Across India, an estimated 9 million farmers still depend on diesel pumps because their fields sit kilometres from the nearest grid line. A 5 HP (horsepower) diesel pump burns roughly 3 litres of diesel per hour. At the 2026 retail rate of ₹85 per litre, that is ₹255 every hour of irrigation — and ₹1.85 lakh every year on a typical 4-hour-per-day, 255-day season. The PM-KUSUM scheme (Pradhan Mantri Kisan Urja Suraksha evam Utthaan Mahabhiyan) was built specifically to break this cycle. Component B of KUSUM replaces a working or scrapped diesel pump with a fully off-grid solar pump and covers up to 90% of the cost through central and state subsidies combined.
This guide is the operational manual we hand to farmers on a Heaven Green Energy site visit — the 4-step replacement path, the documents to pre-stage, the system sizing chart against borewell depth, the scrap and disposal rules every State Pollution Control Board now enforces, and the diesel-savings math that turns a ₹3 lakh quote into a 1-to-3-year payback.
Direct answer. Under PM-KUSUM Component B (2026), a farmer replacing a diesel pump installs a standalone solar pump of equivalent HP, claims 30% central subsidy from MNRE, 30% state subsidy, and pays only the remaining 30–40% (often reduced to 10% for SC/ST and small holders). A 5 HP system costs ₹3–3.5 lakh; farmer share drops to ₹50,000–₹1.5 lakh; diesel savings of ₹1.85 lakh/year deliver a 1–3 year payback. Heaven Green Energy is empanelled across Rajasthan, Maharashtra, and Madhya Pradesh.
If your borewell is currently powered by a Kirloskar, Honda, or Field Marshal diesel set and your nearest 11 kV line is more than 300 metres away, Component B is built for you. The bridge below moves from “why now” to the exact application sequence, sizing, and disposal compliance you will be asked about at the District Agriculture Office.
Why Farmers Are Replacing Diesel Pumps with Solar
Three forces have aligned in 2026 that did not exist five years ago. Diesel is no longer the path of least resistance for an off-grid farm.
The first is fuel cost. Retail diesel touched ₹85/L across most Indian states in early 2026, with rural pumps frequently dispensing at ₹88–₹91/L because of haulage. A decade ago diesel sat near ₹50/L and the economics of a solar pump did not close; today the comparison is one-sided.
The second is KUSUM subsidy depth. Component B started in 2019 with a 30% central + 30% state stack — leaving 40% to the farmer. By 2026, most major agricultural states (Rajasthan, Maharashtra, Madhya Pradesh, Haryana, Uttar Pradesh) have layered additional 10–30% subsidy for small farmers, SC/ST holders, and tribal districts, taking the farmer share down to a single-digit percentage in several pockets.
The third is technology maturity. The BIS standard IS 17385 for solar submersible pumps, the Ministry of New and Renewable Energy (MNRE) ALMM (Approved List of Models and Manufacturers) register for modules, and the field-proven track record of brushless DC (BLDC) motor controllers mean a solar pump installed in 2026 carries a 5-year comprehensive warranty and a 25-year panel warranty — figures no diesel pump has ever matched.
For the full national framework around Component A, B, and C, see our PM-KUSUM complete guide. For the head-to-head economic comparison, the diesel vs solar pump ROI deep-dive lays out a 10-year cashflow at 3 HP, 5 HP, and 7.5 HP.
The 4-Step Diesel-to-Solar Replacement Path under KUSUM
This is the named framework we use across every Component B project. Four sequential steps, each with its own document set and timing window. Treat it as a checklist.
Step 1: Pre-Application Pump Audit and Land Document Pull (Week 1)
Before opening the state KUSUM portal, close out four things.
Diesel pump audit. Record the current diesel pump make, model, HP rating, year of purchase, and average diesel consumption (litres/day) over the last season. This data feeds the savings calculation that the subsidy office uses to validate your application. Take photographs of the pump, the diesel storage drum, and the borewell head.
Borewell depth measurement. A licensed driller’s report or your original borewell completion certificate gives the static water level (depth to the water table) and dynamic water level (depth while pumping). These two numbers determine the solar pump HP and pipe length — get it wrong and the pump either burns out or runs dry.
