Building-Integrated Solar Collectors – Sole Maker of Blue & Black Films

In the field of building-integrated solar thermal utilization (BIST), the heat-absorbing film layer is regarded as the "soul component" of the collector - it directly determines the thermal conversion efficiency, system lifespan and overall economic performance. BTE Solar, leveraging its unique advantage of being the only company worldwide that simultaneously masters the core production technologies of both blue and black films, is adopting a "dual-film concurrent" strategic layout to provide high-performance, low-cost and all-scenario heat-absorbing film layer solutions for the global building-integrated solar collector plate market. 

I. Global uniqueness: Dual Blue & Black Film Lines – Sole Global, Proprietary

BTE Solar was founded in 2009 and its headquarters is located in "Solar City" of China - Dezhou, Shandong Province. The company has over 20 years of experience in the thermal engineering industry and is the only global supplier capable of simultaneously producing nano black chromium solar spectral highly selective absorption coatings (black films) and vacuum magnetron sputtering (PVD) solar spectral highly selective absorption coatings (blue films). This "dual-coating parallel" manufacturing capability makes BTE Solar stand out in the global solar thermal utilization industry. 

The blue film is produced using the vacuum magnetron sputtering roll-to-roll manufacturing process. Through the interference effect of multiple oxide layers, it presents a distinctive blue appearance. The black film employs the nano black chromium solar spectrum-selective absorption coating technology. In 2025, BTE Solar's magnetron sputtering roll-to-roll production line was officially put into operation, with an annual production capacity of 500万平方米 of nano black chromium solar selective absorption coatings and 2 million square meters of high-weather-resistant exterior heating panels. 

II. Core technical parameters: High absorption, low emission, extremely weather-resistant 

The blue film and the black film have distinct performance characteristics and are tailored to meet different market demands: 

1. Blue Coating: The solar absorption rate reaches 95% ± 2%, and the thermal emissivity is as low as 5% ± 2% (@80°C). It is the preferred choice for high-performance building-integrated collectors. Due to its outstanding optical properties, the blue coating dominates the high-end residential flat plate collector market in Europe and Asia. Approximately 55%-60% of the global selective coating market is for blue coating demand. 

2. Black Coating: The solar absorption rate reaches 94% ± 2%. The second-generation nano black chromium selective absorption coating, through formula upgrades, has an absorption rate exceeding 94%, with an emission rate lower than 8%. Its performance has improved by over 20% compared to the first-generation product. The black coating exhibits excellent performance in salt spray corrosion resistance, UV aging resistance, and thermal cycling stability. Additionally, the manufacturing cost is approximately 30% lower than that of the blue coating, providing significant competitive advantages in cost-sensitive markets such as Africa, South Asia, and Latin America. 

In terms of the base material, the heat absorption film layer of BTE Solar is based on aluminum or copper materials with a thickness of 0.3mm or 0.4mm. The width can be customized within the range of 750mm, 950mm, 1200mm, and 1250mm. The surface coating thickness of the film layer is only about 150 nanometers, but it meticulously constructs multi-layer structures such as bonding layers, blocking layers, and infrared reflection layers, achieving technical indicators with a solar energy absorption rate of over 95% and an extremely low thermal emissivity. 

III. Market Position: The two membranes together account for 60% of the global market share. 

With the dual-line layout of blue film and black film, BTE Solar's selective absorption coatings collectively account for approximately 60% of the global market share. The blue film, due to its high performance and compliance with international standards, is widely popular in developed regions and high-end applications; while the black film dominates the cost-sensitive market with its cost advantage. 

This market position is based on the company's profound technological accumulation. BTE Solar has established deep industry-university-research cooperation relationships with top research institutions such as the Institute of Semiconductors of the Chinese Academy of Sciences, Tsinghua University, and Shandong University. The company's products have obtained international authoritative certifications such as Solar Keymark, CE, and ISO 9001, and are exported to more than 40 countries and regions around the world. 

IV. Integrated Building Solar Thermal Utilization (BIST): Dual Membranes Enable Building Energy Efficiency 

In the field of integrated solar thermal utilization in buildings, the heat collection panels need to seamlessly blend with the building's facade and roof, and at the same time, they must meet strict requirements in terms of aesthetics and performance. The blue and black membrane heat-absorbing panels of BTE Solar are the core components for this application scenario. 

The blue-coated heat-absorbing panels, with their distinctive blue appearance and high-performance optical indicators, are suitable for high-end commercial buildings, zero-carbon residences, and public facilities that emphasize architectural aesthetics and energy efficiency. The black-coated heat-absorbing panels, with their excellent weather resistance and cost-effectiveness, are the ideal choice for large-scale building hot water projects such as large-scale public housing, schools, and hospitals. 

In practical applications, the heat absorption film layer of BTE Solar can be directly applied to the heat absorption plates of flat plate collectors (made of copper or aluminum), serving as the core heat capture component; it can also be used in the inner heat pipes or U-shaped tube heat absorption fins of vacuum tube collectors; and it can even be integrated into the building facade or roof to achieve the integration of architecture and energy. 

BTE Solar's modern intelligent factory is equipped with five specialized production lines, and the average efficiency of the entire production line is 55 seconds per piece. Guided by the concept of Industry 4.0, the company has established a digital closed-loop management system covering the entire process from raw material selection, precision processing to final product inspection. All products undergo strict testing before delivery and are provided with a 5-year warranty. 

V. Future Outlook: Continuously Leading Integrated Solar Heating Utilization in Construction 

With the rapid development of global green buildings and near-zero energy consumption buildings, the market for integrated solar thermal utilization in buildings is experiencing an unprecedented growth opportunity. As the only company in the world that simultaneously produces both blue and black films, BTE Solar will continue to deeply focus on the core technology of the heat-absorbing film layer. With the strategic advantage of dual film operation, it will provide more efficient, reliable, and economical core material solutions for the global building integrated solar collector plate market. 

From high-end residences in Europe to rural communities in Africa, from commercial complexes in Asia to large-scale public projects in Latin America, BTE Solar's blue and black heat-absorbing panels are leveraging the unique advantage of "dual membrane parallel operation" to empower the global green energy transformation of buildings. 

Regarding BTE Solar: BTE Solar was established in 2009 and its headquarters is located in Dezhou, Shandong Province, China. It is a technology-based enterprise specializing in the research, development, production and sales of solar thermal utilization systems and core materials. The company is the only global supplier capable of simultaneously producing nano black chromium solar spectrum highly selective absorption coatings (black films) and vacuum magnetron sputtering solar spectrum highly selective absorption coatings (blue films). Its products have obtained international certifications such as Solar Keymark, CE, and ISO 9001, and are exported to over 40 countries and regions worldwide. BTE Solar adheres to the development philosophy of "gratitude, integrity, learning, and innovation", and is committed to providing high-quality solar thermal utilization solutions for global customers.