First released May 2019
Updated October 2020
REC founded in Norway in 1996 has grown to become a leading innovator of solar PV technology with over 2000 employees and an advanced manufacturing plant in Singapore producing around 1.5 GW of solar panels per year. REC is growing rapidly with a total production volume increase of almost 40% in 2018, although this is still relatively small compared to the massive Chinese solar manufacturers. The company is also one of the industry leaders in sustainability through utilising many advanced, efficient manufacturing methods to reduce the energy payback time and emissions throughout the production process.
The operations headquarters and manufacturing facilities are located in Singapore while the new parent company is the China National Bluestar Group. REC is a fully vertically integrated company which means they produce everything from the silicon ingots, cell wafers and complete module assembly, thus the company has complete control over the quality and traceability of all components.
REC claims to have the lowest warranty rate in the industry which is a big call and hard to verify, although considering the largely positive feedback we have from Australian solar professionals, they are definitely known to produce highly reliable and great performing panels, especially in the harsh Australian climate with very few known quality issues.
REC Panel and Cell Technology
REC was the first company worldwide to release panels utilising the innovative split module design with half-cut cells, rather than the standard full size square cells. Due to the many advantages and improved efficiency of the half-cell design this clever innovation is now becoming an industry standard with many other manufacturers developing panels with half-cut cells. REC also incorporate the high efficiency PERC cell architecture in the full range of TwinPeak panels.
Innovation of half-cut cells
The half-cut cell and split module design effectively splits the panel into two halves with 60 ‘half-size’ cells in each section resulting in a total of 120 cells. The two halves are joined in parallel at the center of the panel but operate separately which means if one half is shaded it does not reduce the performance of the other half of the panel.
Traditional full size 60 cell panels can suffer up to 40% power loss when a small portion the panel is shaded. Another advantage of half-cut cell format is the current is reduced to half per side which in turn reduces resistance and losses by 75% and lowers the potential of hot spot formation from shaded cells. Further to this, due to the lower current the busbars are can be reduced in size meaning less cell shading and further efficiency improvements. All up the half-cut cell and split panel design results in higher efficiency and improved performance over the life of the panel.
High performance N-type silicon cells
The release of the N-Peak series in 2018 reinforced REC’s position as the leaders in half-cut cell technology. REC was the first manufacturer to develop a half-cut cells using high performance N-type silicon as opposed to the more common lower cost P-type mono or multi silicon wafers. This puts REC in a similar league to LG, Panasonic and SunPower who are the only other manufacturers to use the more advanced, high purity N-type silicon wafers, although as yet neither of these leading manufacturers have developed panels using half-cut cells.
In addition to the N-type silicon REC have included PERT or ‘passivated emitter rear totally diffused’ cell technology. The PERT process improves cell efficiency by using full passivation on the back side of the cell to absorb more light photons and generating more energy.
Heterojunction HJT cells
The new Alpha series from REC are the first mass produced panels featuring heterojunction (HJT) half-cut cells. The HJT cells are built on a high purity N-type silicon base with a thin-film layer of amorphous silicon above and below the cell. Together with 16 micro-wire busbars and advanced cell interconnections this significantly boosts efficiency and provides exceptional high temperature performance with a very low temperature co-efficient.
The REC Range of Panels
REC produce a range of panels for residential and commercial applications utilising half-cut PERC cells with various panel sizes and configurations available. The new Alpha series use the advanced HJT cells while the N-peak series use high grade N-type monocrystalline silicon cells for increased all round performance and reliability. The solar industry is moving towards more efficient cells but REC are ahead of the pack in developing HJT and N-type mono cells.
REC Alpha Series
REC group released the Alpha series panels in 2019 which use advanced heterojunction (HJT) cells in a half-cut panel format to deliver up to 380W. The next generation HJT cells also feature 16 micro-busbars to achieve an impressive 21.7% peak efficiency putting them in the same class as the industry leaders in solar panel efficiency SunPower and LG.
REC Alpha series solar panel key Features
High panel efficiency of 21.7% max at 380Wp
First multi-busbar cells with 16 micro wires.