Land ownership documents. Pull a fresh 7/12 extract (Maharashtra), Jamabandi or Khasra Khatauni (Rajasthan, Madhya Pradesh, Haryana, UP), Pattadar Passbook (Telangana, Andhra Pradesh), or RTC (Karnataka). The land record must be in the applicant’s name; if it is jointly held, all co-owners sign a consent form. Land must be agricultural classified.
Aadhaar–bank seeding. The KUSUM subsidy is released via Direct Benefit Transfer (DBT). Your bank account must be seeded with your Aadhaar number through the UIDAI Aadhaar seeding portal or at a bank branch.
Step 2: Portal Application and Vendor Empanelment (Week 2)
Each state runs its own Component B portal under the central PM-KUSUM umbrella. Open your state portal, register with your Aadhaar-linked mobile number, and trigger an OTP.
- Select state and district.
- Select Component B (standalone off-grid solar pump).
- Enter HP requirement (the pump sizing table below maps this to borewell depth).
- Upload Step 1 documents (land record, borewell certificate, diesel pump photos, Aadhaar, bank passbook).
- Select a vendor from the state’s empanelled list. The state DISCOM (distribution company) or State Renewable Energy Development Agency publishes the list quarterly.
- Submit. The portal generates an application reference number — save it.
Heaven Green Energy is empanelled in Rajasthan (RREC), Maharashtra (MEDA), and Madhya Pradesh (MPUVNL). State-specific application notes are in our KUSUM Rajasthan guide and the KUSUM Maharashtra 2026 application.
Step 3: Technical Sanction, Subsidy Order, and Farmer Share Payment (Week 3–6)
The state nodal agency reviews the application against four checks:
- Land record validity and applicant ownership.
- Borewell depth and water yield certificate (matches sizing rules).
- Distance from nearest 11 kV electricity line — must be more than 300 metres for Component B eligibility (close-to-grid farms get pushed to Component C).
- Diesel pump existence proof (photographs, fuel purchase receipts, or driller’s certificate).
On approval, the agency issues a Technical Sanction Letter and the Subsidy Order showing the exact ₹ figure for central, state, and farmer shares. The farmer pays his/her share into the agency’s escrow account or directly to the empanelled vendor — depending on the state model. Payment receipt is uploaded back to the portal.
Step 4: Installation, Commissioning Inspection, and Subsidy DBT (Week 7–10)
After farmer-share payment, the vendor schedules installation. Site work covers panel mounting structure (typically galvanised steel on a 4 metre × 4 metre concrete foundation), DC cabling, controller mounting in a weatherproof enclosure, submersible pump descent into the borewell with appropriate cable and pipe, and earthing per IS 3043.
A typical 5 HP system installs in 3–5 working days. After commissioning, the state inspector visits for a physical audit — checking panel count and model serial numbers against the ALMM register, inverter and controller serial numbers, pump HP rating, water discharge test, and earthing resistance. Once the inspection report is filed, the central and state subsidies are released via DBT within 30–45 days to the vendor (or the farmer, if the upfront-payment-then-reimbursement model applies in that state).
The old diesel pump must be scrapped and an End-of-Life (EoL) certificate filed before the subsidy is released — covered in Section 9 below.
Subsidy Eligibility for Diesel-Pump Replacement
Component B is restricted to off-grid agricultural use. The eligibility rules are tighter than rooftop schemes because the central scheme is designed to address grid extension gaps, not to substitute already-connected pumps.
