Published： March 28, 2026
Last Modified：August 5, 2026
A photovoltaic thermal (PVT) collector is a hybrid solar technology that produces both electricity and useful heat from the same solar surface.
Unlike conventional photovoltaic (PV) modules that only generate electricity, PVT collectors recover thermal energy from the rear side of the PV module while simultaneously improving electrical performance through solar cell cooling.
By combining photovoltaic generation and solar thermal collection, PVT technology allows buildings and energy systems to obtain more useful energy from limited roof or ground area.
A photovoltaic thermal (PVT) collector, also called a hybrid solar collector or PV/T collector, is a solar device that generates both electrical and thermal energy from solar radiation.
A conventional PV module converts part of incoming sunlight into electricity. The remaining solar energy becomes heat, increasing the temperature of the PV cells and reducing electrical efficiency.
A PVT collector adds a thermal recovery system behind the photovoltaic module. This heat exchanger transfers thermal energy from the PV module to a heat transfer medium such as:
The result is a combined solar system:
Solar Radiation
↓
PVT Collector
↓
┌───────────────┐
│ Electricity │
│ from PV cells │
└───────────────┘
+
┌───────────────┐
│ Useful Heat │
│ recovery │
└───────────────┘According to the IEA SHC Task 60 overview, PVT collectors convert solar radiation into both usable thermal energy and electrical energy by combining PV cells with a solar thermal collector.
The front side of a PVT collector works similarly to a conventional photovoltaic module.
Solar cells convert part of the sunlight spectrum into electricity.
However, PV conversion is not perfect.
A large portion of solar radiation is converted into heat.
The IEA analysis of solar spectrum utilization illustrates that:
The rear thermal collector extracts heat from the PV module.
Typical components include:
For uncovered PVT collectors, the basic structure generally consists of the PV module combined with a rear heat exchanger. The thermal connection between PV cells and heat exchanger is critical because efficient heat transfer directly affects system performance.
PV cell efficiency decreases as cell temperature increases.
During strong solar irradiation, conventional PV modules can become significantly hotter than ambient conditions.
By removing heat from the rear side:
Therefore, PVT does not simply add a thermal collector behind PV.
It creates a combined energy system where thermal management improves total solar utilization.
Traditional solar technologies usually separate electricity and heat:
| Technology | Electricity | Heat |
|---|---|---|
| PV module | ✓ | ✕ |
| Solar thermal collector | ✕ | ✓ |
| PVT collector | ✓ | ✓ |
The main advantage of PVT is improved utilization of available solar area.
For buildings with limited roof space, a single PVT installation can provide:
The IEA SHC Task 60 report identifies applications including heat pump sources, domestic hot water, space heating, cooling, industrial process heat, and other solar thermal applications.
A common misunderstanding is that all PVT collectors work the same way.
In reality, PVT is a technology family.
The appropriate collector depends mainly on:
The IEA SHC Task 60 classification separates PVT collectors into different technology categories, including uncovered PVT, covered PVT, evacuated concepts, and concentrating PVT.
PVT technology has developed into several different collector concepts. The main differences are related to:
There is no universally “best” PVT collector. The optimal solution depends on the required thermal output and system application.
The IEA SHC Task 60 framework classifies PVT collectors according to different design approaches, including uncovered PVT, covered PVT, concentrating PVT, and other advanced concepts.
Uncovered PVT collectors are the simplest and most widely developed PVT concept.
They consist of:
Unlike glazed solar thermal collectors, uncovered PVT collectors do not use an additional transparent cover layer.
Because the collector is directly exposed to ambient conditions:
Advantages:
Limitations:
Uncovered PVT collectors are commonly considered for:
The IEA SHC Task 60 analysis identifies uncovered PVT collectors as particularly relevant for applications requiring low-temperature heat, including heat pump integration.
Covered PVT collectors add a transparent cover layer above the PV module.
The purpose is similar to conventional glazed solar thermal collectors:
Covered PVT collectors can provide:
The additional thermal insulation can increase PV module temperature.