First panels with heterojunction (HJT) half-cut cells.
Extremely good high temperature performance (-0.26%/degC)
High strength frame design with up to 7000Pa front load rating
See full specification sheet here - REC Alpha series solar panel
TwinPeak 2 Mono
The next evolution TwinPeak 2 range of panels increased power output up to 300W using more efficient multi PERC monocrystalline half-cut cells. Now with a standard 20 year product warranty and 25 year performance warranty.
At the mid to high end are the N-Peak panels with up to 330W power output. These were the first panels developed my REC using the high-grade N-type silicon cells utilising PERT architecture. Panels featuring the more expensive N-type cells generally come at a premium price being around 20% higher than common mono panels, but with the higher price comes higher performance and efficiency with lower degradation over the life of panel. The N-peak panels also feature a reinforced frame structure with extra support bracing across the rear of the panel, plus a longer 12 year product warranty and improved performance warranty with 86% retained capacity after 25 years.
Commercial and Utility Panels
REC offer the same half-cut split panel technology for commercial applications but in the common larger 72 cell format, plus standard 72 cell multicrystalline panels.
TwinPeak S2 Mono 72 - 370W to 390W - N-type Monocrystalline
Alpha 72 series - 430W to 450W - Monocrystalline N-type HJC
Performance and Reliability
REC panels have consistently scored well in the internationally recognised DNV-GL independent solar module testing program scoring as a ‘Top performer’ in all four durability tests. The DNV-GL test results rate the REC TwinPeak modules one of the ‘Top Performers’.
The high grade N-type silicon cells used in the new N-peak panels claim to drastically reduce LID or ‘light induced degradation’ which means they will out-perform all common panels using the standard P-type cells. All solar panels lose capacity over time, with the standard degradation rate of 0.7 to 0.8% per year resulting in around 80% output after 25 years. However, N-type silicon cells have a very low degradation rate of less than 0.5% per year. This means after 25 years the N-peak panels are warranted to still maintain 86% of the original rated output, while Alpha series featuring HJT N-type cells have an impressive 25 year product warrant with 92% retained power output after 25 years!
High strength frames
Possibly due to several frame issues in the past, REC engineered a new high strength frame design for the N-Peak and Alpha series panels with two additional cross members to reinforce the entire frame structure (and keep it square). This increases the panel maximum load bearing from 5400 Pa to 7000 Pa which is far above the industry standard and makes these some of the strongest panels available.
Warranty and service
From early 2019, REC began offering a 20 year manufacturer’s Product warranty (previously 10 year) together with the standard 25 performance warranty on all TwinPeak and N-peak panels. However, the REC solar installer certification program boosts the product warranty by an additional 5 years, for a total product warranty period of 25 years. Read more about the REC solar professional program here.
The new warranty was a big step up from the previous 10 year product warranty, but it’s not surprising considering REC’s good reputation and low failure rates. The N-peak panels will with come with a 20 year product warranty and 25 year performance warranty to 86% retained power output while the new Alpha series have an impressive 25 year product warrant with 92% retained power output after 25 years! With global support offices in the US, Germany, India, Japan, Singapore and a support office in Melbourne, REC have a quite good reputation and service in the event of a warranty issue or claim.
With a solid track record and low failure rates, the REC Twinpeak range of panels have been a reliable choice and a regular favorite among both customers and installers, especially when partial shading is an issue. The impressive new Alpha series has cemented REC’s place as an industry leader in PV cell technology and is helping fast track the development of next generation, high efficiency heterojunction cells. The 20 and 25 year product warranties and increased performance warranties puts REC ahead of most other manufacturers and highlight the long-life characteristics of premium N-type silicon cells.
With the out-of-square frame issue now in the past and the release of the new high-grade, extra-strength N-peak and Alpha series panels, REC has moved into the premium class of manufacturers. Premium panels do come at a premium price, but the relatively small additional cost for high performance panels brings much greater performance, reliability and increased generation over the life of the system.