| Criterion | Requirement | Source |
|---|---|---|
| Land ownership | Agricultural land in applicant’s name (or jointly held with consent) | MNRE KUSUM guidelines |
| Land area | Sized to support pump output — typically 2–10 acres per pump | State nodal agency norms |
| Distance from 11 kV line | Greater than 300 metres (close-to-grid is routed to Component C) | MNRE 2024 amendment |
| Borewell | Existing functional borewell with water yield certificate | State guidelines |
| Existing pump | Diesel pump (preferred) or no existing pump; grid-connected pumps are routed to Component C | KUSUM Component B charter |
| Aadhaar–bank seeding | Required for DBT release | DBT Mission |
| Vendor | MNRE-empanelled and state-empanelled | State RE agency list |
The category-based subsidy stack varies by state but the central template is:
| Farmer category | Central subsidy (MNRE) | State subsidy (typical) | Farmer share |
|---|---|---|---|
| General farmer | 30% | 30% | 40% |
| Small / marginal farmer | 30% | 50% | 20% |
| SC / ST farmer | 30% | 60% | 10% |
| Tribal sub-plan district | 30% | 60% | 10% |
| Women-headed household (select states) | 30% | 50–60% | 10–20% |
For a stepwise application walkthrough including state-specific portal screenshots, see our Component B application guide. If your farm is within 300 metres of an 11 kV line, the grid-tied path is a better fit — read the Component C grid-tied pump guide.
System Sizing — Matching Solar to Existing Pump HP and Borewell Depth
Two variables drive sizing: the existing diesel pump HP rating (which sets the irrigation throughput your land needs) and the borewell depth (which sets the pumping head the motor has to overcome). Get either wrong and you either under-irrigate or burn the controller.
Pump HP to Solar System (kWp) Conversion
A solar pump system is sized as solar panel watt-peak (Wp) per HP of pump. The general thumb-rule under MNRE guidelines is 1.5 kWp solar per 1 HP pump to handle the morning/evening light dips and the motor’s surge current.
| Diesel pump HP | Equivalent solar HP | Recommended solar kWp | Indicative system cost |
|---|---|---|---|
| 2 HP | 2 HP | 3 kWp | ₹1.5–₹1.8 lakh |
| 3 HP | 3 HP | 4.5 kWp | ₹2–₹2.5 lakh |
| 5 HP | 5 HP | 7.5 kWp | ₹3–₹3.5 lakh |
| 7.5 HP | 7.5 HP | 11.25 kWp | ₹4.5–₹5.5 lakh |
| 10 HP | 10 HP | 15 kWp | ₹6–₹7 lakh |
Borewell Depth to Pump HP Mapping
Borewell static water level (the depth you draw from at rest) is the more important number than total bore depth — a 300 ft bore with water at 40 ft is a shallow pump scenario.
| Static water level | Recommended pump HP | Typical use case |
|---|---|---|
| 0–50 feet | 3 HP | Small farm, vegetable patch, drip irrigation 2–3 acres |
| 50–100 feet | 5 HP | Standard 5–7 acre farm; the most common KUSUM B sizing |
| 100–200 feet | 7.5 HP | Deep table in semi-arid zones — west Rajasthan, north Karnataka |
| 200–300 feet | 10 HP | Very deep table; requires high-head submersible with multi-stage impeller |
| 300+ feet | Custom design | Solar may not be cost-effective; consult sizing engineer |
Get a free sizing audit. Our field engineers measure your borewell depth, water yield, and current diesel consumption — then send a written sizing report inside 48 hours. Get your free quote →
For a live calculation against your own bore depth and acreage, use the Heaven Green solar calculator and choose “agricultural pump” as the use case.
Diesel Pump Scrap and Disposal Norms
This is the step most farmers overlook — and it is the single most common reason that KUSUM Component B subsidies are held up. The old diesel pump must be legally scrapped and certified before the subsidy DBT is released.
The rules trace to the Central Pollution Control Board (CPCB) framework on End-of-Life Vehicles (EoLV) and small diesel engines, layered with state-specific procedures.
Step A — Drain residual fuel and lubricants. Drain the diesel tank, engine oil, and gearbox oil into recyclable containers. Hand them to a registered hazardous waste handler — a list is maintained by the State Pollution Control Board.
Step B — Hand the pump to a registered scrap dealer. The diesel engine, fuel tank, and pump housing go to a Bureau of Indian Standards (BIS) registered scrapper. Scrap value typically ranges ₹3,000–₹8,000 depending on age (under 5 years fetches the top of the range) and copper-winding weight. Get a stamped scrap receipt showing weight and value paid.
Step C — Obtain the End-of-Life certificate. The scrap dealer files a digital EoL certificate with the State Pollution Control Board within 7 days. This certificate is what you upload to the KUSUM portal to release the subsidy DBT.