Since PV efficiency decreases with increasing cell temperature, collector design must balance:
thermal gain
versus
electrical performance.
Covered PVT collectors are more suitable where:
Air PVT collectors use air as the heat transfer medium.
Instead of circulating liquid through channels, airflow removes heat from the rear of the PV module.
Air PVT systems can provide:
Air has lower heat capacity compared with liquids.
Therefore:
Air PVT is typically considered for:
Liquid PVT collectors use a liquid heat transfer medium.
Common fluids include:
Liquid systems are widely used because liquids have high heat capacity and can transport thermal energy efficiently.
Liquid PVT provides:
Typical applications include:
Brine PVT uses a water-antifreeze mixture as the heat transfer medium.
The collector transfers low-temperature solar heat into a brine loop, which can act as a heat source for a heat pump system.
The main reason is system reliability.
Compared with pure water systems, brine solutions provide improved protection against freezing conditions.
Solar Radiation
↓
Brine PVT Collector
↓
Low-temperature heat source
↓
Heat Pump
↓
Heating / Hot WaterBrine PVT is particularly relevant when:
Direct expansion PVT systems integrate the collector directly into a refrigeration cycle.
The refrigerant evaporates inside the collector, absorbing solar thermal energy.
DX PVT Collector
↓
Refrigerant Evaporation
↓
Heat Pump Compressor
↓
Heating OutputDX systems can achieve efficient heat transfer because:
DX PVT requires careful engineering regarding:
Concentrating PVT systems use optical components to increase solar concentration.
Examples include:
The objective is to increase the energy density received by PV cells and thermal absorbers.
Concentrating PVT is mainly considered for:
One of the most important principles when selecting a PVT collector is:
The required operating temperature determines the appropriate PVT technology.
Different applications require different temperature levels.
Typical temperature range:
approximately below conventional heating supply temperatures.
Suitable technologies:
Applications:
Suitable technologies:
Applications:
May require:
Applications:
A common mistake is asking:
“Which PVT collector is the best?”
The better engineering question is:
“What temperature level does my system require?”
The same collector may perform very differently depending on:
The IEA SHC Task 60 work emphasizes matching PVT collector concepts with appropriate applications and temperature requirements rather than treating PVT as one universal technology.
A PV module converts sunlight into electricity.
The unused solar energy mainly becomes heat.
A PVT collector converts solar radiation into:
| Feature | PV | PVT |
|---|---|---|
| Electricity generation | Yes | Yes |
| Heat recovery | No | Yes |
| Solar area utilization | Lower | Higher |
| Heat pump integration | Limited | Strong potential |
| System complexity | Lower | Higher |
| Energy output types | Electricity only | Electricity + Heat |
The advantage of PVT is not simply higher electrical output.
Its value comes from combining:
For buildings requiring both electricity and heat, PVT can increase the total useful energy obtained from the available solar surface.
A photovoltaic thermal (PVT) collector combines two renewable energy technologies into one integrated system.
However, PVT is not simply “PV plus solar thermal”.
Its value depends on whether the recovered thermal energy matches the actual energy demand of the project.
A well-designed PVT system can improve total solar energy utilization, but incorrect system selection may reduce the expected benefits.
The primary advantage of PVT is that the same collector area can provide:
Compared with separate PV and solar thermal installations, PVT can achieve higher utilization of available roof or ground area.
This is particularly valuable when:
A conventional PV system provides electricity only.
A conventional solar thermal system provides heat only.
PVT provides both:
| System | Electricity | Heat |
|---|---|---|
| PV | ✓ | ✕ |
| Solar Thermal | ✕ | ✓ |
| PVT | ✓ | ✓ |
For buildings with simultaneous electricity and heat demand, PVT can provide a more integrated renewable energy solution.
PV module efficiency decreases as cell temperature increases.
The thermal component of a PVT collector removes heat from the PV module, helping reduce operating temperature.
The recovered heat is not only a by-product.
It becomes a useful energy output.
