PVT + Heat Pump: BTESolar PVT-E "Thermoelectric Twin System" Opens a New Era of Solar Energy Comprehensive Utilization

Driven by the global energy transition and the "dual carbon" goals, how to make use of the limited rooftop space to generate both electricity and heat has become an important issue in the field of new energy. As an innovative enterprise that has been deeply engaged in solar thermal utilization for over a decade, Texas-based BTE Solar Co., Ltd. (BTESolar) unveiled its latest PVT-E series of photovoltaic-thermal integrated products - the PVT-E "thermoelectric twin system" at the Intersolar Europe exhibition in 2025. This new product integrates photovoltaic power generation and solar thermal collection technologies, achieving "one panel, dual benefits", providing a new solution for the efficient coupling of the PVT + heat pump system. 

I. Product Introduction: A Leap from Photoelectricity to Photo-thermal Technology 

The core innovation of the BTESolar PVT-E series lies in its "thermoelectric twin" design concept. When traditional photovoltaic panels generate electricity, an increase in the temperature of the cell leads to a significant decline in power efficiency - for every 1℃ increase in the temperature of a crystalline silicon photovoltaic cell, the power efficiency drops by 0.4% to 0.5%. The PVT-E achieves this by integrating a heat collection system on the back of the photovoltaic panel, recovering and reusing this wasted heat energy, while also lowering the operating temperature of the cells, achieving a dual output of "electricity generation and heat production". 

In terms of technical parameters, the PVT-E series demonstrates outstanding performance. Taking the flagship model PVT580 as an example, the size of a single panel is 2279×1134×37 millimeters, with a weight of 39 kilograms. It uses 144 N-type TOPCon half-cell batteries and has a maximum power output of 580W, with a photovoltaic conversion efficiency of up to 22.44%. At the same time, its heat collection system adopts a copper tube plate heat exchange structure, with 1.2 liters of propylene glycol anti-freezing conductive liquid inside, and the peak heat power can reach 1180W. It can simultaneously produce hot water at around 60°C. This means that the energy output of a single PVT panel is equivalent to the total output of traditional photovoltaic panels and flat plate collectors, and the **solar energy comprehensive utilization rate** per unit area has significantly increased to over 80%. 

The PVT-E product adopts an indirect expansion design, with a working pressure of 0.6 MPa and a working temperature range covering -40°C to 85°C. It can adapt to various climatic conditions ranging from the cold northern regions to the hot southern regions. Its core structure includes tempered glass cover plate, EVA film, high-efficiency photovoltaic cells, heat-absorbing aluminum plate, copper tube heat exchange flow path, and TPT insulation layer, achieving precise coupling of photovoltaic conversion and heat collection. Compared with traditional photovoltaic systems, PVT-E can reduce the surface temperature of the components by 8-15°C, thereby increasing the power generation efficiency by 8%-15% and extending the service life of the components. 

II. Application Scenarios: Full Coverage from Residential Homes to Industrial Parks 

After the PVT-E "thermoelectric twin system" is deeply coupled with the heat pump, it can be widely applied in various scenarios and achieve "electricity - heat - cold" triple supply. 

1. Zero-carbon residences and high-end villas

For households that aim for energy self-sufficiency, the PVT-E system can be integrated with air-source heat pumps or water-source heat pumps to form a PVT + heat pump integrated energy system. The green electricity generated by the system can directly drive the heat pump compressor, while the thermal energy collected by the PVT components serves as the low-temperature heat source for the heat pump, significantly improving the energy efficiency ratio (COP) of the heat pump. According to calculations, after coupling with the heat pump, the annual performance coefficient (APF) of the PVT system can be improved by approximately 25% compared to traditional air-source heat pumps. A standard household system can meet the annual domestic hot water, winter floor heating, and most of the domestic electricity consumption needs, achieving "net zero energy consumption" at the household level. 

2. Public Buildings and Commercial Facilities

Buildings such as hotels, hospitals, and schools have a significant and continuous demand for hot water and heating. In a primary school project, 69 PVT panels were linked with the ground source heat pump system, replacing the original gas boiler. It is estimated that this can reduce nearly 80% of the carbon emissions related to heating. In large sports venues, university dormitories, and other scenarios, the PVT system is linked with the ground source heat pump to achieve integrated intelligent energy supply for power generation, heating, cooling, and energy storage throughout the year. The PVT project case of Zhengxin Optoelectronics shows that in an ink printing factory, 280 PVT components generate approximately 700 kWh of electricity on average per day, and produce about 40 tons of heat energy. This results in a 30% reduction in energy consumption for the enterprise throughout the year, with an investment payback period of only over three years. 

