PVT Panels can be extremely effective in increasing the Seasonal Performance Factor of Ground Source or Air Source Heat Pumps. The solar thermal element of the PVT panels can be used to provide hot water for the Hot Water Cylinder, and then once there is no further gain to be had the supply can be switched to increase the temperature of the buffer tank. Finally any further heat can be dumped into the ground to help recharge the earth temperature around the ground collectors. All of the above contribute to improving the SPF of the heat pump.
In addition to increasing the SPF of Heat Pumps, the PV Element of the PVT Panels qualifies for the Photovoltaic Feed-In Tariff and the Solar Thermal Side qualifies for the RHI as per the table below.
What is a PVT collector?
A PVT collector is the combined assembly of a PV module, for the conversion of electrical energy, with a high efficiency flat-plate solar collector, to convert thermal energy.
Photovoltaics (PV) are semiconductors, and a significant drawback – degradation in performance due to temperature. In the UK, on a sunny summer day, when one would expect maximum PV performance, the output will be significantly reduced because of the temperature of the silicon wafer in the PV.
By regulating panel temperature using a fluid cooling system, a balance can be produced, trading off between PV efficiency and thermal output. Using this principle, it is possible to obtain a higher electrical yield, coupled with enough free heat to offset a large proportion of the annual hot water requirements of a typical house.
Our Hybrid PVT Panels are a step-change technology which maximises the energy return from a given area. A finely balanced solution which optimises efficiency and saves space and money relative to alternative solar systems.
What are the benefits of PVT?
PVT is a hybrid technology which combines monocrystalline photovoltaics and a high efficiency solar thermal collector. There are multiple benefits:
A simple low cost, low maintenance energy solution capable of facilitating the government’s zero-carbon strategy.
Higher output efficiency at lower temperatures than the equivalent monocrystalline PV.
Space saving, only one panel is required to produce both heat and electricity.
Greatly improved paybacks over the combination of traditional PV and Solar Thermal technologies.
Provides opportunities in combination with other renewable technologies to most residential and light commercial buildings to reach zero-carbon.
What can be achieved with a PVT collector?
PVT collectors allow you to set-up a total solar energy system for both electrical and thermal energy generation because of its cooling effect on the PV module, this system has a higher efficiency at a much lower cost when compared to separate systems.
PV Performance/Operation Temp
All photovoltaics are tested under standard test conditions: at an irradiance level of 1000W/m2 and a temperature of 24°C.
PV performance and temperature are inextricably linked. For every 1°C rise temperature there is a drop of 0.5% of electrical output.
When under direct sunlight, the temperature of a standard PV module may be as high as 110°C, resulting in a 43% loss in efficiency due to heat, leading to a subsequent reduction in annual performance.
Increasing the Ground Temperature using PVT Panels
Ground Temperatures recorded at weekly intervals from August 2009 to November 2012. For three successive seasons, the summer high has been nearly 14Deg C. For three successive winters, the winter low was still above 10Deg C, compared to when there was no solar charging the winter low was 5 Deg C. The line and arrow indicates whe date of installation of the solar augmentation system.
The benefits of cooling a PV module
When the PV module is actively cooled, reducing its nominal temperature closer to that of standard test conditions, the overall annual output of the module will be improved. A Hybrid PVT panel, stabilised at an average of 45°C, will produce roughly 20% more output over a 12 month period (when compared to a PV system with the same peak output).
Life Expectancy and Warranty?
Our PVT collectors come with a 10 year manufacturer’s warranty, and a guaranteed output of at least 80% after 20 years.