This creates a dual benefit:
One of the important applications of PVT is acting as a renewable heat source for heat pump systems.
The IEA SHC Task 60 work identifies heat pump integration as one of the important application areas for PVT technology.
Compared with conventional heat sources, PVT can provide:
A traditional building energy system may require:
PVT integrates electrical and thermal generation into one collector.
Potential benefits:
Although PVT has significant potential, it also has engineering challenges.
Understanding limitations is essential for correct system design.
A PV system is relatively simple:
PV module
↓
Inverter
↓
Electrical load
A PVT system adds:
Therefore, PVT requires closer coordination between:
Electricity from PV can usually be consumed, stored, or exported.
Thermal energy requires a suitable heat demand.
For example:
A PVT system may produce heat during sunny periods.
If the building does not need heat at that time, thermal utilization becomes more challenging.
Therefore, system design should consider:
Higher thermal output often requires higher collector temperature.
However:
higher PV temperature
↓
lower electrical efficiency
Therefore, PVT design involves balancing:
The optimum operating point depends on the system objective.
PVT is most valuable when both electricity and heat are useful.
For example:
A building requiring only electricity may obtain limited additional value from thermal recovery.
A building requiring:
may benefit significantly more.
A common mistake is selecting a PVT collector first and trying to adapt the system afterward.
A better approach:
Energy Demand
↓
Required Temperature
↓
System Architecture
↓
PVT Collector SelectionThe collector type should follow the application requirement.
PVT technology can be applied in various sectors where electricity and thermal energy are both valuable.
Residential applications include:
Typical residential advantages:
Examples:
Commercial buildings often have:
PVT can help integrate renewable electricity and thermal energy.
Hotels are attractive applications because they often require:
Potential uses include:
Swimming pool heating is a common low-temperature solar thermal application.
PVT can provide:
Because pool heating generally operates at relatively low temperatures, it can match certain PVT concepts.
PVT and heat pumps are one of the most important application combinations.
A typical system:
PVT Collector
↓
Thermal Energy
↓
Heat Pump
↓
Heating / Hot WaterAdvantages:
Some industrial processes require low or medium-temperature heat.
Potential applications include:
The suitability depends on:
Selecting a PVT collector should follow an engineering process.
Ask:
What is the primary purpose?
Focus on:
Focus on:
Focus on:
Temperature is one of the most important selection criteria.
Examples:
| Application | Typical Requirement |
|---|---|
| Heat pump source | Low temperature heat |
| Domestic hot water | Medium temperature |
| Industrial heat | Higher temperature |
General guidance:
| Requirement | Suitable Concept |
|---|---|
| Heat pump source | Liquid / Brine PVT |
| Higher temperature | Covered PVT |
| Ventilation heating | Air PVT |
| Refrigerant integration | DX PVT |
Consider:
A collector suitable for a warm climate may not perform the same way in a cold climate.
The collector is only one part of the system.
Important elements include:
✓ You need both electricity and heat.
✓ Roof or land area is limited.
✓ A heat pump system requires a renewable heat source.
✓ Maximizing solar energy utilization is important.
✓ Electricity is the only objective.
✓ No useful thermal demand exists.
✓ Heat production is the only requirement.
This article is based on:
For Solis PVT system evaluation, technical decisions should be based on:
PVT stands for Photovoltaic Thermal.
It describes a hybrid solar collector that produces both electricity and thermal energy.
Not always.
PVT provides additional thermal energy, but the benefit depends on whether the recovered heat can be effectively used.
PVT can replace conventional PV in applications where both electricity and heat are required.
However, the best choice depends on the energy demand of the project.
Yes.
PVT is commonly considered as a renewable heat source for heat pump systems.
Yes, but the system design must consider:
Brine PVT transfers heat through a brine loop connected to the system.
DX PVT integrates directly with the refrigerant cycle.
The selection depends on system architecture and engineering requirements.
Recommended internal links:
Choosing the right PVT technology depends on:
Contact Solis PVT for technical discussion, application evaluation, and system selection support.