Close this search box.
February 18, 2024

LONGi LR5-54HIB Hi-MO 5 Series Solar Panel Review

Solar review

LONGi Introduction:

Headquartered in China, LONGi is the world’s largest solar panel manufacturer. The company specialises in monocrystalline photovoltaic panels, unlike some other brands which produce cheaper but less-efficient polycrystalline cell technology. More and more companies in the solar industry are now concentrating on the cheaper, but less efficient, polycrystalline type of solar panel, especially for residential solar panels.

The company is rated Tier 1 by Bloomberg: that is from their business analysis and means LONGi has solid financial backing and is not likely to have financial issues, as some other solar panel manufacturers have in the past. This should provide consumers with peace of mind, as their solar panels have a lifespan of 25-30 years and the company is still very much likely to be in business during any warranty period.

LONGi Company Overview:

LONGi Solar was founded in February 2000 as Xi’an LONGi Silicon Materials Corporation. Originally a supplier for other renewable energy companies, it moved into the retail market as solar manufacturers selling its own solar panels globally.

LONGi has nine manufacturing plants, seven of them in China, and the remaining two are based in Malaysia and Vietnam. Quality control is a particular focus for LONGi and they foreground reliability and high consumer satisfaction with their products.

The company also puts a significant amount of resources into research and development. Solar panel technology is a highly competitive sector, and LONGi aspires to be at the cutting-edge of development. Their motto is: “To make the best of solar energy to build a green world.”

LONGi has gained multiple industry awards for its products. On the PVEL Scorecard – a kind of “Which Report” on solar panels – rigorous independent testing gave LONGi panels regular high rankings. This testing ensures that users will be purchasing solar panels which have stood up to harsh environments and so will be able to withstand the sort of stresses that the inclement UK weather can provide.

Build Your Own Solar Quote

LONGi Hi-MO 5 Series of Solar Panels

LONGi has several different ranges of solar panels in its offering. This is the Hi-MO 5 Series, which is suitable for larger residential roof space and smaller commercial buildings. LONGi panels come with a 12 year warranty for materials and processing, and a 25 year warranty for extra linear power output.

The LONGi Hi-MO 5 series features excellent photovoltaic technology embedded in high-quality solar cells, which ensured that LONGi was the winner of the 2021 Intersolar award in the Photovoltaic Category. This series consists of five different panels with power outputs ranging from 390 to 410 watts at maximum power output. Module efficiencies range from 20-21%.

This product range is considered one of the best designs from this manufacturer. Hi-MO 5 panels are fabricated using technological enhancements like bifacial, half-cut and PERC solar cell technology inserted in high-quality monocrystalline silicon (mono c-Si) wafers. This make them high efficiency panels and among the best solar panels on the market for that price point.

Though a gain of 1-2% in real power generated over other panels might seem small, over years of operation, it will add up to a considerable amount of extra electricity output from a LONGi solar system, which means lower costs and better ROI in the long run.

LONGi Hi-MO Main Features

Monocrystalline Wafer Technology

Every solar cell in the Hi-MO 5 range features high-quality P-type monocrystalline silicon wafers with gallium doped silicon cells, which has been shown to be stable, cost-efficient, durable and produces improved efficiency for the module.

2. Half-cut cell manufacturing

This technology uses twice as many half-size cells to power the module, hence the name “half-cut”. The benefits of this are higher efficiency by significantly reducing power losses at the initial stages before the DC current leaves the PV panel.

3. Bifacial

Essentially, both sides of the module generate electricity. This means that the sun’s bountiful energy hitting either face of the panel will create power. This could increase energy production by as much as 30%. The rear side of the panel is carefully protected from the weather so that this configuration will not make it more vulnerable to rain and dust.


LONGi also uses Passivated Emitter and Rear Cell (PERC) technology. This is a long-winded way of saying they add a reflective layer at the rear of the cell, which bounces back unabsorbed solar radiation, increasing efficiency. This is claimed to produce 6% to 12% more energy than traditional solar modules.

