What is a solar EPC company, and why it matters who builds your system

When you start looking for someone to install solar, you will meet manufacturers, dealers, distributors, electricians, "solar consultants" and companies that call themselves "solar EPC". It is not always clear who does what, or who is responsible if something goes wrong. Understanding what an EPC company is helps you know what you are buying, and what you should expect from whoever builds your system.

What EPC means

EPC stands for Engineering, Procurement and Construction. A solar EPC company takes responsibility for delivering a complete, working solar system:

• Engineering: assessing the site, designing the system, sizing it, and producing the electrical and structural design.
• Procurement: choosing and buying the panels, inverter, structure, cables, protection devices and everything else.
• Construction: installing the system, connecting it, testing it, getting approvals and handing it over working.

The key word is responsibility. An EPC company is accountable for the whole system, not just one part of it.

How an EPC company differs from other solar businesses

Panel manufacturers

Manufacturers make panels (and sometimes inverters). Most do not install systems on individual roofs themselves; they sell through distributors, dealers and EPC companies.

Distributors and dealers

Distributors and dealers sell equipment. Some also install, but their focus is the sale of products. When something goes wrong, responsibility can be split between the dealer, the manufacturer and whoever did the installation.

Electricians and small installers

Independent electricians may install solar as part of wider electrical work. Quality varies widely, and design, approvals and after-sales may not be covered.

EPC companies

An EPC company designs, sources, builds and commissions the whole system, and stands behind it. You have one point of responsibility for design, equipment choices, installation quality, approvals and after-sales service.

What each stage involves

Engineering

Good engineering is invisible once the system is built, but it decides how well the system performs for 25 years. It covers:

• Site assessment: roof type and strength, orientation, shading through the day, wind exposure, and your electricity connection and sanctioned load.
• Consumption analysis: sizing the system from your actual bills, not from a package.
• System design: panel layout, string configuration, inverter choice, cable sizing, protection and earthing.
• Structural design: a mounting structure engineered for the roof and wind loads, at a suitable tilt and orientation.
• Electrical design: a single-line diagram showing how everything connects.

See our guides to solar panel tilt angle and orientation and the solar panel wiring diagram for what good design looks like.

Procurement

Procurement is about choosing equipment that suits the design and will last:

• panels from established manufacturers, with clear warranties;
• an inverter suited to the system and your needs;
• a galvanised, wind-rated mounting structure;
• correctly sized solar cable, quality connectors, distribution boxes, breakers and surge protection;
• earthing and lightning protection materials.

This is where cheap installations often cut corners, because most buyers never see the cable, connectors or earthing.

Construction

Construction turns the design into a working system:

• installing the structure, sealed against leaks;
• mounting the panels;
• running cable in protective conduit;
• installing the distribution boxes, inverter, earthing and lightning protection;
• testing and commissioning;
• getting DISCOM approval, inspection and net metering;
• handing over, with an explanation of how to monitor and look after the system.

Why the EPC model matters to you

One point of responsibility

If output is low or something fails, you call one company. There is no passing the problem between a dealer, a manufacturer and an electrician.

Design and installation match

The same people who design the system build it, so the design reflects what can actually be built well on your roof.

Quality of the invisible parts

An EPC company responsible for the whole system has a reason to get the structure, cabling, earthing and protection right, because problems with those parts come back to them.

Approvals handled

DISCOM feasibility, inspection and net metering can be confusing and slow. An EPC company handles them as part of delivering a working system.

After-sales service

A complete system needs cleaning, checks and occasional repairs over 25 years. An EPC company that installed it knows exactly how it was built.

EPC for homes, businesses and large projects

The EPC approach applies at every scale:

• Homes: a 3 to 5 kW rooftop system. See our home solar cost guide.
• Businesses and institutions: hospitals, schools, offices and factories. See our guide to commercial rooftop solar.
• Large projects: megawatt-scale plants. See our guide to 1 MW solar power plant cost.

The engineering becomes more complex as size grows, but the principle is the same: one company responsible for delivering a working system.

What to check before hiring a solar EPC company

1. Track record: how long they have been installing, how many systems, and examples similar to yours.
2. Local presence: an office near you, and staff who will be around for after-sales.
3. Design detail: will they show you the layout, single-line diagram and equipment list?
4. Equipment by make and model: not just "tier-1 panels".
5. Structure and protection specification: wind rating, galvanising, earthing, lightning protection and surge protection.
6. Who does the work: their own team, or subcontractors?
7. Approvals: do they handle DISCOM feasibility, inspection and net metering?
8. Warranties: product, performance, inverter and workmanship, in writing.
9. Maintenance: what visits include, how often, and response time.
10. Honesty about the subsidy: are they a registered PM Surya Ghar vendor with your DISCOM? Do they quote prices before or after subsidy, and do they explain the conditions?

