- Component A = steady 25-year income from one DISCOM buyer, if your land sits near a substation.
- Rooftop = faster cash and volume, but you must keep selling.
- Open access = higher value per unit, but charges and customers can change.
- Component A pays less per unit but carries the least sales risk; its main risk is DISCOM payment delay.
- All tariffs, charges and land rules are state-variable estimates — verify against the live tender.
This is a capital-allocation question, not a "best technology" question. PM-KUSUM Component A, rooftop solar and open-access solar all turn sunlight into money, but they earn it in very different ways. The right pick depends on your land, your sales muscle, and how much risk you can hold.
The short answer for a land-owning EPC
If you own farm or barren land near a DISCOM substation and you want predictable income for decades, PM-KUSUM Component A is the natural fit. It hands you a 25-year contract with a fixed tariff and one buyer. You trade a higher per-unit price for safety and a long horizon.
If your strength is selling and installing fast, rooftop gives you more deals and quicker cash. If you have large commercial-and-industrial (C&I) customers, open access can earn the most per unit. Most EPCs should start with the model that matches what they already do well, then add the others.
The three models, in plain terms
Each model answers one question differently: who buys your power, and for how long?
PM-KUSUM Component A
Component A is a decentralised ground-mounted solar plant, usually 0.5–2 MW, built on a farmer's or your own land near a substation. The DISCOM buys all the output at a fixed tariff set by the tender, under a 25-year power-purchase agreement (PPA). You win the work through a state tender, not a walk-in subsidy. See the Component A developer guide for the full build path.
Rooftop solar
Rooftop solar puts panels on a customer's roof so they use the power themselves and cut their bill. You earn from building the system, and often from service. Income is project-based: you must keep finding new roofs. This is the world of PM Surya Ghar and commercial rooftop.
Open-access solar
Open access lets a generator sell power to a large C&I customer, or to the exchange, over the grid. You pay the grid owner wheeling and banking charges for the transport. The per-unit price can be high, but those charges and the customer relationship can shift over time.
Head-to-head matrix
Here is the same set of questions answered for all three models. Read each row across to see how the choice changes the answer.
Caption: Decision matrix, SuryaHub. Source: framing from MNRE PM-KUSUM guidelines and SECI model documents. Tariffs, wheeling/banking charges and land norms are state-variable estimates — verify against your live tender and state regulator.
How the returns differ
Component A trades a lower per-unit tariff for a longer, surer income. The DISCOM pays the same fixed rate for 25 years, so your model is simple: known tariff times known generation, minus operations and finance cost. The returns calculator guide walks through the maths.
Why rooftop can look richer on paper
On a rooftop, the customer saves the full retail bill rate, which is often higher than a wholesale solar tariff. So a rooftop unit can be "worth" more. But that value sits with the customer, not you — you earn from the build and service, and you must sell the next job to keep earning.
Why open access can pay the most per unit
Open access can fetch a strong per-unit price from a C&I buyer who wants to cut a high commercial tariff. After wheeling and banking charges, the spread can still beat a Component A tariff. The catch is that those charges are set by the state regulator and can rise, squeezing the spread.
Risk and payment security
Each model concentrates risk in a different place, and that should shape your decision as much as the headline return.
- Component A: one buyer for 25 years. The big risk is DISCOM payment delay. A strong PPA and a payment-security mechanism cushion it — read our DISCOM PPA and payment-security guide.
- Rooftop: many small customers. The risk is churn and default — customers who delay payment or never come back for service.
- Open access: a few large customers. The risk is charge changes and customer churn — a regulatory order or a lost contract can hit your spread fast.
Component A spreads its single risk across 25 years, so a strong, financially healthy DISCOM makes it the steadiest of the three. Check the paying DISCOM's health before you bid.
Effort and skills each model needs
The work to win is as different as the work to build. Be honest about which muscle your team already has.
Component A is a tender-and-grid game
You compete in a state tender, lock up land near a substation, win the bid, then handle grid connectivity and inspection. The skills are bidding, land paperwork and electrical/grid work — not retail sales. If you cannot manage tenders, this is a steep start.
Rooftop is a sales-and-speed game
Rooftop rewards lead generation, quick quoting and fast installs. You need a sales engine and a crew that can turn around many small sites. Margins are thinner per job, so volume and tight operations matter most.
