Trina Solar has unveiled a new THBC solar technology that has already surpassed 28% efficiency on a commercial-size cell, opening a new chapter for crystalline silicon photovoltaics.
A new milestone for crystalline silicon solar cells
A new world record has been set in solar energy. On April 26, Trina Solar’s National Key Laboratory of Photovoltaic Science and Technology (PVST) unveiled an innovative photovoltaic device known as THBC, short for TOPCon-compatible Hybrid Back-contact Cell. The company announced that the technology has already exceeded the 28% conversion efficiency threshold on a large-area active cell.
In the race to develop the most efficient photovoltaic technology, THBC solar technology has quickly secured a strong position despite being a recent innovation. It is already emerging as a potential competitor to TOPCon solar cells, whose theoretical maximum efficiency stands at 28.7%.
To understand the significance of this achievement, it is worth looking at how the technology works.
What is THBC solar technology?
Unlike conventional TBC (TOPCon Back Contact) cells, which rely on TOPCon passivation created through high-temperature diffusion processes, THBC uses a hybrid passivation architecture.
Specifically, the design combines TOPCon’s high-temperature tunnel oxide layer with the amorphous silicon passivation technology used in HJT (heterojunction) solar cells. This approach delivers extremely low electrical resistance and very high open-circuit voltage.
As with both TBC and THBC configurations, all electrical contacts are positioned on the rear side of the cell through a back-contact (BC) design.
“The result is an efficiency of 28.00%, positioning THBC solar technology as the new benchmark for single-junction crystalline silicon cells,” the laboratory’s scientists stated.
The achievement was independently certified by the German Institute for Solar Energy Research Hamelin, ISFH.
The advantages of THBC solar technology
The record was achieved on a commercial-format 210R rectangular cell, typically measuring 210 mm by 182 mm. This format has been widely adopted by leading photovoltaic manufacturers because it enables modules to exceed the 600 W to 700 W power range more easily.
Achieving such a high efficiency level on a commercially relevant cell size, rather than on a small laboratory prototype, suggests that the innovation is already close to large-scale manufacturing.
Another major advantage is its compatibility with existing TOPCon production lines. This reduces industrialization barriers and could accelerate market deployment.
Based on its operational THBC pilot line, Trina Solar expects standard-sized modules measuring 2,382 mm by 1,134 mm to surpass 700 W of output power.
For rapidly growing solar markets across Africa, including countries such as Senegal, South Africa and Ethiopia, technologies that combine higher efficiency with compatibility with existing manufacturing infrastructure could help accelerate the deployment of utility-scale and distributed solar projects.
When will THBC solar cells reach the market?
“In the future era of crystalline silicon, Trina Solar will define a new paradigm based on the dual-engine strategy of TOPCon and THBC,” said Gao Jifan, Chairman of Trina Solar and Director of the laboratory.
According to the company, its roadmap will follow two parallel tracks. On one side, it will continue enhancing TOPCon technology through future 3.0 and 4.0 generations to maximize bifacial energy generation. On the other, it will accelerate the industrialization of THBC solar technology to capitalize on its superior front-side power output and create additional value for customers.
Trina Solar says the first commercial generation of THBC cells will be launched soon.
According to the laboratory, THBC overcomes the limitations of a single-technology approach by combining the strengths of TOPCon, HJT and back-contact architectures. Beyond surpassing the 28% efficiency barrier, the company believes the technology will deliver benefits across energy generation performance, industrial design and low-carbon sustainability in future photovoltaic products.
