Quick Facts
What AMC is
AMC (Annual Maintenance Contract) is a yearly service agreement between a solar plant owner and a service provider (typically the EPC contractor or an independent specialist). The contract defines the maintenance, cleaning, inspection, and repair services that will be provided during the contract year, in exchange for a defined annual fee.
For residential and small commercial solar installations, AMC is the standard mechanism for ongoing plant care. Larger utility and commercial plants use more comprehensive O&M (Operations and Maintenance) contracts instead, which include AMC-equivalent activities plus broader operational scope.
AMC is important because solar plants need regular care to maintain expected performance. Module cleaning, inverter inspection, electrical testing, and minor component replacement all contribute to maintaining Performance Ratio and Availability. Without AMC, soiling, faults, and degradation accumulate, eroding plant economics.
What an AMC covers
A standard residential solar AMC typically includes:
Quarterly module cleaning: Water and soft brush cleaning of all panels.
Monthly or quarterly inverter inspection: Visual checks, fault log review, cooling system check, fan cleaning.
Annual electrical testing: Earthing resistance test, insulation resistance test, string current verification, MPPT efficiency check.
Basic component checks: Wiring connections, MC4 connectors, mounting structure, lightning protection.
Performance verification: Comparing actual generation against expected. Identifying performance issues.
Minor consumables: Fuses, MC4 connectors, small wiring repairs as needed.
Customer reporting: Monthly or quarterly report on plant status.
Phone support: Helpline for customer queries and emergency response coordination.
For commercial AMC, the scope is similar but with more rigorous performance monitoring and faster response times.
Comprehensive vs non-comprehensive AMC
Two main AMC variants exist.
Comprehensive AMC (also called full-coverage AMC): Includes all routine maintenance plus replacement of major components within the contract term. If an inverter fails, the replacement is included. If modules fail, replacement is included. Higher annual fee but no surprise costs.
Non-comprehensive AMC: Covers labour and basic consumables only. Major component failures (inverter, modules) are extra cost beyond the AMC fee. Lower annual fee but potential for significant additional costs.
For Indian residential systems, comprehensive AMC typically costs Rs 3,000 to Rs 5,000 per kW per year. Non-comprehensive AMC typically costs Rs 1,500 to Rs 2,500 per kW per year.
Most customers find the comprehensive AMC the better value when accounting for the risk of major component failure. The 50% to 100% premium for comprehensive coverage is small compared to a Rs 30,000 to Rs 50,000 inverter replacement cost.
AMC cost across plant categories
| Plant Type | Typical Annual AMC Cost |
|---|---|
| Residential basic (non-comprehensive) | Rs 1,500 to Rs 2,500 per kW |
| Residential comprehensive | Rs 3,000 to Rs 5,000 per kW |
| Small commercial (under 50 kW) | Rs 400 to Rs 600 per kW |
| Mid commercial (50 to 500 kW) | Rs 300 to Rs 500 per kW |
| Large commercial (above 500 kW) | Rs 250 to Rs 400 per kW |
For a 5 kW residential system: comprehensive AMC at Rs 4,000 per kW = Rs 20,000 per year. This is 1.5% to 2% of the after-subsidy system cost, similar to insurance premiums.
For a 100 kW commercial: AMC at Rs 400 per kW = Rs 40,000 per year. About 0.7% of system cost.
For larger systems, the per-kW cost declines because fixed costs (vehicle, equipment, monitoring) spread over more capacity.
AMC selection considerations
When choosing an AMC provider, evaluate:
Track record: Years in business, number of customers served, customer references.
Coverage scope: What is included and excluded. Specific to comprehensive vs non-comprehensive.
Response times: How quickly the provider responds to fault calls. 24-48 hours is typical; faster for premium AMC.
Cleaning schedule: Frequency and method. Quarterly is standard; more frequent for dusty locations.
Equipment quality: Tools, vehicles, and trained technicians.
Geographic coverage: Provider’s service area. Local presence is important for fast response.
Warranty support: Coordination with module and inverter manufacturers for warranty claims.
Pricing transparency: Clear breakdown of what is included. Hidden charges for “extras” indicate weaker AMC.
Contract terms: Term length, renewal mechanism, dispute resolution.
What AMC does not cover
Common exclusions in solar AMC:
Damage from natural disasters (cyclone, flood, lightning strike on panels). Covered by insurance instead.
Theft and vandalism. Covered by insurance.
Major civil work (roof repair, mounting structure replacement). Owner responsibility.
System enhancements (adding panels, upgrading inverter). Owner-paid project, not maintenance.
Customer-caused damage (modifications by unauthorised electricians). Voids both AMC and warranty.
Performance shortfall due to grid issues (DISCOM outages, voltage issues). Beyond plant scope.
Knowing exclusions helps set expectations and avoid disputes.
AMC versus warranty
Warranty and AMC are complementary.
Warranty: Manufacturer’s commitment that products will perform per specification for the warranty period. Module warranty typically 10-12 year product, 25-year linear performance. Inverter warranty typically 5-10 years.
AMC: Service provider’s commitment to deliver routine maintenance services. Does not cover defects (warranty does) but covers cleaning and inspection (warranty does not).
A typical solar plant has both: warranty from manufacturers for defects, AMC for routine maintenance. The AMC contractor often also handles warranty claims on the owner’s behalf.
Common AMC mistakes
Skipping AMC to save cost. The first year savings often disappear in restoration costs after problems develop.
Choosing the cheapest AMC without checking scope. Low cost often means non-comprehensive with hidden charges.
Letting AMC lapse. Re-enrolling often requires initial inspection charges or denial of coverage for pre-existing issues.
Not verifying AMC scope before signing. The “AMC” label can mean very different things between providers.
Forgetting documentation. Maintenance logs and component records are valuable for future claims and resale.
Trusting AMC promises without contract details. Verbal commitments are unreliable; written terms govern.
Best practices
For residential CAPEX solar, sign comprehensive AMC with the EPC contractor at installation. Renew annually.
For commercial CAPEX solar, evaluate multiple AMC providers including specialists. Performance-based AMC is preferred.
For new installations, look for AMC bundled with longer initial term (3 to 5 years) at discounted pricing.
Verify the AMC contractor’s empanelment with MNRE and DISCOM for any subsidy-related coordination.
Document all AMC visits, work performed, and component status. The records support warranty claims and asset resale.
For aging plants approaching warranty expiry, consider transitioning from AMC to comprehensive O&M with stronger performance commitments.
Standards and references
AMC practices follow industry conventions rather than formal standards. MNRE guidelines for empanelled installers include AMC obligations. Consumer protection law applies to AMC contracts as service agreements. Some state SERCs include AMC norms in their rooftop solar regulations.
Related glossary terms
- O&M in Solar
- Comprehensive vs Non-Comprehensive AMC
- SCADA in Solar
- Performance Ratio
- Soiling Loss
- Shading Loss
- Availability Factor
Key takeaways
AMC (Annual Maintenance Contract) is a yearly service agreement covering scheduled maintenance and minor repairs for residential and small commercial solar plants. Comprehensive AMC includes major component replacements; non-comprehensive does not. Annual costs in India range from Rs 1,500 to Rs 5,000 per kW for residential and Rs 250 to Rs 500 per kW for commercial. AMC is essential for maintaining solar plant performance over the 25-year operating life. Most customers benefit from comprehensive AMC over non-comprehensive due to the modest premium offset by reduced risk of large repair bills.