Step D — Inform your fuel dealer. If you held a bulk diesel storage permit (most farmers with 200 L+ drums do), notify your fuel dealer in writing and surrender the permit. This prevents the permit being misused.
Watch out
Several farmers attempt to keep the old diesel pump "in case the solar fails." The KUSUM rules explicitly prohibit this — the diesel pump must be scrapped and the EoL certificate filed. If a state inspector finds the diesel pump on site during the commissioning visit, the subsidy claim is rejected and the farmer pays the full system cost. Heaven Green coordinates the scrap pickup as part of our installation service.
Cost, ROI, and Annual Diesel Savings Math
The arithmetic that closes the decision sits in two numbers — what diesel costs you each year versus what the solar system costs after subsidy. Below is the comparison for the most common KUSUM B sizing (5 HP).
| Line item | Diesel pump (5 HP) | Solar pump (5 HP / 7.5 kWp) |
|---|---|---|
| System / equipment cost | ₹35,000–₹50,000 (new diesel set) | ₹3,00,000–₹3,50,000 (full system) |
| KUSUM subsidy (30% + 30% to 60%) | Not applicable | ₹1.8–₹2.8 lakh |
| Farmer out-of-pocket | ₹35,000–₹50,000 | ₹50,000–₹1.5 lakh |
| Diesel fuel per hour | ₹255 (3 L × ₹85) | ₹0 |
| Daily run cost (4 hours) | ₹1,020 | ₹0 |
| Annual run cost (255 days) | ₹2,60,100 — say ₹1.85 lakh after partial-load adjustment | ₹0 |
| Annual maintenance | ₹8,000–₹15,000 (filter, oil, mechanic visits) | ₹2,000–₹3,000 (panel cleaning) |
| Engine life | 8–10 years (then full replacement) | 25 years panel; 7–10 years pump motor |
| 10-year total ownership cost | ₹19–₹22 lakh | ₹65,000–₹1.8 lakh |
| Payback after subsidy | Not applicable | 1–3 years |
The arithmetic that the District Agriculture Office actually does:
- 5 HP × 3 L/hour = 3 litres consumed per running hour
- 3 L × ₹85 = ₹255 per hour
- 4 hours/day × ₹255 = ₹1,020/day
- ₹1,020 × 255 days/year = ₹2,60,100/year theoretical
- Field-observed real consumption (partial-load, cooler mornings) = ~₹1.85 lakh/year
Take ₹1.85 lakh annual diesel saving, divide by the farmer’s net out-of-pocket. At ₹50,000 farmer share (SC/ST 90% subsidy), payback is 3.2 months. At ₹1.5 lakh farmer share (general category 60% subsidy stack), payback is 9.7 months. Even at the worst case — a general farmer with only 30% central subsidy and no state top-up paying ₹2.1 lakh — payback is 13.6 months.
Verdict. Solar Component B replacement is the only KUSUM stream where the unsubsidised case still makes economic sense. Diesel at ₹85/L combined with 4-hour-per-day run profiles delivers payback under 2 years even without any subsidy. With the 60–90% subsidy stack KUSUM provides, the farmer pays back the out-of-pocket in 3–10 months. Heaven Green’s strong recommendation is full diesel replacement, not a hybrid.
Common Mistakes in Diesel-to-Solar Conversion
Across the Component B projects we have handled in Rajasthan and Maharashtra, these are the six recurring errors. Each one is preventable with a 30-minute pre-check.
-
1
Undersizing the pump for borewell depth. Farmers ask for a 3 HP system to save cost when their 120 ft static water level needs 5 HP. The pump runs but cannot lift the column — irrigation throughput drops 40%. Always size against measured static water level, not against the diesel pump rating.
-
2
Skipping the EoL scrap certificate. The diesel pump must be scrapped via a registered handler with a CPCB-aligned EoL certificate. Without it, the subsidy DBT is held indefinitely.
-
3
Choosing a non-ALMM panel. Some vendors quote Chinese-origin panels not on the ALMM register to undercut on price. State inspectors reject the installation and the subsidy is forfeited. Always confirm the panel model is on the current ALMM list.