Open access is a relationship-and-regulation game
Open access needs trusted C&I relationships and the patience to clear regulatory approvals. It is the most paperwork-heavy on the sales side, but a single deal can be large and long.
Which model fits which EPC
Match the model to your strongest asset. The decision is rarely about which solar is "best" — it is about which one fits your land, team and balance sheet.
- You own land near the grid and want annuity income → Component A.
- You have a strong local sales team and want cash flow → rooftop.
- You have big C&I customers and can handle regulation → open access.
- You have land but no tender experience → Component A in RESCO mode, or partner with a developer.
Can you run all three at once?
Yes — and many growing EPCs do. Component A gives steady annuity income, rooftop gives volume and cash flow, and open access gives higher-value deals. Together they smooth out the lumpy nature of tender-only work.
The hard part is running three different workflows — three sales motions, three build processes, three billing models — without dropping a step. That is an operations problem, and it is exactly where one system to track everything pays off.
How SuryaHub helps you compare and run all three
SuryaHub runs Component A tenders, rooftop jobs and open-access deals on one platform, so you can compare returns and manage the work side by side. The government-workflows module tracks each PM-KUSUM tender, land file and grid approval, while project management runs every build to schedule. SuryaHub is pre-revenue; the only real pilots are Suryantra Energy and RGESPL, and the figures here are scheme facts and estimates, not guarantees.
Run Component A, rooftop and open access in one place
See how SuryaHub tracks tenders, jobs and returns side by side.
Related guides
Frequently asked questions
Is PM-KUSUM Component A better than rooftop or open-access solar?+
PM-KUSUM Component A is not strictly better — it suits a different EPC. Component A gives a long, stable 25-year DISCOM contract if you have land near a substation. Rooftop and open-access can pay more per unit but carry sales and customer-churn risk. Match the model to your land, skills and risk appetite.
Does Component A pay more than open-access solar?+
Component A usually pays a lower per-unit tariff than open-access solar, but it removes the marketing and customer-churn risk because the DISCOM buys all the power for 25 years. Open-access can earn more per unit yet faces changing wheeling and banking charges. Both tariffs and charges are state-variable — verify the current figures.
What is the main risk of PM-KUSUM Component A?+
The main risk of PM-KUSUM Component A is DISCOM payment delay, since one government buyer pays you across 25 years. A strong power-purchase agreement and a payment-security mechanism reduce this risk. Always check the paying DISCOM's financial health and the security cover before you bid on a Component A tender.
How much land do I need for PM-KUSUM Component A?+
PM-KUSUM Component A plants are typically 0.5 to 2 MW and need roughly four to five acres per megawatt, near a DISCOM substation. The exact land and substation-distance rules vary by state tender, so treat any acreage figure as an estimate and confirm it against the live request-for-selection for your state.
Can one EPC do Component A, rooftop and open-access together?+
Yes, an EPC can run PM-KUSUM Component A, rooftop and open-access solar together, and many growing EPCs do. Component A gives steady annuity income, rooftop gives volume and cash flow, and open-access gives higher-value deals. The challenge is managing three different sales, build and billing workflows without losing track.
Which solar model gives the most stable income for an EPC?+
PM-KUSUM Component A gives the most stable income because the DISCOM signs a 25-year power-purchase agreement at a fixed tariff, so revenue is predictable for decades. Rooftop and open-access income depends on customers who can leave, default or renegotiate. Stability comes at the cost of a lower per-unit tariff with Component A.
Sources & references
The comparison framing comes from primary scheme and tender sources. Tariffs, open-access charges and land norms vary by state and change over time — confirm the current figures before you commit capital.
- Ministry of New & Renewable Energy (MNRE) ↗
PM-KUSUM Component A guidelines and benchmark figures.
- PM-KUSUM National Portal ↗
Component A tenders, dashboard and state status.
- SECI ↗
Model tender documents and open-access reference rules.
Written by the SuryaHub team · reviewed against MNRE, PM-KUSUM portal & SECI sources · updated 19 June 2026.
Method: The model comparison is built from MNRE PM-KUSUM guidelines and SECI documents and re-checked every 30 days. Tariffs, charges and land norms are state-variable estimates to confirm against the live tender. SuryaHub is pre-revenue; only Suryantra Energy and RGESPL are real pilots.
Change log: 19 Jun 2026 — first published.