What would you like to know more about?

Buying a roof is a big decision. It raises several questions.
We have collected the frequently asked questions – and our answers below.

Aesthetics

Does the Ennogie roof fit all house types?

In principle, yes; though some house types might cause structural challenges due to a complicated roof layout.

The Ennogie roof has obtained numerous awards for its beautiful layout. It is all up to you to decide if it matches your house, of course.

Is the Ennogie roof available in different shapes and colours?

The solar module itself is only available in black. The steel riders on the back of the module are usually black. We can also deliver them in another colour at an additional price.

However, this extends the delivery time.

What does it mean that the Ennogie roof is clinker-built?

The modules overlap in both directions: Length and width. This means that the lower edge of a module overlaps the module beneath it. This makes the Ennogie roof completely tight and it also makes a nice and simple layout.

Will the blank surface cause trouble with reflections from the sun?

Sunshine reflections from an Innogie roof cannot be measured the same way as reflections from ordinary roof types, e.g. glazed tiles. The visual impression reminds more about reflections from a roof light window or from a skylight. Therefore, most sunrays will not be reflected, but used inside the roof module itself in order to generate electricity. The exact degree of reflection also depends on the angle and slope of the Ennogie roof.

In special cases we will be able to calculate the reflection from your Ennogie roof before you make your decision.

Economy

How much money can I save monthly with an Ennogie roof?

Your savings depend on several factors; among others, the size of your roof and hence your own energy output (the self-supply rate), your energy consumption, and how the house is heated.

To newly built, low-energy houses, an Ennogie roof will provide sufficient energy for most of the year. An annual self-supply rate of more than 80 % is thus a whole new, profitable opportunity in Denmark.

Additionally, there is an indirect cost savings as the value of your house increases. Even with the Danish subvention-based financing, an Ennogie roof provides a return on investment of more than 10 %.

Please contact us so we can perform a non-committal calculation of your roof.

When will I start saving money with an Ennogie roof?

At the very moment, when the roof has been mounted and connected to your electrical switchboard, because your energy output starts immediately and with it your savings compared to the power purchased from your power supply company.

This is completely unique for an Ennogie roof: It pays back itself after some years, which does not apply to an ordinary roof.

What is the price of one Ennogie roof module?

The price for a complete roof – and thereby also for one single module – depends on several matters such as the roof condition, design and how much electricity you want to produce.

What does it cost to repair an Ennogie roof?

The price depends on the individual case. In case a module breaks, it can be exchanged without covering the other modules – and without disconnecting the system.

The repair usually only takes 15–20 minutes and is therefore inexpensive. As opposed to other solar systems, a broken module will only affect the system output slightly, and the system continues to produce electricity, even while the broken module is being exchanged.

We offer a service agreement including system surveillance and exchanging broken components.

Should I use professional workmen to install an Ennogie roof?

Usually your own workman who mounts the underlay, battens, gutter etc., will install the roof.

Installing an Ennogie roof has more in common with ordinary roof materials than with solar cell modules.
The modules overlap both by length and width whereby they provide a tight thermal envelope. The Ennogie roof is mounted to the construction beneath simply with self-tapping screws.

You can find mounting principles for roofs with fixed underlay and roofing underlay in the documentation section. Your electrician will connect the system to the electrical switchboard.

Operations and maintenance questions

How do I make surveillance on the Ennogie roof?

When the roof is mounted the Android and iOS app enables you to follow the energy output.

How do I clean an Ennogie roof?

The roof’s construction makes it difficult for debris to stick to the surface. Usually, a rain shower now and then will keep the roof clean. Pollen from surrounding trees and other factors can make it advantageous to clean the roof sometimes.

This service is typically performed by professional window cleaners or roof cleaners.

What happens if one of the roof modules breaks?

If a solar cell module should break, there is no danger. The solar cell modules consist of two pieces of glass that are held together with a flexible film in the centre – exactly as you know it from the windscreen of a car. Therefore, even if the glass is broken, the pieces are held together by the film. Due to the clever construction of the Ennogie roof it is possible to exchange a module without covering the other modules – and without disconnecting the system. As opposed to other solar cell systems, a broken module will only affect the system output slightly, and the system continues to produce electricity, even while the broken module is being exchanged.

What happens if an inverter is broken?

