Longi Solar Panels Cornwall.
Longi is one of the world's largest solar manufacturers, and their Hi-MO panels use back-contact cell technology that keeps performance stable even as the panel heats up on a sunny Cornish roof. We fit them as part of a fully surveyed, MCS certified installation, designed around your roof's actual shape and shading rather than a standard template.
Scale you can rely on.
World's Largest Manufacturer
LONGi is the largest solar panel manufacturer in the world by output, and that scale matters for homeowners as much as it does for utility-scale solar farms. It means deep investment in research, consistent manufacturing quality, and a panel that's been tested and installed at a volume few other brands can match, with over 110GW annual production capacity.
Hi-MO Efficiency
Their Hi-MO series uses monocrystalline PERC and back-contact cell technology to push efficiency to around 22.8%, with a low temperature coefficient that helps performance hold up better on warm days than older panel designs. For Cornwall roofs, that consistency matters more than a headline efficiency number. LONGi panels are built to perform reliably through the county's mix of bright coastal sun, salt-laden air and frequent cloud cover, not just in laboratory conditions.
25-Year Warranty
LONGi backs every panel with a 25-year product and performance warranty, and because they manufacture at such scale, replacement parts and warranty support are rarely an issue years down the line, a real consideration when you're choosing a system meant to last a quarter of a century on your roof.
Fully Certified Installation
Longi backs its panels with some of the longest warranties in the industry, up to 30 years on power output, which matters most on larger arrays where long-term reliability is the whole point. Get in touch for a free quote and we'll talk through whether Longi is the right fit for your roof.
St Austell
13x Longi 435W Panels
Built by the world's largest manufacturer.
World’s Largest Manufacturer
Over 110GW annual production capacity, backed by serious manufacturing scale and quality control.
Hi-MO Efficiency
Monocrystalline PERC cells rated around 22.8% efficiency, with strong performance in variable light.
25-Year Warranty
Full product and performance warranty, backed by a manufacturer built to still be here in 25 years.
Proven Reliability
A bankable, widely-installed panel with a strong real-world track record, not just lab figures.
Is Longi right for you?
Longi suits you if you value manufacturer scale and long-term support, a proven, bankable panel from the world's largest producer, backed by the reassurance that comes with that size.
More ways we can help.
Common Questions
Scale matters for warranty confidence and parts availability, and a manufacturer at Longi's size is well-positioned to support panels for the full 25-year warranty period.
Yes, Longi's Hi-MO efficiency ratings are competitive with premium brands, so they perform well even on more limited roof space.
I cannot recommend Holloway Electrical highly enough. From the planning of our solar and battery installations through to the final commissioning Jamie's took care of everything. Organised other trades to assist, explained everything that was going on and completed the job on time as promised to an exceptional standard, I could not be happier.
We experienced a very friendly and helpful service from Jamie with our new kitchen electrics. We would highly recommend his services.
We are so pleased with the work that Jamie completed for us today, supplying power to our apartment garage and installing sockets and EV charger. The quality of the work is outstanding. I highly recommend Holloway Electrical Ltd, definitely our electrical professional for all future requirements!
Hi Jamie, Kieran did a great job and we are both very pleased with it. Thank you very much. I would like to discuss with you the electrical box in the kitchen which will need to be replaced. PEH
A lovely local company to deal with. Efficient and left everything clean and tidy. Highly recommend.
Great communication, excellent service, great price, 100% recommend.
We had several quotes from Electricians to install our EV charger which varied dramatically. Jamie’s quote was by far the most reasonable and he was the only one who bothered to come to our home and look at the charger etc. before taking on the job. He arrived on the agreed date of installation and was personable, efficient and tidy. I would have no hesitation in recommending Jamie and would be happy to call on his services again in the future.
Jamie provided us with a personable, friendly and efficient service when installing our new EV charger. I would have no hesitation in recommending him.
I cannot recommend Holloway Electrical highly enough. From the planning of our solar and battery installations through to the final commissioning Jamie's took care of everything. Organised other trades to assist, explained everything that was going on and completed the job on time as promised to an exceptional standard, I could not be happier.
We experienced a very friendly and helpful service from Jamie with our new kitchen electrics. We would highly recommend his services.
We are so pleased with the work that Jamie completed for us today, supplying power to our apartment garage and installing sockets and EV charger. The quality of the work is outstanding. I highly recommend Holloway Electrical Ltd, definitely our electrical professional for all future requirements!
Hi Jamie, Kieran did a great job and we are both very pleased with it. Thank you very much. I would like to discuss with you the electrical box in the kitchen which will need to be replaced. PEH
A lovely local company to deal with. Efficient and left everything clean and tidy. Highly recommend.
Great communication, excellent service, great price, 100% recommend.
We had several quotes from Electricians to install our EV charger which varied dramatically. Jamie’s quote was by far the most reasonable and he was the only one who bothered to come to our home and look at the charger etc. before taking on the job. He arrived on the agreed date of installation and was personable, efficient and tidy. I would have no hesitation in recommending Jamie and would be happy to call on his services again in the future.
Jamie provided us with a personable, friendly and efficient service when installing our new EV charger. I would have no hesitation in recommending him.
Get your free Longi panel quote.
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Serving homes and businesses across Cornwall.
Based in St Austell, we install throughout the following towns and the surrounding villages.