5. Reduced Degradation

Hi-MO 5 panels are particularly good in terms of degradation. Like most things, solar panels are subject to wear and tear. Over time, the energy output decline, as the panels become less efficient. LONGi have paid particular attention to this and their panels are subject to reduced degradation.

Installed modules are normally expected to lose 2% efficiency in year one, and 0.45% per year after that for up to 30 years after the module was installed. At the end of their 30 year lifespan these panels would be expected to deliver 84.95% of their original rated power output. This is above the industry average, which is 80% output at 25 years.

LONGi Solar Panels Specifications

  • Cell Orientation: 108 (6×18)
  • Frame: Anodized aluminium alloy
  • Glass: 32mm coated tempered glass
  • Weight: 21.5kg
  • Dimensions: 1722x1134x30mm


Module Type LR5-54HIB-390M LR5-54HIB-395M LR5-54HIB-400M LR5-54HIB-405M LR5-54HIB-410M
Testing Condition STC STC STC STC STC
Maximum Power (Pmax/W) 390 395 400 405 410
Open Circuit Voltage (Voc/V) 36.5 36.65 36.8 36.95 37.1
Short Circuit Current (Isc/A) 13.35 13.55 13.66 13.74 13.84
Voltage at Maximum Power (Vmp/V) 30.8 30.95 31.1 31.25 31.4
Current at Maximum Power (Imp/A) 12.67 12.77 12.87 12.96 13.06
Module Efficiency (%) 20 20.2 20.5 20.7 21


LONGi Solar Panel FAQs

Q: How many solar panels would fit on a normal-size house roof?

A: Normally 6-10 KW arrays are used when installing solar panels on UK residences, but it depends on location and how much solar power is required to be generated. A solar installer will be able to advise on the right size of solar array.

 Q: Are LONGi solar panels reliable?

A: Most modern solar panels are extremely reliable. They are “solid state” so have virtually no moving parts that can break. However, they do degrade, due to what is know as light induced degradation, as the power output reduces over time. With regular solar panels maintenance should still deliver 25+ years of reliable service with minimal degradation each year.

LONGi have been at the forefront of developing in using gallium-doped silicon to reduce light induced degradation, and their use of smart soldering technology helps improve energy efficiencies, making LONGi solar panels a very good option for a new installation or to replace previous panels.

 Q: What warranty do LONGi offer with their solar panels?

A: LONGi offers 12 year warranty for materials and processing, which is fairly standard in the solar industry. LONGi also has an excellent 25 years performance warranty for the power output, making them a great solar PV system option for those looking for a bit more than just your affordable mid range panel.

 Q: Can you fit LONGi solar cells on flat roofs?

A: Like most solar panels, LONGi panel arrays can be deployed on a wide variety of different types of roofs, including flat roofs, though the right solar panels will need to be ascertained. The exact configuration and mounting needs of the solar system will also be determined by the installer.

LONGi Solar Panel Review Summary

LONGi Solar has become the largest of solar panel manufacturers in the world and is also concentrating resources into R&D to create cutting-edge, innovative solar cell technologies like PERC. Using its a massive production capacity, LONGi is not only generally driving down costs of silicon wafers and solar cells, but also producing highly-efficient, cost-effective solar panels for residential usage.

The panels are robust and represent the culmination of a great deal of research into monocrystalline wafers, which are the LONGi speciality, as well as half-cells, bifacial modules and PERC.

Overall, LONGi Hi-MO 5 solar panels are good value for money for those looking for affordable solar panels with an advanced specification from a solar company that is here to stay. While LONGi solar panels cost more than some other competitors, the prime benefit is reduced long-term degradation, which should increase lifespan and provide a better return on investment and impact on electricity bills more than many other solar panels.

Build Your Own Solar Quote

Build Your Solar Quote Today

Justine Effective
Read more articles...