Almost every rooftop quote in India today offers one of two panel technologies: Mono-PERC or TOPCon. Both are good. The right one depends on your roof space, your budget and how hot your roof gets.
What's the difference?
Mono-PERC (Passivated Emitter and Rear Cell) has been the industry workhorse for years. TOPCon (Tunnel Oxide Passivated Contact) is a newer design built on n-type silicon that wastes less of the sunlight that hits it. In practice that means TOPCon squeezes a bit more energy out of the same roof area and ages more slowly.
Side by side
| Mono-PERC | TOPCon | |
|---|---|---|
| Typical module efficiency | About 20–21.5% | About 21.5–23% |
| First-year degradation | Around 2% | Around 1% |
| Yearly degradation after that | Around 0.55% | Around 0.4% |
| Performance in heat | Good | Better (loses less power per °C) |
| Bifacial gain (double-glass versions) | Lower | Higher |
| Price per watt | Lower | Slightly higher |
These are typical ranges across leading brands. Always check the exact figures on the datasheet of the specific panel in your quote.
Which should you choose?
Choose TOPCon if:
- Your roof space is limited and you want the most kW from it.
- Your roof gets very hot in summer — TOPCon handles heat better.
- You care most about output over 25+ years; slower degradation adds up.
Choose Mono-PERC if:
- You have plenty of shade-free roof space.
- You want the lowest upfront cost per kW.
What matters more than the cell technology
- A Tier-1 manufacturer with a real presence in India, so warranty claims are honoured.
- The performance warranty (typically 25–30 years) and the product warranty.
- Correct system design: orientation, tilt and shade analysis often matter more than a 1% efficiency difference.
- Installation quality — structure, wiring and earthing.
Saura Energy installs both Tier-1 Mono-PERC and TOPCon panels with up to 22% efficiency, and we'll show you the datasheets side by side for your roof.
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