versus Typical Factory Outcome
| Factory picture | Roof-limited kW | 80 percent load kW | 500 kW lid | Day-load kW | Sensible install |
| Small shed, 120 kW service | 80 | 96 | 500 | 70 | 70–80 kW |
| Mid PEB, 400 kW service | 280 | 320 | 500 | 220 | 220–280 kW |
| Large warehouse, 800 kW | 700 | 640 | 500 | 450 | 450–500 kW net |
| 2 MW HT campus, huge roof | 1,200 | 1,600 | 500 | 900 | 500 kW net, rest other route |
| Night-heavy process | 400 | 320 | 500 | 80 day | 80–120 kW or add storage |
The last row is where owners overspend. A plating shop that runs at night does not become a 400 kW solar success because the roof is empty.
Commercial Subsidy and Government Schemes, Stated Plainly
Commercial solar power plant subsidy in India is the most meeting time-wasting phrase.
PM Surya Ghar Muft Bijli Yojana provides up to Rs 78,000 on residential connections. A factory meter doesn’t count. Not eligible for a shop on a commercial service. Housing-society common-area CFA is another track, but still not a factory benefit.
The only commercial scheme is accelerated depreciation under the Income Tax Act Section 32. The owner of the plant can generally claim 40 per cent of the depreciation on the solar asset in the first year (half that rate if used for less than 180 days in the financial year). And a ₹20 lakh deduction on a ₹50 lakh plant is ₹5 lakh of tax saved in year one at 25 per cent tax rate. GST input credit may also be available when the output is taxable. MSMEs can be funded by SIDBI and bank energy-efficiency lines. None of these is a cheque of DISCOM.
RESCO or rooftop PPA is a contractual scheme and not a subsidy. You pay by the unit. The builder claims depreciation. You pick it up when there is no capital, not because someone called it a government scheme.
Table 2: What Sets Factory kW, Price and Payback
| Item | Treat as | Do not treat as |
| Roof photograph | Start of survey | Final kW |
| Sanctioned load | 80 percent legal cap | Target size |
| 500 kW rule | Net-metering lid | Ban on all larger BTM |
| ₹/kW band | Planning range | Binding quote |
| TOPCon ALMM module | Interconnection-safe default | Optional luxury |
| PM Surya Ghar | Residential only | Factory discount |
| Accelerated depreciation | Year-one tax shield if you own it | Cash subsidy |
| Annual units ÷ 365 | Rough generation check | Night-load offset |
A solar system for industrial use is therefore a grid tied rooftop plant sized to the four limits, built with listed modules and industrial inverters, filed with TSSPDCL or TSNPDCL and paid back from avoided HT units plus depreciation if you own it. The same logic applies to rooftop solar for a factory in India across all states The percentage changes . The kilowatt limit changes
Before you compare quotes, walk the roof with a tape and a sanction letter. The factory that does this installs 280 kW and saves money. The factory ordering “as many panels as the sheet will hold” buys a fight for feasibility.
People Also Ask
How much rooftop solar can a Telangana factory install?
Minimum usable roof kW, 80% of sanctioned load, 500 kW net-metering capacity and day time process load. Gross metering may go to 1 MW. Separate interconnection plan for larger on-site generation facilities.
Which solar panel is best for industrial use?
A named model, ALMM listed N-type TOPCon module of approx. 545-625 W with 25 year performance warranty for most factory roofs in 2026. Brand ranking matters less than the listing, the heat behaviour and the contract annexe.
What is the rooftop solar for a factory price in 2026?
Industrial turnkey work often sits near ₹35,000–₹50,000 per kW. A 100 kW plant is commonly ₹38–₹50 lakh. A 500 kW plant is commonly ₹1.8–₹2.2 crore. Site access and structure move the number.
Is there a commercial solar panel government scheme?
Not a cash subsidy like PM Surya Ghar. Factories use accelerated depreciation, possible GST input credit and energy-efficiency loans. RESCO is a private contract structure.
Can a factory get commercial solar power plant subsidy in India?
Not the residential CFA. Own the asset and speak to your tax adviser about 40 percent first-year depreciation. Commissioning before the 180-day cut in the financial year preserves the full year-one rate.
How much roof does 100 kW need?
About 1,000–1,400 square metres of usable, unshaded roof, plus access paths. Measure after tanks, monitors and neighbouring shade, not from the building footprint.
Should we install up to the 500 kW cap if the roof allows it?
Only if daytime load and the 80 percent rule also allow it. Empty noon export is a weak use of capital.
