FAQ
Find quick answers to the most common questions about our products, customization, orders, and services.
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HKWELL Installation Process
Your request concerns a project already in progress?
First, you should contact the installer you are in contact with.
Your request concerns general information on our SPRING or FLASH products?
Access our FAQ which answers most of the questions asked. We feed it continuously to be as relevant as possible.
For any other questions you can contact us via email: ran.liu@hkwsolar.com
Yes. It is obviously possible to contact an installer before the construction of your house to discuss and plan what is needed for the installation of HKWELL panels. For us to put you in contact with the installer however, we prefer that the scope of the installation be very clear and the building permit already written up. Before that it is better to discuss the project directly with the architect or your design office.
The general safety requirements for various electrical workers are as follows. For rooftop installers it is necessary:
In France for both SPRING and FLASH panels it is mandatory to be validated as a QualiPV instalator?
FLASH panels installation
For all people working on the roofs it is necessary :
to have previous experience setting up photovoltaic installations under similar conditions
to have a BP electrical clearance
to be aware of the dangers of grid-connected PV (electricity, wiring of modules)
to be trained for works-at-height
For electrical installers it is necessary:
to have previous experience setting up photovoltaic installations under similar conditions
to have electrical clearance for working on PV installations
to have received training in grid-connected PV, particularly in terms of protection of persons and property
to have a BR(P) electrical clearance
SPRING Panels installation
In addition to all the point needed for the FLASH panels it is necessary to validate experience in setting up hydraulic or thermic installation similar to HKWELL system.
HKWELL Advantages
In terms of thermal efficiency, HKWELL SPRING hybrid panels are different from conventional solar thermal panels.
The main difference lies in the front face of the panels.
A solely thermal solar panel consists of a double-glazed front panel, which makes it possible to create a greenhouse effect, while the HKWELL panel is covered with photovoltaic cells, therefore with single glazing.
The performance of thermal and hybrid solar panels is described by the following coefficients:
a0: The optical yield, which represents the percentage of incident solar radiation that will actually be absorbed by the solar collector. It characterizes the transparence and absorptive capacity of the collector. The close this value is to 1, the better the quality of the collector in this respect.
a1 (measured in W/K⋅m²): The first-order coefficient, representing the constant-percentage losses, due to conduction and convection essentially. The smaller this number is, the lower these losses are and the better the collector is in this respect.
a2 (measured in W/K²⋅m²): The second-order coefficient, which describes those losses which increase as a function of temperature, due to infrared radiation essentially. Again, the smaller this number is, the lower these losses are and the better the collector is in this respect.
The following table provides a comparison of these coefficients in a conventional solar thermal panel and a HKWELL SPRING panel:
| Solar thermal panel* | Insulated HKWELL SPRING panel |
a0 (%) | 75.4 | 47.2 |
a1 (W/K/m²) | 4.14 | 9.1 |
a2 (W/K²/m²) | 0.0114 | 0 |
*Sample coefficients for a commercially available solar thermal panel
We find that hybrid solar panels do not have the same performance as solar thermal panels.
This is normal and in fact intentional: the HKWELL SPRING panel was designed not to rise to very high temperatures so as not to negatively impact photovoltaic production. At the same time, this eliminates the risk of thermal overheating.
This way the stagnation temperature of a HKWELL panel never exceeds 80°C, while a conventional solar thermal panel can reach temperatures well above 100°C and consequently bring the heat transfer fluid to a boil.
By its very design, a HKWELL SPRING panel is therefore unable to reach hot water temperatures as high as a conventional thermal panel.
The normal operating temperatures of HKWELL hybrid SPRING panels are approximately:
Summer: 55-60°C
Spring/Autumn: 40-45°C
Winter: 30-35°C
Thus it is necessary to plan for a larger hybrid panel area to achieve a coverage of domestic hot water needs similar to that of a conventional solar thermal installation, around 1.5-2 times more area depending on the application.
However, a HKWELL installation, compared to side by side photovoltaic (PV) and thermal (TH) modules rated at the same power, will take up 30% less roof space.
HKWELL presents multiple advantages including rooftop space, efficiency, design and cost! First, HKWELL panels, due to their innovative and patented hybrid technology, perform much better than standard photovoltaic panels. Photovoltaic panels become less efficient as outdoor temperature rises.
Due to the HKWELL panel’s heat exchanger, water circulation on the backside of the panel cools the PV frontside of the panel, allowing to increase the PV efficiency of the panel, AND generate hot water at the same time! With HKWELL, 1+1=3 and you save 30% of rooftop space for the same installed power output as for two separate PV and thermal installations. Moreover, aesthetically, a HKWELL installation is composed of one type of black-black panel, and thus is more visually harmonious than two separate PV and thermal installations side-by-side.
Note that a HKWELL panel has the same visual appearance as a PV panel, so you can decide to complete a HKWELL installation with additional PV panels without changing the aesthetic look of your installation. Finally, the labor costs of a HKWELL installation will be lower than two separate installations because the installation is less complex and requires less maintenance.
Where two PV and thermal side-by-side installations will require 2 different types of mounting, a HKWELL hybrid installation will only require labor for 1 type of mounting system. These are the principal reasons why you choose HKWELL over two separate PV and thermal installations!