Skip to content
Technology

TOPCon, HJT and Bifacial: What's Worth Paying For

A plain-language look at current module technology and which upgrades make a real difference on an Indian rooftop.

Published 27 April 2026 · 7 min read

From PERC to TOPCon

TOPCon modules add a thin passivating oxide layer that reduces electron losses, delivering roughly one to two percent higher efficiency than mono PERC and a lower temperature coefficient — which matters in Trichy's heat.

Heterojunction and where it fits

HJT modules perform best at high temperatures and degrade slowly, but cost more per watt. On a space-constrained roof where every square foot counts, the premium can be justified; on an open industrial shed it usually is not.

Bifacial needs the right surface

Bifacial modules capture reflected light from behind and can add five to fifteen percent output — but only over a bright, reflective surface with adequate clearance. On a dark low-mounted terrace they add cost with little gain.

Microinverters and optimisers

Where shading is unavoidable or roof faces run in several directions, module-level electronics recover generation that a single string inverter would lose. On a clean unshaded roof, a good string inverter remains the better value.

Ready to cut your electricity bill?

Book a free site survey with our engineers. No obligation, no pressure — just an honest assessment of what solar can do for your roof.