Heterojunction (HJT) Technology in Solar Panels

26 September 2023 by
Heterojunction (HJT) Technology in Solar Panels
AC Solar Warehouse Pty Ltd, Rob Birchall

Exploring the Advantages of Heterojunction (HJT) Technology in Solar Panels

Over the last 6 months there has been a lot of discussion about the benefits of solar module manufacturers moving from P-type to N-type cell technology. And we field a lot of questions from installers about how Heterojunction (HJT) technology fits into the picture.

Here’s a quick answer to that question focusing on three key factors:

Technology, Manufacturing, and Performance.

Technology

Both HJT and N-Type panels rely on a three-layer system called “wafers”.  This wafer system is designed to capture more light as the sun passes through each layer, compared to traditional solar cells which may see some light pass through the cell completely. This innovative setup ensures efficient light absorption, resulting in higher energy production.

What sets HJT apart is its use of a thin film on these three layers, further enhancing light absorption, and achieving remarkable efficiency up to 24%.

Manufacturing

It is relatively easy to convert existing traditional P-type cell production lines to make standard N-type cells, but manufacturing HJT cells is a very different process that requires substantial investment in whole new manufacturing equipment and processes.

Some manufacturers like  REC  have made the leap, investing in this new technology.  A simplified six-step manufacturing process (compared to the traditional fourteen with N-Type process) has gradually brought down the cost of HJT panels, making them increasingly competitive.  The shorter more efficient manufacturing process has seen considerable energy and cost savings in ‌HJT panel production providing significant environmental benefits.

Performance

The standout features of HJT panels is their high efficiency and low-temperature coefficient, both made possible by the additional thin film layers.  HJT panels recently received recognition for achieving the highest sunlight conversion efficiency of any cell technology, reaching an impressive 24.3% efficiency.It is now possible to purchase REC’s leading HJT panel, the  Alpha Pure-R  at a price comparable to mid-range options and even lower than some N-Type panels.
REC has just unveiled an extensive guide dedicated to the art of mastering Heterojunction Technology, building upon the key insights mentioned above while delving even deeper into the technical details.
Within this resource, REC elaborates on their Alpha HJT products’ remarkable guarantee of 92% power output at the 25-year mark, surpassing competitors with an impressively low degradation. Additionally, they introduce their groundbreaking REC Alpha Pure-R Series, setting a new global benchmark for residential solar panel installations, achieved through the utilisation of cutting-edge G12 HJT cells.

The REC 420W Alpha Pure-R solar panels are arriving soon with HJT technology, providing even more power.