About the PM Surya Ghar subsidy and EPC companies

Being an EPC company is not the same as being a registered PM Surya Ghar vendor. The subsidy is paid only for systems installed by a vendor registered with the consumer's DISCOM on the National Portal. Origian Power is an EPC company, but it is not a registered PM Surya Ghar vendor, so a system we install does not qualify for that subsidy. We say this before quoting, and we always quote the full price. If the subsidy is important to you, ask every EPC company whether they are registered with your DISCOM, and check the official portal. See our subsidy guide.

Origian Power as a solar EPC company

Origian Power is a solar Engineering, Procurement and Construction company working across Telangana and Andhra Pradesh. We take responsibility for systems from design to switch-on and beyond.

Our team: Sohith, our Managing Director, has 10 years in the solar power industry. Our nine-person team includes managing partners leading sales and procurement, heads of sales for Telangana and Andhra Pradesh, a head technician, documentation and finance staff, and office staff.

Our offices: two in Hyderabad (Hitech City and Nizampet) and one in Anantapur.

Our track record: operating since 2020, with more than 300 installations and over 2,000 kW commissioned, including residential systems and commercial hospital installations.

Our process: a first meeting to explain how the system works, a site visit, a quotation, document collection, advance payment or loan processing, installation, DISCOM documentation and approval, synchronisation and switch-on. This typically takes 10 to 15 days end to end.

Our build standard:

• panels from Renewsys, Adani, Waaree and Tata; inverters from Growatt, Solis and Goodwe;
• hot-dip galvanised structures with stainless steel bolts, rated to 150 km/h wind;
• dedicated lightning-arrestor earthing in its own pit, and copper equipment earthing bonding every frame;
• surge protection on both DC and AC sides, in Siemens or Finder distribution boxes;
• Stäubli-grade MC4 connectors and Polycab (or equivalent) cable in UPVC conduit.

Our warranties: 10-year product and 25-year performance warranty on panels; 5 to 10 years on inverters depending on brand; 5 years on our workmanship.

Our after-sales: maintenance visits every three months, and a 48-hour response commitment for reported issues.

You can see the hardware we use on our Built to Last page, or book a free site survey to talk to us about your roof.

What can go wrong without a proper EPC approach

When nobody owns the whole system, these problems are common:

• Design mismatch: panels and inverter that do not suit each other, or strings outside the inverter's voltage window.
• Weak structures: frames that rust or loosen within a few years, or are not rated for wind.
• Hidden shortcuts: thin cables, poor connectors, missing surge protection or shared earthing.
• Approval delays: the owner left to chase the DISCOM for feasibility, inspection and the net meter.
• No after-sales: the dealer says it is the installer's problem, the installer says it is the manufacturer's.

Each of these reduces generation, shortens equipment life or creates safety risks. The EPC model exists to prevent exactly this.

Questions to ask about after-sales

Over 25 years, after-sales service matters as much as installation. Ask:

1. Who do I call if generation drops?
2. How quickly will someone come?
3. What do routine maintenance visits include, and how often?
4. Who handles warranty claims with the manufacturer?
5. Will the company still be around? How long have they been operating, and do they have a local office?

At Origian, maintenance visits are scheduled every three months, and we respond within 48 hours when a customer reports an issue. There is no formal claims form: you call us, and a technician visits to check and fix the problem.

EPC contracts: what should be in writing

Whatever the size of the project, the agreement should state:

• the system size and exact equipment (makes and models);
• the structure specification and wind rating;
• protection and earthing specification;
• the full price, payment stages and what is included;
• who handles DISCOM approvals and net metering;
• timeline;
• warranties for panels, inverter and workmanship;
• maintenance terms.

A clear written scope protects both sides and avoids disputes later.

How the EPC process works, step by step

For a typical rooftop project, an EPC company's work follows a clear sequence. At Origian, it runs like this:

1. First meeting: we explain how the system works, what it can and cannot do, and what to expect.
2. Site visit: we assess the roof, shade, structure, wiring and your connection.
3. Quotation: system size, exact equipment, structure and protection specification, and full price.
4. Document collection: electricity bill, property documents and identity documents.
5. Advance payment or loan processing.
6. Installation: structure, panels, cabling, distribution boxes, inverter, earthing and lightning protection.
7. DISCOM documentation and approval: the net metering application and inspection.
8. Synchronisation and switch-on: the system is connected and handed over.

This typically takes 10 to 15 days end to end. DISCOM timelines can vary.