-
4
Ignoring water yield certificate. Land record alone is not enough — the borewell water yield certificate is what the technical sanction is built on. Missing this delays approval by 4–6 weeks.
-
5
Applying for Component B when grid is within 300 m. If your nearest 11 kV line is closer than 300 metres, the application is routed to Component C (grid-tied), not B. Submitting under B causes 4–6 week rework.
-
6
Bank not Aadhaar-seeded. The subsidy DBT bounces if the farmer's bank is not seeded with the same Aadhaar number used on the application — the most preventable error in the entire pipeline.
Pros and Cons — Full Replacement vs Hybrid (Solar + Diesel Backup)
A handful of farmers ask whether to keep the diesel pump as backup and add solar in parallel. The KUSUM scheme does not allow this — but a self-funded hybrid is technically possible. Here is the trade-off.
- Pro 60–90% subsidy stack reduces out-of-pocket to ₹50K–₹1.5L
- Pro Zero fuel cost — ₹1.85 lakh/year saving locked in
- Pro 25-year panel warranty, 5-year system warranty
- Pro No engine maintenance — no filters, no oil change, no mechanic visits
- Con No pumping after sunset (battery storage is not part of B)
- Con Monsoon weeks may run at 40–60% throughput
- Pro Diesel backup for cloudy days and night irrigation
- Pro Familiar fallback option
- Con KUSUM subsidy NOT available — full ₹3L cost out-of-pocket
- Con Diesel maintenance continues at ₹8K–₹15K/year
- Con Payback stretches to 6–8 years from solar savings alone
- Con Two systems = two failure modes
The verdict from 200+ Component B installations: full replacement is the right call for 95% of farmers. The cases where hybrid is sensible — large dairy operations needing pre-dawn pumping, cash-crop farms with critical irrigation windows — are better served by Component C grid-tied or by adding a separate battery-backed water tank at a later stage.
How Heaven Green Energy Helps Diesel-Pump Farmers
Heaven Green Energy is MNRE-empanelled and operates KUSUM Component B installations across Rajasthan, Maharashtra, and Madhya Pradesh. We have completed more than 200 diesel-to-solar pump replacements through 2024 and 2025, and our process is built around the four failure points farmers tell us about most often — sizing errors, EoL certificates, ALMM compliance, and DBT-stuck subsidies.
What we handle end-to-end:
- Free pre-application site visit — borewell depth measurement, water yield test, land record verification, distance-to-grid check.
- Document pre-check — land record, Aadhaar–bank seeding, diesel pump photographs, scrap arrangement.
- Portal submission — direct upload through our empanelled vendor login, including state-specific document formats.
- ALMM-listed tier-1 panels — Adani, Waaree, Tata Power Solar — never off-list imports.
- BIS-certified solar pumps — IS 17385 compliant submersibles from Lubi, Shakti, or CRI Pumps.
- Diesel pump scrap coordination — pickup, weight, EoL certificate filing with State Pollution Control Board.
- State inspector liaison — installation handover, commissioning audit, DBT release follow-up.
- 5-year comprehensive system warranty + 25-year panel performance warranty.
Explore the services that match your project:
- PM-KUSUM Component B Application — for off-grid farms.
- PM-KUSUM Component C — for grid-connected farms within 300 m of 11 kV line.
- Rajasthan KUSUM application — state-specific portal walkthrough.
- Maharashtra KUSUM 2026 — MEDA process and subsidy depth.
- Rajasthan DREBP — additional state policy stack.
- Solar Calculator — size your system against your borewell depth in 60 seconds.
To start a Component B replacement file, request a free site visit — our nearest field engineer responds within 24 hours.
Frequently Asked Questions
Can I claim PM-KUSUM subsidy if my diesel pump is still working?
Yes. KUSUM Component B does not require the diesel pump to be broken — it covers replacement of any operational diesel pump powering an off-grid borewell. You apply with the existing pump in place, get technical sanction, install the solar system, and then scrap the diesel pump with an EoL certificate before subsidy DBT is released. Most farmers we work with replace functional diesel pumps that are 3–7 years old.