3. Agriculture and Facility Agriculture

Agricultural greenhouses are an important application scenario for PVT + heat pumps. During the day, PVT components absorb solar energy to generate electricity, while also collecting excess heat from the roof and storing it in water tanks or underground; at night, the heat pump uses the stored heat to provide heating for the greenhouse, maintaining the temperature for crop growth and solving the energy consumption problem of off-season planting. A compact heat pump system integrating PVT and heat storage tanks is being developed, which can increase the heating efficiency of domestic hot water by up to 30% using the PVT heat source. 

4. Industrial Heat Utilization and Seasonal Energy Storage

In the industrial sector, the PVT-E system can provide process heat preheating for industries such as dyeing and food processing. With the adoption of the PVT + heat pump system, the unit cost of hot water for dyeing factories is only 3.1 yuan per ton, which is much lower than 25.9 yuan per ton for municipal steam and 19.5 yuan per ton for natural gas. Additionally, the PVT system supports cross-seasonal heat storage applications, storing the surplus solar heat from summer in the underground borehole heat storage system (BTES) for use in winter heating. 

III. Development Trends: Intelligence, Standardization and Globalization 

The PVT + heat pump technology is currently in a crucial stage of transitioning from "minor innovation" to "large-scale application". According to industry predictions, the compound annual growth rate of the PVT niche market will reach 9.62% in the next 10 years. 

1. System Integration and Intelligence

The future PVT system is no longer a simple combination of photovoltaics and heat pumps; instead, it is an intelligent energy management platform based on AI. Xianxin Integration's latest dual-source heat pump product integrates air source and PVT heat sources, relying on intelligent algorithms to analyze the energy efficiency of the two sources in real time and automatically switch operating modes: when the sunlight is good, the PVT heat source is prioritized; on cloudy days and at night, it automatically switches to the air source heat pump mode, achieving "energy efficiency priority and stable backup". This dual-source intelligent collaborative technology represents the development direction of the PVT + heat pump system. At the same time, the system supports remote monitoring via WiFi/4G, cloud data management, and intelligent maintenance. 

2. Product Standardization and Building Integration

The PVT system's standardization development is being promoted, with efforts to identify innovation obstacles and strengthen cooperation between industries and research institutions. Through a six-site production layout and complete industrial chain integration, BTESolar is driving the development of PVT components towards a building materialization direction, making them capable of simultaneously performing power generation, heat collection, insulation, and waterproofing functions, achieving photovoltaic-thermal building integration (BIPVT). 

3. Efficient Matching of Medium-High Temperature Heat Pumps and PVT

With the development of new refrigerants (such as R290, CO₂) and dual-stage compression heat pump technology, PVT will be deeply coupled with medium-high temperature heat pumps. The L-Sol project at ZHAW in Switzerland is researching a heating system combining PVT with air-source heat pumps, optimizing the efficiency of the heat pump source side through the "cold storage tank" design. Research by Fraunhofer ISE shows that by ingeniously combining the heat dissipation and heat absorption components of the refrigeration circuit with the storage temperature level, an efficiency improvement of up to 10% can be achieved during heating operation. 

4. Integrated Generation, Load and Storage with Zero-Carbon Park

The PVT + heat pump system will serve as a crucial fulcrum for building the "source-network-load-storage" integration framework in the new power system. By leveraging the "thermal energy storage" feature of heat pumps, fluctuating photovoltaic power is converted into thermal energy for storage, enabling optimal energy allocation in terms of time and space. The combination of PVT with solar thermal energy, heat pumps, and thermal storage systems provides industrial process heat of up to 250°C for the food, chemical, and paper industries. 

Conclusion

The emergence of BTESolar PVT-E "thermoelectric twin system" has provided a high-performance and highly reliable Chinese solution for the field of photovoltaic and thermal integration. From a single panel to a complete system, from a single building to an entire park, the "photovoltaic-thermal synergy" technology path of PVT + heat pump is reshaping the fundamental logic of energy utilization. In the grand narrative of carbon neutrality, PVT + heat pump is not only a product innovation, but also represents a more efficient, more intensive, and more sustainable energy future. With the continuous iteration of technology and the continuous expansion of the market, BTESolar and its PVT-E system are expected to leave a significant mark in the global clean energy landscape.