EPC for commercial and institutional clients

Commercial projects add some extra steps:

• load and bill analysis over 12 months or more, including demand charges where relevant;
• structural assessment of larger roofs, including metal sheet roofs;
• coordination with facilities teams so installation does not disrupt operations;
• integration with existing electrical systems, such as generators and UPS;
• reporting: generation data the finance team can track.

See our guide to commercial rooftop solar for more.

How to compare EPC quotes fairly

Quotes from different EPC companies can look alike but differ greatly in what they include. To compare fairly:

• Put them side by side on equipment: panel make, model and wattage; inverter make, model and warranty.
• Compare the structure: material, galvanising, wind rating, tilt and height.
• Compare protection: earthing cable size, a separate lightning earth pit, and SPDs on both sides.
• Compare cabling and connectors: cable make and size, connector brand, conduit.
• Compare what is included: DISCOM approvals, net metering, transport, commissioning.
• Compare after-sales: warranties, maintenance visits and response times.
• Compare the price on the same basis: full price before any subsidy, since subsidy eligibility depends on vendor registration.

A quote that is much cheaper usually differs somewhere on this list. Find out where.

Red flags when choosing an EPC company

Be cautious if a company:

• will not name the exact equipment brands and models;
• quotes "after subsidy" prices without saying whether it is a registered vendor with your DISCOM;
• cannot explain how the system is earthed and protected;
• has no local office or service team;
• pressures you to sign quickly;
• offers warranties only verbally.

How long a solar EPC relationship lasts

Buying a solar system is not a one-time transaction. The panels are designed to produce power for 25 years or more, and the relationship with your EPC company spans much of that time, through warranty claims, maintenance visits, inverter servicing and eventual replacements. That is why the company's stability, local presence and service record matter as much as the price on the day you sign.

EPC and the people who actually do the work

An EPC company is only as good as its team. When you speak to one, ask who will actually be on your roof. Is the work done by the company's own technicians or by subcontractors? Who checks the work before switch-on? Who will come back for maintenance?

At Origian, our team includes a head technician, and we have offices in Hitech City, Nizampet and Anantapur. Our managing director, Sohith, has 10 years in the solar power industry.

What an EPC company cannot promise

A good EPC company is also clear about its limits:

• It cannot control the weather. Generation varies with season and cloud cover; estimates are averages.
• It cannot speed up the DISCOM beyond a point. Approval and inspection timelines depend on the utility.
• It cannot get you a subsidy it is not registered for. PM Surya Ghar is paid only through registered vendors.
• It cannot make panels last forever. Panels degrade slowly; the performance warranty sets the expected output over 25 years.

Be cautious of any company that promises otherwise.

Frequently asked questions

What is a solar EPC company? A solar EPC company handles Engineering, Procurement and Construction: it designs the system, buys the panels, inverter and balance of system, installs and commissions it, and takes responsibility for delivering a working system. You get one point of responsibility for design, equipment, installation, approvals and after-sales service.

What is the difference between a solar EPC company and a solar dealer? A solar dealer mainly sells equipment, and responsibility can be split between the dealer, the manufacturer and whoever installs it. A solar EPC company designs, sources, builds and commissions the whole system and stands behind it, so problems with design or installation come back to one company.

How do I choose a solar EPC company? Check the solar EPC company's track record, local office, design detail, exact equipment makes and models, structure and protection specification, who does the work, DISCOM handling, written warranties, maintenance terms, and whether it is a registered PM Surya Ghar vendor with your DISCOM. Then compare quotes on the same basis.

Does a solar EPC company handle DISCOM approval and net metering? A good solar EPC company should. At Origian, the net metering application and DISCOM coordination are part of the installation, along with documentation, inspection support, synchronisation and switch-on. The whole process typically takes 10 to 15 days end to end, though DISCOM timelines can vary.

Is every solar EPC company a registered PM Surya Ghar vendor? No. Registration as a PM Surya Ghar vendor with a DISCOM is separate from being a solar EPC company. Origian Power, for example, is an EPC company but not a registered PM Surya Ghar vendor, so systems we install do not qualify for that subsidy. Check the official portal's vendor list.

What warranties should a solar EPC company give? A solar EPC company should give separate written warranties for the panels (product and performance), the inverter, and its own workmanship. At Origian, panels carry a 10-year product and 25-year performance warranty, inverters 5 to 10 years depending on the brand, and our workmanship 5 years.

How long does a solar EPC company take to install rooftop solar? At Origian, a rooftop solar project typically takes 10 to 15 days end to end, from document collection through installation, DISCOM documentation and approval to synchronisation and switch-on. Larger commercial projects take longer, and DISCOM timelines can vary, so ask any installer for a written timeline.