If an inverter breaks, it will automatically be reported to Ennogie. As soon as we have been notified about the problem, we will coordinate with you when and how to replace the inverter. In a typical system, a broken inverter causes less than 5 % power loss. We offer a service agreement including system surveillance and exchanging broken components.

Is there a warranty for an Ennogie roof?

Yes. We provide a product warranty of 10 years.

The product warranty includes solar cell modules, inverter and steel profiles, i.e. delamination of solar cell/adapter modules, failure in fastening between solar cell/adapter modules to steel riders, corrosion of steel riders/covers and broken inverters. The warranty is valid only, if the mounting has been performed by proper craftsmanship, and the contractor’s instructions for mounting and maintenance have been followed. Additionally, we provide a system output warranty for the solar cell modules, so that we are obliged to assure that system output is never lower than 90 % of the original performance after 10 years, and 80 % after 25 years.

Who can maintain my Ennogie roof?

The Ennogie roof does not require a lot of maintenance, because its construction includes a self-cleaning effect so that rain in most cases will do the job.

See also the entry “How do I clean an Ennogie roof?”. The roof’s properties of electricity production are not affected by a thin layer of dust or pollen on the surface.

Can I monitor my Ennogie roof when I am not at home?

Yes. You can monitor the energy output of the roof at any time on the app that comes with the roof, when it has been mounted. It only requires an internet connection.

Climate and environment

How much CO2 can be saved by an Ennogie roof?

In Denmark, a roof that produces 10,000 kWh can save approx. 2,000 kg CO2. If you expect the energy output to replace coal, approx. 5,000 kg CO2 will be saved.

How much CO2 does it cost to produce an Ennogie roof?

Usually, it takes one year to save the same amount of CO2 that was used to produce the Ennogie roof.

Is electricity from an Ennogie roof as clean as e.g. wind turbine electricity supplied from utilities?

As opposed to wind turbine power, the electricity from the Ennogie roof is produced where it is being used. The Ennogie is a roof and a power plant at the same time, therefore you also save the energy that would have been spent by producing an ordinary roof. Besides, the Ennogie roof does not occupy any ground surface as opposed to wind turbines and solar parks.

Technique

How do you transform light into electricity?

Sunlight consists of photons. When they hit the solar cell, a current of electrons is created which generates the electricity.

How much electricity can the Ennogie roof produce?

The energy output depends on several matters, e.g. the slope and orientation of the roof. As a rule of thumb, the roof produces roughly 70–100 Watt per square metre and 60–90 kWh per square metre per year.

Please contact us so we can perform a non-committal calculation of your roof.

Does the Ennogie roof work on overcast days?

Indeed, and in cloudy weather it really makes sense to make use of the whole surface. It is simply a matter of having as many square metres on the roof as possible.

With an Ennogie roof, an ordinary household will be self-sufficient with energy on a rainy day.

Does the Ennogie roof work at night?

At night, the Ennogie roof primarily works as an ordinary roof, because the current is generated by light, i.e. daylight.

However, if you use a battery pack, the electricity produced during daytime can be used at night. Therefore, this solution contributes to increase the electricity generated by yourself and makes you need less power from the utility.

What type of panel does Ennogie use?

Good aesthetics

In our opinion, panels of thin film have more advantages than the more traditional crystalline-silicon solar panels.
When it comes to the layout, the thin-film panels have no visible, square silicon washers and no marked tracks of soldering. Additionally, on our thin-film panels you will not find any heavy, encircling aluminium frames. Instead, they have a uniform black surface without any disturbing parts.

Robuste

The thin-film panels are more robust than the conventional, crystalline-silicon solar panels.
The silicon washers in the conventional, crystalline-silicon solar panels are normally very brittle and they break easily if the panel is loaded inappropriately. The phenomenon is known as micro cracking, and in best cases, the panel’s output is just decreased. In worst cases, a so-called “hot spot” occurs which can reduce the panel’s lifetime drastically. Micro cracking (small cracks in the washer) may also evolve during a period of time as a result of temperature variations between day and night and between summer and winter. The silicon washers do not expand to the same degree as the mounted soldering tracks, and this causes inappropriate tensions in the cell, and this shortens its lifetime.

High performance in high temperature

The efficiency of all solar cells drops at high temperatures. Temperature increase causes the output power from the panel to decrease. CdTe thin-film panels are, however, only half as sensitive to this phenomenon as crystalline-silicon solar cells.

