Longi Solar
Hi-MO 6
The world's bestselling N-type TOPCon panel. 435W, 22.0% efficiency, 30-year performance warranty.
£95 per panel
How it scores
Scores based on published manufacturer specifications and weighted criteria — not lab testing. Methodology.
Specifications
- Cell type
- TOPCon N-type
- Watt peak
- 435
- Weight kg
- 22.5
- Dimensions mm
- 1762x1134x30
- Efficiency %
- 22
- Degradation % years
- 0.4
- Warranty product years
- 12
- Warranty performance years
- 30
- Temperature coefficient %
- -0.29
What I noticed
Longi is the world's largest solar panel manufacturer and the Hi-MO 6 is their flagship N-type TOPCon module. At 435W and 22.0% efficiency, it outperforms most PERC panels at a price premium that has narrowed considerably as TOPCon manufacturing has scaled up. The 30-year performance warranty — covering the degradation curve — is one of the strongest available at this price point.
N-type TOPCon cells degrade at roughly 0.40%/year versus PERC's 0.55%/year. Over 25 years that difference compounds to about 5% more output from a TOPCon panel. On a 12-panel array, that's roughly one panel's worth of extra generation by year 25 — real money at current electricity prices.
Who it suits
The Hi-MO 6 is a strong choice for most UK installs where you want a step up from commodity PERC without paying for premium HJT. The wide installer base in the UK means competitive installation quotes are easy to find. For south-facing unshaded roofs, this is the sweet spot between efficiency and cost.
What I'd watch for
The 12-year product warranty is shorter than Panasonic or REC — if you're in a roof space that's expensive to access, a 25-year product warranty may justify the premium. Confirm the exact model variant with your installer — Longi releases multiple Hi-MO 6 sub-variants at different wattages.