What is the difference between KUSUM Component A, B, and C for diesel pump replacement?
Component A is for grid-connected ground-mount solar farms (500 kW–2 MW); not relevant to a single farmer with one pump. Component B is the standalone off-grid solar pump up to 7.5 HP — the right fit for farms beyond 300 metres from the nearest 11 kV line and currently running diesel pumps. Component C is for grid-connected farmers who already have an electric pump on the agricultural feeder and want to add solar with grid feed-in. Diesel pump owners on off-grid land go to Component B.
How much does a 5 HP solar pump cost after PM-KUSUM subsidy in 2026?
A 5 HP solar pump system carries an indicative all-in cost of ₹3 lakh to ₹3.5 lakh, covering the 7.5 kWp solar panels, BLDC submersible pump, controller, mounting structure, cabling, and installation. Under the general 60% subsidy stack (30% central plus 30% state), the farmer pays around ₹1.2 lakh to ₹1.4 lakh. Under the small-farmer or SC/ST 90% stack, the farmer share drops to ₹30,000 to ₹50,000.
How long does the KUSUM Component B application take end-to-end?
From portal submission to subsidy DBT release, expect 10–14 weeks for a clean application. Step 1 document prep takes 1 week, Step 2 portal submission is 1 day, Step 3 technical sanction runs 3–6 weeks, Step 4 installation and inspection is 3–4 weeks, and DBT release sits at 4–6 weeks after the commissioning report. Sloppy documentation and missed water-yield certificates can push the timeline to 6 months.
Is battery backup included in KUSUM Component B?
No. Component B funds only the panel array, controller, and submersible pump — there is no battery storage in the subsidy scope. The pump runs only during sunlight hours, typically 6–8 productive irrigation hours per day. Farmers needing 24-hour pumping add an overhead water storage tank (which we recommend at 2× daily irrigation volume) rather than batteries, since storing water is far cheaper than storing electricity for pump duty.
What happens to the old diesel pump after solar installation?
The diesel pump must be legally scrapped with a registered scrap dealer or End-of-Life processor before the KUSUM subsidy DBT is released. The dealer drains residual fuel and lubricant, dismantles the engine, and files an EoL certificate with the State Pollution Control Board within 7 days. Farmers receive a scrap value of ₹3,000–₹8,000 depending on age and copper-winding weight. The certificate is uploaded to the KUSUM portal as the final document.
Can my solar pump run a drip irrigation or sprinkler system?
Yes — and this is one of the better pairings under KUSUM. A solar pump’s variable-speed BLDC controller modulates flow throughout the day, which matches the slower discharge rates that drip and sprinkler heads need. Many state schemes (Rajasthan’s Per Drop More Crop, Maharashtra’s PoCRA) offer additional subsidy for combining KUSUM Component B with micro-irrigation, lowering the farmer share further.
What if my borewell yield drops over time — can the solar pump be upgraded later?
Yes. The solar panel array is overspec’d at 1.5 kWp per HP precisely to handle a 10–15% borewell yield drop over a decade. If yield drops further, the submersible pump head impeller stack can be swapped for a higher-head configuration without replacing panels or controller. The cost of an impeller stack swap is ₹15,000–₹25,000, far less than a fresh installation.
Does the KUSUM subsidy apply if my land is leased rather than owned?
In most states, no — Component B requires the applicant to be the registered landowner. A handful of states (Punjab, Andhra Pradesh) allow long-term lease farmers with notarised lease deeds of more than 10 years to apply with the landowner as co-signatory. Always confirm the state-specific rule with your state nodal agency before starting documentation.
Are loans available to cover the farmer’s share of the KUSUM Component B cost?
Yes. The NABARD refinance scheme and most public-sector banks (SBI, PNB, Bank of Baroda, Canara Bank) offer agricultural term loans up to ₹2 lakh for the farmer share under PM-KUSUM, with interest rates of 4–7% and tenures of 5–7 years. The Kisan Credit Card (KCC) limit is increasingly accepted by Component B vendors. Heaven Green coordinates with our partner banks to pre-approve the farmer share before installation.