More electricity per installed kWp

Though the power peak per square metre is lower in the case of thin-film panels than for crystalline-silicon solar panels, the yearly energy output per installed kWp is higher. (kWp = kilo Watt Peak = maximum energy output capacity per installed solar cell panel)
A comparison of the typical annual production by two 6 kW systems in Denmark will show that the crystalline-silicon solar panel system will produce 6,000 kWh, while the CdTe thin-film panels will produce 6,500 kWh – a difference of approx. 9 % (source: https://re.jrc.ec.europa.eu/). This has something to do with the fact that thin-film panels lose a smaller share of their nominal capacity both at high temperatures and in bad weather.

What is an inverter?

The inverter is a component that transforms the produced direct current (DC) to alternating current (AC). The Ennogie roof comes with so-called micro-inverters mounted on the roof, and not inside the house.

Why is the Ennogie roof installed with several small inverters instead of one big one?

There are many advantages by using the so-called micro-inverters:

High security during installation

By keeping the voltage below 60 V DC it is possible for the workmen to perform the electrical installation on the roof without requiring special security precautions. For instance, it is not dangerous to put connectors together and to take them apart.

High security during operation

The low voltage minimizes or eliminates the risk of electric arcs on the roof. This is particularly important in systems where the modules are integrated in the roof, and where the wires are placed directly on the roof battens.

High security for firefighters in case of fire

Whereas the voltage on the roof does not exceed 60 V DC there is no danger for electric shocks when extinguishing fire on the building.

Easy and safe module exchange

The low voltage enables the workman to exchange a module without having to cover the modules on the roof or having to shut down the system.

No “one-point-of-failure”

In a typical system, there are 24 micro-inverters. Should one of them fail, the remaining micro-inverters will keep producing electricity. A broken micro-inverter represents approx. 5 % power loss. At Ennogie, we will automatically be notified about the error, so that an exchange can be arranged.

Longer durability

The micro-inverters do not contain any electrolytic capacitors; this extends the lifetime substantially more than by use of string-inverters. The expected lifetime of the micro-inverters is more than 20 years. Most manufacturers of micro-inverters offer a guarantee of 20–25 years.

The inverters do not take up space indoors and they are silent

The inverters are installed in the roof, so they do not take up any space indoors. You only need to conduct one cable from the roof to the electrical switchboard. Additionally, there will be no ventilator noise from a string-inverter. Micro-inverters make no noise.

Works immediately

As opposed to string-inverters, micro-inverters do not need to be programmed. The energy production starts automatically two minutes after connecting the cables to the electrical switchboard.

How can I store the current produced by the Ennogie roof?

Several batteries on the market are able to store the electricity produced by your roof during daytime, so you can use the electricity at night time.

New batteries are launched on the market all the time. However, we recommend you to choose a battery for increasing the self-sufficiency level. Please contact us so we can perform a calculation of your house.

How big are the Ennogie roof modules?

Each module is 60 x 120 cm.

A roof’s dimensions are rarely an exact multiple of the module measurements. To fit the roof’s size, an adapter module can be used that is visually identical to the solar cell modules. It does not produce energy and it can be cut to the exact size at the construction site.

It is also used for chimneys, valley gutters, skylights etc. This grants a fully homogeneous expression.

How much does an Ennogie roof weigh?

The low weight of 18 kg per square metre classifies the roof as a light-weight roof, and therefore special precautions rarely need to be taken due to the weight of the roof. Here at Ennogie, we recommend a fixed underlay for roofs with a slope of less than 15 degrees; for slopes of more than 15 degrees, roofing underlay can be used. We recommend that an underlay is always used.

Can I mount an Ennogie roof myself?

Yes, basically you can – though it does require a workman’s background.
The modules overlap both by length and width thereby providing a tight thermal envelope. The Ennogie roof is mounted to the construction beneath simply with self-tapping screws.
You can find more information about mounting principles in our download section.

Does the Ennogie roof add special requirements to the roof construction?

No, basically the roof construction is identical to that of many other roofs.

At Ennogie, we recommend a fixed underlay for roofs with a slope of less than 15 degrees; for slopes of more than 15 degrees, roofing underlay can be used. We recommend that an underlay is always used.

The Ennogie roof can be used at slopes between 5 degrees and vertical.

CONTACT

Get started and get in touch with Ennogie

You are always welcome to contact us with questions about our products, our services, or anything else.

Tel.: +45 6915 3990 | Mail: info@ennogie.com