
Solar Panels
JA Solar JAM54D41-445/LB DeepBlue 4.0 All Black
Current-gen N-Type DeepBlue 4.0 platform from world top-5 manufacturer. 445W, 22.3% efficiency, all-black.
£63.40 per panel
How it scores
Scores based on published manufacturer specifications and weighted criteria — not lab testing. Methodology.
Specifications
- Cell type
- N-Type TOPCon (DeepBlue 4.0)
- Watt peak
- 445
- Weight kg
- 22
- Dimensions mm
- 1762x1134x30
- Efficiency %
- 22.3
- Degradation % years
- 0.4
- Warranty product years
- 12
- Warranty performance years
- 25
- Temperature coefficient %
- -0.3
What I noticed
JA Solar is consistently in the global top 5 of solar panel manufacturers by shipped volume, with extensive UK distributor coverage. The JAM54D41-445/LB is their current-generation N-Type DeepBlue 4.0 residential platform — 445W in the all-black variant at 22.3% module efficiency.
DeepBlue 4.0 uses N-Type TOPCon cells, with rectangular wafer geometry that improves packing efficiency within the panel and gives a slightly higher peak output for the same module size compared to standard square-wafer designs. The 12-year product warranty and 25-year performance warranty are standard for the segment.
Who it suits
Homeowners who want a balanced combination of a major established brand, current-generation N-Type efficiency, and strong £/W. JA Solar's UK installer familiarity is excellent and warranty support infrastructure is well-developed.
What I'd watch for
The JAM54D41 range includes multiple variants with different frame colours and back-contact configurations — confirm with your installer that you're specifying the all-black LB variant (vs the silver-frame or black-frame versions). The 12-year product warranty is shorter than premium brands offer.
JAM54D41-445/LB DeepBlue 4.0 All Black head-to-heads
Side-by-side scoring vs each alternative in our shortlist.
Other Solar Panels on my shortlist
Read next
Background reading and decision-tree pages that put this product in context.
Stage 5: Panels and batteries explained
TOPCon vs PERC, efficiency, degradation — the specs that actually matter.
TOPCon vs PERC solar panels 2026
N-type vs P-type: real performance gap and whether the premium pays off.
Solar panel cost UK 2026
What a full installation actually costs in 2026 — and what drives the price.
How many solar panels do I need?
Sizing based on your roof, usage, and whether you want a battery.


